Radio Propagation Reports

February 2012

2012-02-05T14:47:00.001Z

Propagation Summary
The current prediction for Sunspot Cycle 24 gives a smoothed sunspot number maximum of about 96 in February of 2013. We are currently about three years into Cycle 24. Increased activity in the last few months has raised the predicted maximum and moved it earlier in 2013. The current predicted size still makes this the smallest sunspot cycle in over 80 years.
The current prediction for Sunspot Cycle 24 gives a smoothed sunspot number maximum of about 96 in February of 2013. We are currently about three years into Cycle 24. Increased activity in the last few months has raised the predicted maximum and moved it earlier in 2013. The current predicted size still makes this the smallest sunspot cycle in over 80 years.

Forecast of Solar and Geomagnetic Activity 25 January - 20 February 2012 Solar activity is expected to be low with M-class flares likely until Regions 1401 and 1402 depart on 28 January. Predominantly quiet levels are expected for the remained of the period. Protons greater than 10 MeV remained above event threshold on 25 - 26 January. A return to background levels is expected for the remainder of the period. The greater than 2 MeV electron flux is expected to be at normal to moderate levels the entire period. The geomagnetic field is was at active to minor storm levels on 25 January as effects from the CME from 23 January waned. Quiet levels returned on 26 and 27 January as a coronal hole high speed stream (CHHSS) became geoeffecitve. A return to quiet levels is expected until 02 - 03 February, with quiet to unsettled levels expected as another CH HSS becomes geoeffective. Predominantly quiet levels are expected from 04-08 February. Another CH HSS is expected to become geoeffective with quiet to unsettled levels expected from 09-10 February. Predominantly quiet levels are expected for the remainder of the period.
http://www.swpc.noaa.gov/ftpdir/weekly/WKHF.txt

Sunspot 1402 produced a major X1.7 Solar Flare on 27 January at 18:37 UTC. An R3 Level Radio Blackout resulted, which led to the fading of HF signals on the sunlit side of Earth. The proton levels are on the rise again and the Moderate S2 level Radiation Storm threshold has been reached. A video of the solar flare is on line at:
http://www.youtube.com/watch?v=3uwojBpajIg&feature=player_embedded

Solar Conditions by Steve Nichols
Good solar conditions continue and we seem to have gone through quite a long period of settled geomagnetic conditions, which has helped no end. The solar flux index has hovered around the 130 mark with no really large fluctuations and as a result we are still seeing the higher bands come to life, notably 10m. But this is really the month for good low-band openings - 160m, 80m an 40m. Tony G3ZRJ reported hearing long delay echoes on 80m at about 2100z on 1st January 2012. These are either signals coming around the world "the wrong way", or aided by magnetospheric ducting, or some other form of propagation that we don't really understand. Whatever, it makes for some interesting effects. http://g0kya.blogspot.com
There is an article about Long Delay echoes (LDE’s) by radio ham Chris Codella at: http://www.w2pa.com/Home/articles/80m-echo-observations

Understanding LF and HF Propagation. (Free Ebook)
In 2008/2009, Alan Melia (G3NYK) and Steve Nichols (G0KYA) wrote a series of features on understanding LF and HF propagation for the RSGB "RadCom" magazine. The book can be downloaded in PDF format at: http://www.infotechcomms.co.uk/Understanding_LF_and_HF_propagation.pdf

Thanks to Mike Terry and Ken Fletcher for regular updates

January 2012

2012-01-12T01:07:00.004Z

Propagation Summary
The Solar Flux charts have shown a sharp increase in sunspot activity since mid November and by the end of November, average sunspot numbers have actually risen to 95 for the first time since 2003. This has even exceeded the predicted peak forecast for the first quarter of 2013. http://www.swpc.noaa.gov/SolarCycle/
Solar activity was at very low levels on 19 December and increased to low levels from 20–24 December, and finally ending the period (25 December) at moderate levels. Region 1376 was the most active group with frequent B– and C–class flare production until 25 December when new Region 1387 began producing multiple C–class flares and one M–class flare. On 22 December at 0208 UTC, Region 1381 produced a C5 flare associated with weak Types II and IV radio sweeps and a faint CME, determined to be non–geoeffective. Region 1386 produced a C5/Sf flare at 0839 UTC. Region 1376 produced a long–duration C4 flare on the west limb at 1236 UTC associated with a non–Earth–directed CME. On 25 December at 1816 UTC, Region 1387 produced an M4/1N flare that was accompanied by Type II and Type IV radio emissions. A slight proton enhancement was observed on 25 December and achieved a max flux of 3 pfu at 0135 UTC. More information can be found at: http://www.windows2universe.org/sun/solar_activity.html

Solar activity is expected to be at low to moderate levels until 31 December when Region 1387 is forecast to rotate off the disk. Activity is expected to return to low levels with a slight chance for isolated M–class activity for the remainder of the period. No proton events are expected at geosynchronous orbit. The greater than 2 MeV electron flux is expected to be at normal to moderate levels during the period. Geomagnetic field activity is expected to be at active levels from 28–29 December due to CME (Coronal Mass Ejection) arrivals. Diminishing effects from said CMEs will have brought geomagnetic field activity to unsettled levels by 30 December. Mostly quiet conditions were predicted for 31 December, 3–4 and 7–23 January. Activity is expected to be at predominately quiet to unsettled levels 1–2 and 5–6 January due to recurrent coronal hole high speed streams. Although radio blackout warnings have been issued at the end of December, reception conditions are predicted to be good during the quiet periods. ( http://www.swpc.noaa.gov/SolarCycle/ )

2012 Meteor Showers
The next major meteor shower will be the Quadrantid shower, which is expected to peak after midnight on the morning of January 4, 2012. This shower favours northerly latitudes in the Northern Hemisphere. If the peak happens as predicted – at 0700 to 0800 UTC, means eastern North America might be in a good position to watch the 2012 Quadrantid shower. Predicting the peak and the intensity of a meteor shower is always a tricky business, though. No matter where you live, the best time to watch is before dawn on January 4. Best months of the year for meteor scatter are August, October, November, December, and early January. Actually, anytime of the year is good. Sometimes certain dates are just better than others, due to the occurrence of meteor showers. Average peak daily time for night time showers: 0500 to 1200 local time (There are a handful of daytime showers that almost rival the big night time showers and the only way you can be aware of them is to do some research of when they occur.) Best frequencies for meteor scatter: 50MHz to 100 MHz. (The entire 88 to 108MHz band is usable for meteor scatter dxing.) General distance of reception is 600 – 1200 miles. Receiving satisfactory meteor skip signals depends on where you live, what type of equipment you are using, and availability to the peak times of the day ( http://earthsky.org/astronomy–essentials/earthskys–meteor–shower–guide ) Links to these articles can be found at http://www.jameswelsh.org.uk/ .
Thanks to Ken Fletcher and Mike Terry for regular updates during 2011

November 2011

2011-10-20T02:00:00.007+01:00

Propagation Summary
The Solar flux has peaked at 140 on September 27-28^th but there is again a downward trend, which will see a drop to 105 by November 7^th. The only noticeable disturbance on propagation conditions was on October 5-6, with the Boulder A index peaking at 18, and the K Index peaking at 5. The general trend for sunspot activity is up, although certainly not to the predicted levels. Daily updates can be found at http://www.wm7d.net/hamradio/solar/27d_forecast.shtml

Historical Solar charts going back to 1950 are available at http://www.solen.info/solar/history/

Implications for Long Term Space Climate Change

“The recent solar minimum was the longest and deepest of the space age, with the lowest average sunspot numbers for nearly a century. The Sun appears to be exiting a grand solar maximum (GSM) of activity which has persisted throughout the space age, and is headed into a significantly quieter period. Indeed, initial observations of solar cycle 24 (SC24) continue to show a relatively low heliospheric magnetic field strength and sunspot number (R), despite the average latitude of sunspots and the inclination of the heliospheric current sheet showing the rise to solar maximum is well underway. We extrapolate the available SC24 observations forward in time by assuming R will continue to follow a similar form to previous cycles, despite the end of the GSM, and predict a very weak cycle 24, with R peaking at ∼65–75 around the middle/end of 2012. Similarly, we estimate the heliospheric magnetic field strength will peak around 6nT. We estimate that average galactic cosmic ray fluxes above 1GV rigidity will be ∼10% higher in SC24 than SC23 and that the probability of a large SEP event during this cycle is 0.8, compared to 0.5 for SC23. Comparison of the SC24 R estimates with previous ends of GSMs inferred from 9300 years of cosmogenic isotope data places the current evolution of the Sun and heliosphere in the lowest 5% of cases, suggesting Maunder Minimum conditions are likely within the next 40 years.” From: http://www.agu.org/pubs/crossref/2011/2011GL049328.shtml

Solar Flare Alerts by Text or Phone

Real time solar activity alerts to your mobile phone or landline phone can be set up online at http://spaceweathertext.com (text) and http://spaceweatherphone.com (voice).

Future Sunspot Cycle Predictions

Sunspot Cycles are Difficult to Accurately Predict. Solar physicists believe the speed of a massive circulating current of hot plasma within the Sun predicts the amplitudes of sunspot Cycles approximately twenty years into the future. In the years prior to 2006 that speed had become lower than ever before. Based on the plasma-speed/future-cycle-amplitude theory, a team led by physicist Mausumi Dikpata of the National Centre for Atmospheric Research predicted Cycle 24 would be intense. NASA solar physicist David Hathaway agreed, but predicted Solar Cycle 25 will be very weak.

VHF Propagation Software

A new VHF propagation gadget is available from SV2AGW. There are two Windows Vista Side Bar gadgets, for Europe and North America. They display Aurora and Sporadic-e propagation using the dxrobot images. George Rossopoulos, SV2AGW has also produced software for AX.25 Packet / APRS, which can be downloaded from his website. http://www.sv2agw.com/downloads/default.htm (Via Mike Terry)

Thanks to Mike Terry and Ken Fletcher for regular updates. The next Propagation report will be in January. Links to these articles and more are available at http://www.jameswelsh.org.uk

September 2011

2011-08-22T15:04:00.003+01:00

Propagation Summary
August began with a peak in the Solar Flux of 130, which then dipped to 96 by August 14th. This pattern repeats roughly every 14 days. The next peak is estimated to be around September 6th , but the general trend is a downward one. The prediction charts on Solarcycle24.com show that, if the prediction charts are correct, Solar flux would need to reach 140 by the end of 2011, but during August they have actually dropped to the same levels as in January.

G0KYA's Amateur Radio Blog (Steve Nichols)
“We are moving away from the summer solstice, but we are a long way from the better autumnal HF conditions that we should start to see in mid September. The summer sporadic E season should also be diminishing. The last month or so has been characterised by big swings in the solar flux index and pretty poor conditions, although it doesn't pay to generalise. A chance glance at 17m a week or so ago showed a station from Los Angeles, calling CQ and with very few takers. He was about the only signal on the band! “ Steve’s blog and podcasts can be found at: http://g0kya.blogspot.com/

Sun storms 'could be more disruptive within decades' By Judith Burns. BBC News
Within decades, solar storms are likely to become more disruptive to planes and spacecraft, say researchers at Reading University. The work, published in Geophysical Research Letters, predicts that "In a grand solar maximum, the peaks of the 11-year sunspot cycle are larger and the average number of solar flares and associated events such as coronal mass ejections are greater. "On the other hand in a grand solar minimum there are almost no sunspots for several decades. The last time this happened was during the Maunder Minimum, between about 1650 and 1700." The research indicates that most radiation hits the Earth during periods of middling solar activity. Increased radiation is a particular problem for aviation and communications - technology that did not exist the last time the sun cycle ended its grand maximum.
http://www.bbc.co.uk/news/science-environment-14580995
Via Ken Fletcher

Space Weather Turns into an International Problem (NASA Science News)
Sometimes a problem is so big, one country cannot handle it alone.
That's the message scientists were delivering at July's International Living with a Star (ILWS) meeting in Bremen, Germany, and representatives from more than 25 of the world's most technologically-advanced nations gathered to hear what they had to say. "The problem is solar storms, and figuring out how to predict them and stay safe from their effects," says ILWS Chairperson Lika Guhathakurta of NASA headquarters. "We need to make progress on this before the next solar maximum arrives around 2013." While it probably will not be the biggest peak on record, human society has never been more vulnerable. The basics of daily life, from communications to weather forecasting to financial services—depend on satellites and high-tech electronics. http://science.nasa.gov/science-news/science-at-nasa/2010/16jul_ilws/

Spacecraft Sees Solar Storm Engulf Earth (August 18, 2011)
for the first time, a spacecraft far from Earth has turned and watched a solar storm engulf our planet. The movie, released during a NASA press conference, has galvanized solar physicists, who say it could lead to important advances in space weather forecasting.
“The movie sent chills down my spine,” says Craig DeForest of the Southwest Research Institute in Boulder, Colorado. "It shows a CME swelling into an enormous wall of plasma and then washing over the tiny blue speck of Earth where we live. I felt very small.” The video can be viewed at: http://science.nasa.gov/science-news/science-at-nasa/2011/18aug_cmemovie/

August 2011

2011-07-22T03:38:00.002+01:00

Propagation Summary
According to the forecast at http://www.swpc.noaa.gov/ftpdir/weekly/WKHF.txt solar activity is expected to be very low. However, there is a chance that new, rapidly emerging flux regions could increase activity to moderate levels at any time during the outlook period.
No proton events are expected at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit is expected to be at background or moderate levels for most of the outlook interval. However, increases to high levels are expected for 6-9 August in response to recurrent high speed streams.

Geomagnetic field activity was unsettled on 20-22 July due to a coronal hole. An increase to unsettled levels is expected on 27 July to 2 August due to another recurrent coronal hole. Quiet levels are expected for 3 August followed by another increase to unsettled levels for 04-10 August due to recurrence. 11-13 August is expected to be quiet and an increase to unsettled is expected for 14-15 August, again due to recurrence.
The Sunspot trend chart at http://www.solarham.com/sunspots.htm shows a sharp drop in sunspot activity which would suggest that the estimated peak forecast for the first quarter of 2013 will be well below the estimated number of 90.

Perseid Meteor Shower Peak August 12, 2011.
Good news for Meteor Shower DX’ers. The maximum of the Perseid activity in 2011 is expected during the night of the 12th August. The Perseids is the name of a prolific meteor shower. The shower is visible from mid-July each year, with the peak in activity being between August 9 and 14, depending on the particular location of the stream. During the peak, the rate of meteors reaches 60 or more per hour.
( http://earthsky.org/astronomy-essentials/earthskys-meteor-shower-guide )

Understanding Propagation
Here is a very useful article about Propagation modes. “Hop length is the ground distance covered by RF after it has been reflected once from the Ionosphere and returned to Earth. Maximum hop length is set by the height of the Ionosphere and curvature of the earth. The maximum hop length shown assumes antenna radiation of 4 degrees and the E and F layer heights as specified.” It is in PDF format and can be viewed, downloaded or printed from: http://www.hamqsl.com/Understanding%20Propagation.pdf

Space Weather Forecasting at the UK Met. Office
The UK Meteorological Office is developing a Space Weather forecasting system.
The key aims are to produce near real-time space weather ‘nowcasts’ and short-range forecasts by developing existing empirical analysis and modelling techniques as well as research with more sophisticated space weather models and to build an upgraded forecasting system. More details at: www.metoffice.gov.uk/

July 2011

2011-06-29T13:15:00.007+01:00

Propagation Summary
Sunspot numbers are continuing on a downward trend. June started with a Solar Flux of 115 and is forecast to peak roughly every 21 days. There was a peak forecast for June 26 at 105, and in July, there is a peak of just 100 forecast around the 14th. The dips in between could be as low as 85 on 7-10 July. The average daily Solar Flux reading for April was 112, dropping to 98.1 in May and averaging 98.5 in June (based on information available).
There has only been 1 spotless day in 2011 so far, compared with 51 spotless days in 2010 and 260 in 2009. The total number of spotless days since 2007 is 850.
Reception conditions are likely to remain the same during July with the Boulder A index averaging at 8.4 and the K index at 2.7. You can receive the latest accurate updates via email by subscribing to: http://www.spaceweather.com/

Europe to get space radiation-storm warning service
“International experts met in London in March, with the aim of setting up a European solar radiation-storm warning service. With the Sun expected to belch forth increasing amounts of bad "space weather" in coming years, the scientists warn that billions of pounds' worth of damage could be done to satellites in orbit.” (Lewis Page The Register: http://www.theregister.co.uk/2011/01/28/space_met_office/ . See also: http://www.bu.edu/cism/ )

Is a Dalton/Maunder Minimum possible?
Thomas F. Giella, writing in his blog recently has the following theory about the current solar conditions: “I personally believe we are headed for a "Dalton" type solar minimum but a "Maunder" type solar minimum is possible. As far as radio wave propagation is concerned, the higher HF bands would really be poor for decades, as the global climate is actually cooling not warming. Either a Dalton or Maunder solar minimum would be a global catastrophe where millions would starve and/or freeze to death and it would not be limited to the second or third world nations. (Thomas F Giella 15 June 2011 http://www.solarcycle24data.org/ )

About Sunspots
Sunspots are dark spots on the Sun caused by it’s magnetic field. The spots are dark because they are cooler than the area of the Sun that surrounds them and are often as big as the Earth.
The number of sunspots is controlled by the amount of distortion of the Sun's magnetic field. The magnetic field becomes distorted because the Sun's equator and core rotate more quickly than its other parts. As a result, sunspot activity varies over an average 11-year cycle. Over approximately 11 years, the Sun goes from a solar minimum (fewer spots) to a solar maximum (more spots) and back to a minimum again.
( http://www.bbc.co.uk/science/space/solarsystem/solar_system_highlights/solar_cycle )

Thanks to Ken Fletcher and Mike Terry for regular contributions

June 2011

2011-05-19T01:39:00.002+01:00

Propagation Summary
May began with sunspot numbers of 115 dropping to 110 for 5 days on the 6th, then by the end of May sunspot numbers had dropped to 105. The Boulder A and K indices have remained at their ‘norm’ of 5 and 2 during May, except for the 9th and 10th, with a peak of 15. May should finish with a rise to 15 once more.
Sunspot numbers in June should start at 105 but are likely to drop to as low as 92 by Jun 13. The A and K indices should peak at 12 and 4 by June 11th.
According to the trend charts at: http://www.solarham.com/sunspots.htm the predicted sunspot numbers were back to predicted levels during April but sunspot numbers are likely to have fallen back by the end of May. From: http://www.wm7d.net/hamradio/solar/27d_forecast.shtml

Maximum Usable Frequencies
The estimated MUF’s for Western Europe, are 4 MHz (0100-0400), 5 MHz (0500-0600), 6Mhz (0700-1000), 7 MHz (1100-1800), 6 MHz (1900-2200) and 5 MHz (2300-0000). (Times in UTC). This and other regional estimates can be found at: http://hfradio.org/fot_7.html

Sporadic E
The Sporadic E season should be under way from around 1st May. Look for short skip on 15 and 10m. More details about sporadic E and HF propagation can be found in Steve Nichols’ blog and Podcast at: http://g0kya.blogspot.com/
Summertime Sporadic E, or Es as it’s often referred to, is one of the most exciting VHF propagation modes. This is especially true when the MUF reaches 144 MHz. Below is a guide to Summertime Sporadic E, what to listen for and how to work the DX.
What is Sporadic E?
There are three layers to the ionosphere F, D and E. We all know about the importance of the F layer to HF propagation and the way in which it refracts radio waves making world wide communication possible. The D layer and the E layer play little part in this, indeed they can have a detrimental effect to HF conditions by absorbing the transmitted signal before it reaches the F layer. This is particularly true of the E layer when it is heavily ionised.
During the summer months from May to September but in particular June and July, very intense clouds of ionization can occur. While not good for HF it does mean that VHF signals can be refracted by these clouds allowing contacts way in excess of the normal VHF range.
The cause of this intense ionization is unknown and of course very sporadic in nature. But some aspects have a degree of probability and with careful monitoring of the VHF range a good indication of a likely opening can be gained. Openings are more likely to occur early in the morning, early afternoon and in the evening although they can occur at almost any time.
From http://g3vre.org.uk/ES.asp (Chippenham and District ARC)

Solar Cycle Prediction
The current prediction for Sunspot Cycle 24 gives a smoothed sunspot number maximum of about 69 in June of 2013. We are currently over two and a half years into Cycle 24. Two consecutive months with average daily sunspot numbers in the 50s has raised the predicted maximum above the 64.2 for the Cycle 14 maximum in 1907. The predicted size would make this the smallest sunspot cycle in over 100 years.
Predicting the behaviour of a sunspot cycle is fairly reliable once the cycle is well underway (about 3 years after the minimum in sunspot number occurs. Prior to that time the predictions are less reliable but nonetheless equally as important. Planning for satellite orbits and space missions often require knowledge of solar activity levels years in advance. (NASA Solar Physics) http://solarscience.msfc.nasa.gov/predict.shtml
Links to these articles and more can be found at: www.jameswelsh.org.uk

April 2011

2011-03-26T12:02:00.013Z

Propagation Summary

The Solar Flux has reached the100 mark for a total of 15 days during March peaking at 110 from the 13th to the 15th. The Solar flux trend charts at Solarcycle24.com are showing a sharp rise toward the predicted peak of 130 following the dip in mid February. April will start on a high of 100 which should last for around 10 days, peaking at 115 by the 18th. The Boulder A Index has remained fairly steady during March and should remain mostly at 5 during early April. The Boulder K index should stay mainly at 2 as it has done during March. Charts can be found at www.solarcycle24.com . A 28 day forecast from NOAA is updated daily at: http://www.wm7d.net/hamradio/solar/27d_forecast.shtml

Lyrid Meteor Shower

A Lyrid Meteor Shower is due from 19-24 April. However, any Meteor Scatter propagation will depend on where you are in the world. The best time of the year for MS DX’ing is between October and early January. More at: http://www.jt6m.org/meteor-scatter.php

Researchers Crack the Mystery of the Missing Sunspots (NASA Science News)

In 2008-2009, sunspots almost completely disappeared for two years. Solar activity dropped to hundred-year lows; Earth's upper atmosphere cooled and collapsed; the sun’s magnetic field weakened, allowing cosmic rays to penetrate the Solar System in record numbers. It was a big event, and solar physicists openly wondered, where have all the sunspots gone? Now they know. An answer has been published in the March 3rd edition of Nature. Plasma currents deep inside the sun interfered with the formation of sunspots and prolonged solar minimum," says lead author Dibyendu Nandi of the Indian Institute of Science Education and Research in Kolkata. "Our conclusions are based on a new computer model of the sun's interior." For years, solar physicists have recognized the importance of the sun's "Great Conveyor Belt." A vast system of plasma currents called ‘meridional flows’ (akin to ocean currents on Earth) travel along the sun's surface, plunge inward around the poles, and pop up again near the sun's equator. These looping currents play a key role in the 11-year solar cycle.

When sunspots begin to decay, surface currents sweep up their magnetic remains and pull them down inside the star; 300,000 km below the surface, the sun’s magnetic dynamo amplifies the decaying magnetic fields. Re-animated sunspots become buoyant and bob up to the surface like a cork in water. For the first time, Nandi’s team believes they have developed a computer model that gets the physics right for all three aspects of this process--the magnetic dynamo, the conveyor belt, and the buoyant evolution of sunspot magnetic fields. "According to our model, the trouble with sunspots actually began in back in the late 1990s during the upswing of Solar Cycle 23,"

Sunspot cycles of the last century

The thin curve shows the cyclic variation in the number of sunspots. The bars show the cumulative number of sunspot-less days. The minimum of sunspot cycle 23 was the longest in the space age. Credit: Dibyendu Nandi et al NASA Science News 2 March 2011.

Links to these articles can be found at http://www.jameswelsh.org.uk/

March 2011

2011-02-26T03:06:00.003Z

Propagation Summary
The Solar Flux has actually hit the 100 mark in mid February, but had dropped back to 80 by the beginning of March. The Solar Flux should rise to 95 by mid March. The Boulder A index peaked at 25 on the 18th February, dropping back to 5 by the 20th then after peaking at 10 at the beginning of March, it should settle back to the ‘norm’ of 5. The Boulder K Index seems to be the best indicator of SW conditions. If it reaches 5 (like on February 18th) conditions are usually disturbed but, if it drops down to 2, conditions are generally steady. A 24 day forecast can be found at: http://www.wm7d.net/hamradio/solar/27d_forecast.shtml
The Solar flux trend charts at www.solarcycle24.com/flares.htm show that the dip in progress during mid 2010 has recovered but numbers are still well below predicted levels. The Solar flux would need to be averaging at around 110 to reach it’s predicted peak in the first quarter of 2013. There were 260 spotless days in 2009 (70%) compared with just 51 in 2010 (14%).

First X-flare of the New Solar Cycle Earth-orbiting satellites have detected the strongest solar flare in more than four years. At 0156 UT on Feb. 15th, giant sunspot 1158 unleashed an X2-class eruption. X-flares are the strongest type of x-ray flare, and this is the first such eruption of new Solar Cycle 24. The explosion that produced the flare also sent a solar tsunami rippling through the sun's atmosphere and, more importantly, hurled a coronal mass ejection toward Earth. This is likely to have caused the disturbance on February 18th. A Radio Blackout Indicator can be found at www.solarcycle24.com as well as pictures and video of solar activity.

Sunspot Data (Royal Greenwich Observatory)
Sunspots appear as dark spots on the surface of the Sun. They typically last for several days, although very large ones may live for several weeks. Sunspots are magnetic regions on the Sun with magnetic field strengths thousands of times stronger than the Earth's magnetic field. Sunspots usually come in groups with two sets of spots. One set will have positive or north magnetic field while the other set will have negative or south magnetic field. The field is strongest in the darker parts of the sunspots - the umbra. The field is weaker and more horizontal in the lighter part - the penumbra.
The Royal Greenwich Observatory (RGO) compiled sunspot observations from a small network of observatories to produce a data set of daily observations starting in May of 1874. The observatory concluded this data set in 1976 after the US Air Force (USAF) started compiling data from its own Solar Optical Observing Network (SOON). This work was continued with the help of the US National Oceanic and Atmospheric Administration (NOAA) with much of the same information being compiled through to the present. Unfortunately, the more recent data is given in a different format from the original and there are definite changes in the reported parameters from the different sources. In an effort to append the RGO data with the more recent data I have reformatted the USAF and NOAA data to conform to the older RGO data format. The entire data set is available below as ASCII text files containing records for individual years. Each file consists of records with information on individual sunspot groups for each day that spots were observed. The series of data files from 1874-2004 are also available in a single 5.1 Mb ZIP file at: http://solarscience.msfc.nasa.gov/greenwch/RGO_NOAA1874_2004.zip .

Solar Activity MonitorA Solar Activity Monitor can be found at: http://www.n3kl.org/sun/status.html . If you have a website, you can also display the monitor on your web pages.

Acknowledgements to Mike Terry and Ken Fletcher for articles and updates.

February 2011

2011-01-31T18:28:00.005Z

Propagation Summary During January conditions have remained steady and February should remain the same with the Solar Flux mainly at 82. Apart from a slight fluctuation around 3rd February, the Boulder A index is likely to stay at 5 and the K index at 2. www.wm7d.net/hamradio/solar/27d_forecast.shtml

NASA Sun Spot Number predictions revised yet again.
NASA has revised their Sun Spot prediction once again and it is now at the level of the Maunder Minimum of 1675 -1715 when the climate was much colder. The solar cycle 24 predicted sunspot maximum has been reduced again – predicted peak down to 59 Max. Current prediction for the next sunspot cycle maximum gives a smoothed sunspot number maximum of about 59 in June/July of 2013. We are currently two years into Cycle 24 and the predicted size continues to fall. (NASA Solar Physics, 3 January 2011. http://solarscience.msfc.nasa.gov/predict.shtml )

Cycle 24 Continues “During the course of an approximate eleven year sunspot cycle, the minimum phase, or quiet sun, is generally considered to exist during the time when the smoothed sunspot number (SSN) drops, and remains below 30. The smoothed sunspot number is a monthly index compiled by the Royal Observatory of Belgium for measuring solar cycle progress.
An unbroken string of smoothed sunspot numbers has been recorded since 1750. The present period of quiet sun began as declining Cycle 23 dropped below the SSN 30 level during April, 2005. A period of moderate solar activity is expected for the remainder of 2011, reaching a sunspot count on the order of 60 by year's end. This six-year solar quiet period was the deepest and most persistent recorded in almost two hundred years. It mystified solar scientists, and it is another example of how little is yet known about sunspots and of the nature of the Sun itself.” (George Jacobs WRTH 2011)

Say Goodbye To Sunspots ?“Scientists studying sunspots for the past 2 decades have concluded that the magnetic field that triggers their formation has been steadily declining. If the current trend continues, by 2016 the sun's face may become spotless and remain that way for decades—a phenomenon that in the 17th century coincided with a prolonged period of cooling on Earth.
The last solar minimum should have ended last year, but something peculiar has been happening. Although solar minimums normally last about 16 months, the current one has stretched over 26 months—the longest in a century. One reason, according to a paper submitted to the International Astronomical Union Symposium No. 273, an online colloquium, is that the magnetic field strength of sunspots appears to be waning. “
( http://news.sciencemag.org/sciencenow/2010/09/say-goodbye-to-sunspots.html )

Sunspots may vanish by 2015. By William Livingston, and Matthew Penn.
“We have observed spectroscopic changes in temperature sensitive molecular lines, in the magnetic splitting of an Fe I line, and in the continuum brightness of over 1000 sunspot umbrae from 1990-2005. All three measurements show consistent trends in which the darkest parts of the sunspot umbra have become warmer (45K per year) and their magnetic field strengths have decreased (77 Gauss per year), independently of the normal 11-year sunspot cycle. A linear extrapolation of these trends suggests that few sunspots will be visible after 2015.”
This article can be viewed in PDF format at: http://wattsupwiththat.files.wordpress.com/2008/06/livingston-penn_sunspots2.pdf

Thanks to Ken Fletcher and Mike Terry for this month’s articles. Links to these articles can be found at: www.jameswelsh.org.uk

January 2011

2010-12-30T01:03:00.005Z

Propagation Summary

Sunspot numbers have progressively dropped since 2002 with the lowest numbers recorded in 2008. However, since 2009 there has been a upward trend but the Solar Flux progression charts at http://solarcycle24.com/flux.htm still show the sunspot numbers to be consistently lower than predicted. There are more historical charts at: http://wm7d.net/hamradio/solar/historical.shtml
January’s Solar activity is predicted to be on yet another downward trend. The Solar Flux is forecast to drop from 90 to 80 during January. The Boulder A index will stay at 5, except for 4 - 6 and 20 - 21 January. The Boulder A index is likely to remain at a steady 2 for this period.

Global Eruption Rocks the Sun

On August 1, 2010, an entire hemisphere of the sun erupted. Filaments of magnetism snapped and exploded, shock waves raced across the stellar surface, billion-ton clouds of hot gas billowed into space. "The August 1st event really opened our eyes," says Karel Schrijver of Lockheed Martin's Solar and Astrophysics Lab in Palo Alto, CA. "We see that solar storms can be global events, playing out on scales we scarcely imagined before." "The whole-sun approach could lead to breakthroughs in predicting solar activity," commented Rodney Viereck of NOAA's Space Weather Prediction Centre in Boulder, CO. "To predict eruptions we can no longer focus on the magnetic fields of isolated active regions," says Title, "we have to know the surface magnetic field of practically the entire sun." This revelation increases the work load for space weather forecasters, but it also increases the potential accuracy of their forecasts
(NASA Science News. 6 December 2010).

NASA Solar Shield Project

Solar storms don’t just affect radio propagation. Every hundred years or so, a solar storm comes along so potent it fills the skies of Earth with blood-red auroras, makes compass needles point in the wrong direction, and sends electric currents coursing through the planet's topsoil. The most famous such storm, the Carrington Event of 1859, actually shocked telegraph operators and set some of their offices on fire. A 2008 report by the National Academy of Sciences warns that if such a storm occurred today, we could experience widespread power blackouts with permanent damage to many key transformers. Solar Shield is a new and experimental forecasting system for the North American power grid," explains project leader Antti Pulkkinen, a Catholic University of America research associate working at NASA's Goddard Space Flight Centre. "We believe we can zero in on specific transformers and predict which of them are going to be hit hardest by a space weather event."
The troublemaker for power grids is the "GIC" – short for geomagnetically induced current. When a coronal mass ejection (a billion-ton solar storm cloud) hits Earth's magnetic field, the impact causes the field to shake and quiver. These magnetic vibrations induce currents almost everywhere, from Earth's upper atmosphere to the ground beneath our feet. Powerful GICs can overload circuits, trip breakers, and in extreme cases melt the windings of heavy-duty transformers.
This actually happened in Quebec on March 13, 1989, when a geomagnetic storm much less severe than the Carrington Event knocked out power across the entire province for more than nine hours. The storm damaged transformers in Quebec, New Jersey, and Great Britain, and caused more than 200 power anomalies across the USA from the eastern seaboard to the Pacific Northwest. A similar series of storms in October 2003 triggered a regional blackout in southern Sweden and may have damaged transformers in South Africa. Pulkkinen stresses that Solar Shield is experimental and has never been field-tested during a severe geomagnetic storm.
“The more data we can collect from the field, the faster we can test and improve Solar Shield. The next solar maximum is expected around 2013, so it's only a matter of time.“ Full article at: http://science.nasa.gov/science-news/science-at-nasa/2010/26oct_solarshield/

November 2010

2010-10-23T03:06:00.004+01:00

Propagation Summary
Conditions have remained fairly steady during October. The solar Flux actually reached 90 on the 20th, but it should fall to 75 by November 1st then rise again to 85 by mid November. The Boulder A index should stay at 5 and the K index at 2 during the first half of November. So far during 2010, there have been 45 spotless days (15%) , compared 260 in 2009 (71%). http://www.wm7d.net/hamradio/solar/27d_forecast.shtml )

Meteor Showers
Earth is passing through a stream of debris from Halley's Comet, and this is causing the annual Orionid meteor shower. Bright moonlight is reducing the number of visible meteors; nevertheless, sky watchers are reporting some bright Orionids.
Meteor showers provide a very significant increase in the number of meteor trails that can be used for radio communications. These showers arrive at fixed times of the year, appearing on an annual basis. Some are small, whereas others are much larger and can last for several days. There are hundreds or possibly even thousands of these showers. The smaller showers are not easy to distinguish, but some of the larger showers produce a spectacular display if their occurrence coincides with a clear night.
When a meteor shower is observed it will be seen that the meteors appear to come from a single point in the sky which is known as the "radiant". This is a perspective effect caused by the fact that all the particles enter the Earth's atmosphere parallel to one another. The radiant gives rise to the name of the shower - the Perseids shower has its radiant in the constellation of Perseus.
Showers are caused by groups of particles orbiting the Sun in an elliptical orbit. Usually they are associated with comets which leave their debris behind them. Although not all meteor showers have been linked to particular comets, it is thought that all showers come from this source.
Showers vary in intensity from one year to the next. This happens because the particles are not evenly spread around their orbit. One of the most reliable and constant showers is the Perseids shower, but even this one shows some significant variations from one year to the next.
Meteor showers forecast for November are:
Taurids from 25 October to 25 November peaking on November 4th. Leonids: 15 - 19 November peaking on the 17th. Cephids 7 - 9 November peaking on the 11th More details at: http://surf.to/meteorscatter See also: http://stardate.org/nightsky/meteors and: www.spaceweather.com (Via Mike Terry)

DX Info Centre
Here is a website all about FM and UHF DX’ing. Subjects covered included are Tropospheric Ducting and E Skip. There are also many world maps showing colour coded event forecasts, plus links to other relevant websites: www.dxinfocentre.com/

Links to these articles and more can be found at: www.jameswelsh.org.uk

October 2010

2010-09-23T03:22:00.007+01:00

Propagation Summary
Conditions have remained fairly steady during September. October should begin quiet apart from a slight disturbance on the 5th and the 12th . The Boulder A index is peaking at around 10 every 7 days, and the K index is varying between 2 and 3 during these peaks. Sunspot numbers have remained around the 80 mark during August and September. October should remain the same. According to the trend charts at Solar Cycle 24.com, the Solar flux is forecast to reach 100 by the end of 2010, but after a drop in mid 2010, numbers have continued to remain at around 80 and if this trend continues, it will not reach the predicted peak of 140 by 2014.

Solar Storms can Change Directions, Surprising Forecasters
Solar storms don't always travel in a straight line. But once they start heading in our direction, they can accelerate rapidly, gathering steam for a harder hit on Earth's magnetic field.
So say researchers who have been using data from NASA's twin STEREO spacecraft to unravel the 3D structure of solar storms.
Their findings are presented in Nature Communications. Magazine "This really surprised us," says co-author Peter Gallagher of Trinity College in Dublin. "Solar coronal mass ejections (CMEs) can start out going one way—and then turn in a different direction." The result was so strange, at first they thought they'd done something wrong. After double- and triple-checking their work on dozens of eruptions, however, the team knew they were onto something. The sun's global magnetic field, which is shaped like a bar magnet, guides the wayward CMEs back toward the sun's equator. When the clouds reach low latitudes, they get caught up in the solar wind and head out toward the planets—"like a cork bobbing along a
river," says Gallagher. (NASA Science News 21 September 2010)

Solar Probe to Plunge Directly into Sun's Atmosphere
NASA's plan to visit the sun took a leap forward today with the selection of five key science investigations for the Solar Probe spacecraft. Slated to launch no later than 2018, the smart car-sized spacecraft will plunge directly into the atmosphere of the sun, aiming to solve some of the biggest mysteries of solar physics. This means that researchers can begin building sensors for ‘in situ’ measurements of the solar system's innermost frontier. Lika Guhathakurta, NASA Solar Probe Programme scientist said: "For the first time, we'll be able to 'touch, taste and smell' the sun." Last year, NASA invited top researchers around the world to submit proposals detailing possible science investigations for the pioneering spacecraft. More details at: NASA Science News

About Sunspot Cycles
Dark spots appear at places on the Sun where its magnetic field is concentrated. The number of sunspots is controlled by the amount of distortion of the Sun's magnetic field. The magnetic field becomes distorted because the Sun's equator and core rotate more quickly than its other parts. As a result, sunspot activity varies over an average 11-year cycle. During this period, the Sun goes from a solar minimum (fewer spots) to a solar maximum (more spots) and back to a minimum again. The solar magnetic activity cycle is the main source of the ~10.7 year periodic solar variation, which drives variations in space weather and to some degree weather on the ground and possibly climate change. (BBC article via Ken Fletcher)
Thanks to Ken Fletcher and Mike Terry for regular updates.

September 2010

2010-08-18T17:04:00.005+01:00

Propagation Summary
August has been an interesting month with a massive M1 Solar Flare on August 7th which narrowly missed earth and resulted in the Northern Lights being visible as far south as Iowa, USA. A Persuid meteor shower also passed the Earth over a few days around 12th August which was actually visible to the naked eye in some parts of the world, which should have produced some interesting results for Radio Amateurs. (The next Persuid Meteor shower is forecast for 5-17 September, peaking on the 9th. http://www.imo.net/calendar/2010#julsep )

The NOAA report that On Saturday, August 14, 2010 a small solar flare erupted on the Sun at about 6am EDT. Associated with this flare was a coronal mass ejection (CME) that was partially directed towards the Earth. Also associated with this event was a S1 or minor solar radiation storm on the NOAA Space Weather Scales. The only impacts expected for a solar radiation storm of this magnitude are minor impacts to HF radio communications in the polar regions. However, this is the first solar radiation storm of Solar Cycle 24 and the first solar radiation storm since December of 2006. http://www.swpc.noaa.gov/ .

However, the sunspot number progression chart at Solarcycle24.com still shows sunspot activity to be actually lower than predicted. ( http://solarcycle24.com/sunspots.htm ) Apart from a noticeable disturbance around the 23rd, August should end with relatively steady conditions with the Boulder A index at 5 and the K index at 2, and is forecast to remain the same until mid September. The Solar Flux is forecast to return to a steady 85 during this period. WM7D.net

Solar Cycle 25
Peaking around 2022, Solar Cycle 25 could be one of the weakest in centuries.
The Sun's Great Conveyor Belt has slowed to a record-low crawl, according to research by NASA solar physicist David Hathaway. "It's off the bottom of the charts," he says. "This has important repercussions for future solar activity." http://www.physorg.com/news66581392.html

Radio Fadeouts and Solar Flares
Solar flares produce copious amounts of electromagnetic radiation, the X-ray component of which increases the ionisation of the ionospheric D layer. HF communication generally depends on the reflection of signals from the higher F layer and such signals must travel through the D layer at least twice. Increased ionisation results in greater absorption of the signal in the D layer.
This effect is known as a short-wave fadeout (SWF) and is observed as an increased attenuation of HF signals particularly at the lower frequencies. The fadeout follows closely the pattern of the solar flare, being observed at the same time as the flare. Fadeouts mostly have a rapid onset of a few minutes and a slower decline lasting perhaps an hour (this is highly variable).
A property of SWFs is that they affect the lower HF frequencies more than the higher ones which may not be affected at all. The high frequencies are the last to be affected and the first to recover.
An important feature of SWFs is that the HF circuit is affected only if there is an ionospheric reflection point for the signal in the sunlit hemisphere. No effect is observed if all the reflection points are located in the night hemisphere which is shadowed from the X-rays from the flare.
The intensity of flares at X-ray wavelengths allows us to estimate the extent (both geographical and in frequency) of a fadeout. This intensity is now measured by satellite and so IPS has established a page on the Internet to show the extent of fadeouts in near real-time at:
http://www.ips.gov.au/HF_Systems/6/2/1

Links to these articles and more can be found at www.jameswelsh.org.uk

August 2010

2010-07-24T13:36:00.003+01:00

Propagation Summary
Conditions have remained the same during July, apart from the slight disturbance between the 23rd and the 28th (Sunspot Number 1084) during which the Boulder A index will have gone as high as 15 and the K index wil have hit 5. The Solar Flux will have dropped to 72 by 1st August, returning to it’s the recent ‘norm’ of 80 by the August 6th. ( From: http://www.wm7d.net/hamradio/solar/27d_forecast.shtml )
Sunspot numbers are still around 50% below the targets forecast by Solarcycle24.com (http://solarcycle24.com/sunspots.htm ) See also Steve Nichols’ UK Short Path Propagation Forecast at: http://www.infotechcomms.net/propcharts/

Steve Nichol (GOKYA) ‘s Propagation Forecast
“Some people have suggested that the bands are improving, but I think they are confusing Sporadic E (Es) openings with F layer. This seasonal effect is opening up 20-10m and even 6m and 2m with good, strong openings up to 1,300 miles.
Multi-hop Es is stretching this even further, but we are not seeing an improvement in F layer propagation and Es will be less prevalent as the summer wears on.
Mid-to-late September will be the acid test – and with flux levels in the 70s we are not going to see many trans-Atlantic openings on 10m. Sorry!

20m (14MHz) is likely to be the best DX band between sunrise and sunset, although the band will be noisier than the winter period and not as reliable for long-haul contacts. The higher MUFs at night mean that 20m may remain open during the evening to DX. Short skip may also be possible due to summer sporadic-E.” http://www.g0kya.blogspot.com/

All About Sporadic E
“Sporadic E is irregular scattered patches of relatively dense ionization that develop seasonally within the E region and that reflect and scatter radio frequencies up to 150 MHz. Sporadic E is a regular daytime occurrence over the equatorial regions and is common in the temperate latitudes in late spring ,early summer and, to a lesser degree, in early winter. At high, i.e., polar, latitudes, Sporadic E can accompany Auroras and associated disturbed magnetic conditions. It can sometimes support reflections for distances up to 2,400 km.
Sporadic E is a form of propagation that can arise with little warning, and enable radio frequencies of 150 MHz and more to travel over distances of a thousand kilometres and more. Many people will have experienced it in the days of the old VHF TV transmissions.
When sporadic E propagation arose, it would result in severe interference to the signals. Even now VHF FM broadcasts in the 88 - 108 MHz band can be affected. In many instances the arrival of Sporadic E can cause unwanted interference as signals that are normally too distant to be heard appear. possible.
Sporadic E arises when clouds of intense ionisation form in the region of the E layer. These clouds can have very high levels of ionisation, allowing frequencies up to about 150 MHz to be reflected on some occasions. The clouds are usually comparatively small, measuring only about 50 to 150 kilometres in diameter. Their shape is irregular. Sometimes they may be almost circular, whereas others may be long and thin. They are also surprisingly thin, often only measuring a few hundred metres in depth.
These clouds appear almost at random, although there are times when they are more likely to occur. They form in the day, and dissipate within a few hours. You can read the complete article at:
http://www.g4xgt.co.uk/what-is-sporadic-e.htm
There are also some extra Sporadic E related links and more at: www.jameswelsh.org.uk

July 2010

2010-06-26T03:53:00.003+01:00

Propagation Summary
Conditions have remained the same during June except for a fluctuation around the 26th which seems to be happening roughly every 16 days. As far as the Boulder A and K indices are concerned, the ‘floor’ levels are 5 and 2 respectively. The A index rises to between 10 and 15, and the K index rises from 2 to 3 during these fluctuations, the next one being around 13th July . The Solar flux however, is once again on a downward trend. The solar flux is expected to be 75 at the end of June, dropping to 70 by June 19th.

Solar Storm Watch
This is a project by the Royal Observatory an Greenwich where the public are invited to take part in predicting the direction of Coronal Mass Ejections on the sun from online diagrams and videos. The method is known as crowd sourcing. Scientist Chris Davies said: “The reason that we want lots of people doing this is because that takes away the subjectivity. If we have a consensus view of what a CME looks like and which way it's going then you can be much more confident about that answer being correct.” Anybody can take part by registering at: www.solarstormwatch.com (Via Ken Fletcher).

Sunspots may vanish by 2015. By William Livingston and Matthew Penn.

“We have observed spectroscopic changes in temperature sensitive molecular lines, in the magnetic splitting of an Fe I line, and in the continuum brightness of over 1000 sunspot umbrae from 1990-2005. All three measurements show consistent trends in which the darkest parts of the sunspot umbra have become warmer (45K per year) and their magnetic field strengths have decreased (77 Gauss per year), independently of the normal 11-year sunspot cycle. A linear extrapolation of these trends suggests that few sunspots will be visible after 2015. Sunspots are cool dark regions on the solar surface with strong magnetic fields. There have been few direct measurements of changes in the physical parameters of sunspots, but here we present a study which shows that sunspots are becoming warmer and have weaker magnetic fields. The number of sunspots visible on the Sun normally shows an 11-year periodicity, and the current sunspot cycle (cycle 23) had a maximum in 2001, and is entering a minimum phase with few sunspots currently visible. Our data show that there are additional changes occurring in sunspots, independent of the sunspot cycle, and these trends suggest that sunspots will disappear completely.” (National Solar Observatory Tucson, Arizona) This report can be viewed in full at:
http://wattsupwiththat.files.wordpress.com/2008/06/livingston-penn_sunspots2.pdf (Alerted by Glenn Hauser, in his latest World of Radio: www.worldofradio.com)

Solar Dynamics Observatory delivers stunning images
The Solar Dynamics Observatory (SDO) is returning stunning pictures of the sun.
Launched February 11, it carries six image sensors from UK company e2v based in Chelmsford, Essex.
NASA's Solar Dynamics Observatory is returning early images that confirm an unprecedented new capability for scientists to better understand our sun’s dynamic processes.
Some of the images from the spacecraft show never-before-seen detail of material streaming outward and away from sunspots. Others show extreme close-ups of activity on the sun’s surface.
The spacecraft also has made the first high-resolution measurements of solar flares in a broad range of extreme ultraviolet wavelengths. "These initial images show a dynamic sun that I had never seen in more than 40 years of solar research,” said Richard Fisher, director of the Heliophysics Division at NASA Headquarters in Washington. "SDO will change our understanding of the sun and its processes, which affect our lives and society. This mission will have a huge impact on science, similar to the impact of the Hubble Space Telescope on modern astrophysics.”
‘A Solar Prominence’ is a video of the March 30, 2010 prominence eruption, starting with a zoomed in view. The twisting motion of the material is the most noticeable feature. The viewpoint then pulls out to show the entire Sun.
Watch it at: http://www.nasa.gov/mov/445814main_Pesnell_7-Prominence-H264.mov
Other SDO images at
http://www.nasa.gov/mission_pages/sdo/news/briefing-materials-20100421.html

NASA's New Eye on the Sun Delivers Stunning First Images
http://www.nasa.gov/mission_pages/sdo/news/first-light.html

Successful launch for SDO
http://www.southgatearc.org/news/february2010/
sdo_launched.htm

This was also featured on News Briefing BBC Radio 4 22nd April 2010.
(Via Ken Fletcher with thanks to Mike Terry and Southgate ARC)

June 2010

2010-05-19T01:45:00.002+01:00

Propagation Summary
The bank Holiday weekend of 29-30 May will have seen a noticeable disturbance of HF reception with the Boulder A index as high as 25 and the K index at 5. The first half of June should be fairly calm with the A index at 5 and the K index at 2. The Solar flux will go from 80 down to 70 during this period. .Maximum Useable frequencies for June are likely to remain between 6 and 7 Mhz. (http://www.wm7d.net/hamradio/solar/27d_forecast.shtml) Comprehensive forecasts and summaries, including charts and satellite images can also be found at: (http://prop.hfradio.org/)

HF Propagation Report May 2010“Solar conditions have not been very good in the last month. In fact we had a run of about 12 days without a single sunspot. With the solar flux hovering around 74 it was like a return to the minimum once again. Solar flare activity has been low, but even a small change in the Interplanetary Magnetic Field (Bz) swinging south was enough to cause the HF bands to misbehave.” More details in G0KYA's Amateur Radio Blog: http://www.g0kya.blogspot.com/
(Via Mike Terry)

Sunspot Numbers Are Lower Than Forecast
The Sunspot trend charts on Solarcycle 24.com, are showing a significant drop in sunspot activity in the first quarter of 2010. The smoothed average sunspot forecast for the end of April, for example is 25 but the actual figure for April is as low as 10. The Sunspot trend charts and more can be viewed at: http://solarcycle24.com/sunspots.htm

First Light for the Solar Dynamics Observatory.
NASA's Solar Dynamics Observatory is beaming back stunning new images of the sun, revealing our own star as never seen before. Even veteran solar physicists say they are amazed by the data. At a press conference in Washington DC 21at April,, researchers unveiled "First Light" images from NASA's Solar Dynamics Observatory, a space telescope designed to study the sun.
"SDO is working beautifully," reports project scientist Dean Pesnell of the Goddard Space Flight Centre. "This is even better than we could have dreamed." Launched on February 11th from Cape Canaveral, the observatory has spent the past two months moving into a geosynchronious orbit and activating its instruments. As soon as SDO's telescope doors opened, the spacecraft began beaming back scenes so beautiful and puzzlingly complex that even seasoned observers were stunned.
"We've seen solar prominences before—but never quite like this," says Alan Title of Lockheed Martin, principal investigator of the Atmospheric Imaging Assembly (AIA), the observatory's main telescope array. "Some of my colleagues say they've learned new things about prominences just by watching this one movie." SDO is the first mission of NASA's Living with a Star (LWS) program. The goal of LWS is to understand the sun as a magnetic variable star and to measure its impact on life and society on Earth. Program scientist Like Guhathakurta of NASA headquarters envisions big things for the new observatory:
"SDO is our 'Hubble for the sun'," she says. "It promises to transform solar physics in the same way the Hubble Space Telescope has transformed astronomy and cosmology." "No solar telescope has ever come close to the combined spatial, temporal and spectral resolution of SDO," adds Title. "This is possible because of the combination of 4096 x 4096-pixel CCDs with huge dynamic range and a geosynchronious orbit which allows SDO to observe the sun and communicate with the ground around the clock." More details including up to date pictures and video can be found at: http://sohowww.nascom.nasa.gov/pickoftheweek/
Thanks to Ken Fletcher and Mike Terry for regular updates.
Links: www.jameswelsh.org.uk

May 2010

2010-04-24T13:25:00.003+01:00

Propagation Summary
April has remained fairly quiet with occasional disturbances. May should remain the same with a possible disturbance on the 4th and 5th. The Solar Flux is fluctuating between 75 and 84, roughly every 7 days. The Boulder A index is fluctuating in a similar way between 5 and 8, and the K index is likely to remain between 2 and 3 in a similar pattern during May. Conditions are forecast to remain mainly quiet with a 50% probability of C class flares.( http://prop.hfradio.org/ ) Maximum useable frequencies are likely to remain between 6 and 7 Megs during daylight hours.(http://hfradio.org/fot_7.html)

The May report in the Communication Journal has been reduced due to publication of Broadcasts In English

Thanks to Ken Fletcher and Mike Terry for regular updates.

April '10

2010-03-26T14:31:00.005Z

Propagation Summary Conditions continued to improve during March, and the Solar Flux has continued to rise but the predicted CME (Coronal Mass Ejection), which was forecast for 17th March had no noticeable affect on conditions. Another minor Solar CME is forecast for 4th April.
(http://www.solen.info/solar/indices.html)

The Boulder A index should stay at a steady 5 during most of April except on the 7th and 8th when it will rise to 5. The K index is forecast to remain at 2 for this period again rising by just one point on 7-8 April. The Solar Flux will start out at 85, rising to 90 by the 3rd and dropping to 80 by April 19th. (http://www.wm7d.net/hamradio/solar/27d_forecast.shtml)

Solar activity is expected to be very low with possible isolated periods of low levels during the forecast period. Quiet conditions are expected to prevail for the remainder of the interval from 09-19 April. Updated forecasts are available at: (http://www.swpc.noaa.gov/ftpdir/weekly/WKHF.txt)

Maximum Useable Frequencies for Western Europe should be around 7 Megs during daylight hours.
Further details and other regional data can be found at: (http://hfradio.org/fot_7.html)

Improving Shortwave Conditions. At Last we seem to be emerging from a Long 'Low Sunspot' Period. A combination of this, with longer hours of Daylight should see some overall improvement, especially on higher frequencies. (With thanks to Glenn Hauser, Higher Solar Flux reported, BDXC-UK and George Jacobs WRTVH 2010) Ken Fletcher

2010 Lyrid Meteor Shower Activity
The Lyrids are active from April 16 through the 25th. Peak rates for this shower occur on the 22nd when rates can approach fifteen Lyrids per hour. Five Lyrids per hour can appear on the 21st and the 23rd. Away from these three nights, the Lyrids are weak, only producing 1-2 each hour.
At the time of maximum activity the Lyrid radiant is actually located in eastern Hercules, seven degrees south west of the brilliant star Vega (Alpha Lyrae). This area of the sky lies below the horizon during the early evening hours. Therefore no Lyrid activity can be seen until the late evening hours. The radiant attains a decent elevation between midnight and 0100, depending on your latitude. It is best situated high in a dark sky just before the start of morning twilight. Your best rates will occur during the last dark hour before dawn. (http://www.amsmeteors.org/showers.html)

AM Interference“The radio noise problem is as old as radio itself. Unfortunately it is getting worse as technology steadily progresses and more man-made electronic products hit the shelves. This is a direct result of mainly consumer products that generate an increasingly higher noise level. The technology behind the AM broadcast signal is very out-dated as far as current technology is concerned, not to mention that the AM broadcast band is located in the very vulnerable medium wave frequency band.”
This article by Chris Justice about AM interference explains some of the sources of interference such as Fluorescent Lights, Dimmer Switches, Computers and TV's. Various solutions to eliminate these problems are included as well as some inexpensive antenna solutions. The full article can be found at: (http://www.radiolabs.com/Articles/amnoise.html)

March 2010

2010-02-26T18:29:00.004Z

Propagation Summary
Conditions have remained fairly steady during February, except for 11-14th when the A index peaked at 13 and the K at 3. This had settled back to normal by the 18th, with the A Index mainly at 5 and the K Index at 2. March, however, will start off with a similar burst of Solar activity. The Solar Flux is now definitely on the up and should once again reach the 90 mark for up to 6 days from around 7th March.
(http://wm7d.net/hamradio/solar/)

Solar Activity Could Disrupt the 2012 Olympics On February 12th, scientists warned that a peak in solar activity is due to occur in 2012, risking the disruption of television and internet networks during the London Olympic Games. "The Olympics could be bang in the middle of a solar maximum," said Richard Harrison, of the Rutherford Appleton Laboratory, Oxfordshire, speaking before the launch this week of Nasa's Solar Dynamics Observatory. It has long been known that surges in solar activity can cause disruption in satellite and terrestrial communications systems, but, until now, it has been almost impossible to predict solar storms in advance. Following the launch of Nasa's solar observatory, scientists now say that they will be able to give warning of magnetic storms and solar flares. By turning off sensitive electronic circuits before a storm, damage to satellite transmitters, and the resulting disruption, could be minimised. The Nasa probe, launched in early February from Cape Canaveral, will spend five years in orbit around the Earth, investigating the causes of extreme activity, such as sun spots, solar winds and violent eruptions from the Sun's atmosphere known as coronal mass ejections. Professor Harrison said "Such events can expose astronauts to deadly particle doses, can disable satellites, cause power grid failures on Earth and disrupt communications,".
Hannah Devlin (The Times) 3 February 2010 via Mike Terry.

GPS Inaccurate During Space Storms. In bad weather, it can be hard to tell where you are. It turns out that your GPS unit may not be entirely sure, either, if the weather in space is bad. It is now known that space weather, specifically electrical disturbances in our planet's ionosphere can throw off the accuracy of GPS units appreciably. Scientists are working to remedy the situation. GPS units calculate their locations by analyzing signals from a dedicated group of satellites, but those signals can be delayed or distorted while passing through the ionosphere, explained Anthea Coster, an atmospheric scientist at MIT. During sunspot activity, the inaccuracy can exceed 32 yards (30 meters). "People think the problem has been solved, but they have been lulled because the 11-year sunspot cycle is currently at its minimum," she told SPACE.com. "That will change in about two years." Excited by sunspots, the ionosphere has been known to produce "fingers" of heavy ionization nearly 150 miles wide extending from Florida across Canada to the North Pole, she said: Space storms, sometimes caused by sunspot activity, are also known to zap cell towers, causing dropped calls. Strong solar flares can disrupt all types of communications on Earth, including GPS, and even disable satellites.
(Full article at: http://www.livescience.com/space/080618-tw-gps-space-weather.html)

All About Solar Flares A solar flare is a thunderous explosion that occurs in the solar corona and chromosphere within the atmosphere of the Sun. The incredible energy level of a solar flare is equivalent to tens of millions of atomic bombs exploding at the same time! Solar flares were first known to be occurring in 1859. Solar flare activity can vary from several per day to only a few a month, depending mostly upon the overall activity of the Sun as a whole. Solar activity generally varies on an 11-year cycle. At the peak of this “solar cycle” there are typically more sunspots on the surface of the Sun, which ultimately leads to more frequently occurring solar flares. Solar flares are typically classified as A, B, C, M or X, depending upon the degree of their peak flux. Most solar flares occur in or around sun spots as the result of intense magnetic fields emerging from the Sun’s surface into the corona. The powerful energy commonly associated with solar flares can take as long as several days to build up, but only minutes to release. During the occurrence of a solar flare, plasma is heated to tens of millions degrees, while electrons, protons and heavier ions are accelerated to near the speed of light. Solar flares produce electromagnetic radiation across the electromagnetic spectrum at all wavelengths from long-wave radio to the shortest wavelength Gamma rays. Solar flares cannot typically be detected by the naked eye from the surface of the earth. (From: http://www.space.com/solar-flares/)
Thanks to Mike Terry and Ken Fletcher for updates.

February '10

2010-01-29T18:00:00.004Z

Propagation Forecast
Conditions have remained calm during January, except for a minor disturbance on 20 January caused by Sunspot 1039 which emerged on the far side of the sun on the 19th. Conditions are likely to remain calm until February 16th when a similar disturbance may affect radio propagation. Maximum A index will be 10, returning to the norm of 5 within 2 days. The Boulder K index has remained at 2 during the last 4 weeks rising by 1 point during sunspot activity. The solar Flux is now on a steady upward trend, rising to 84 by 16th February. This is a definite sign of Solar cycle 24 emerging at last. Maximum usablefrequencies during February should remain at between 6 and 7 MHz. http://www.wm7d.net/hamradio/solar/27d_forecast.shtml

Solar Conditions and Global Temperatures
In This NASA article, John Hansen, director of GISS (Goddard Institute for Space Studies) explains a link between Global temperatures and Solar activity.
“Although 2008 was the coolest year of the decade , due to strong cooling of the tropical Pacific Ocean 2009 saw a return to near-record global temperatures. The past year was only a fraction of a degree cooler than 2005, the warmest year on record, and tied with a cluster of other years -- 1998, 2002, 2003, 2006 and 2007 -- as the second warmest year since record keeping began.
A deep solar minimum has made sunspots a rarity in the last few years. Such lulls in solar activity, which can cause the total amount of energy given off by the sun to decrease by about a tenth of a percent, typically spur surface temperature to dip slightly. Overall, solar minimums and maximums are thought to produce no more than 0.1°C (0.18°F) of cooling or warming.
“In 2009, it was clear that even the deepest solar minimum in the period of satellite data hasn’t stopped global warming from continuing,” said Hansen. (From: http://www.nasa.gov/topics/earth/features/temp-analysis-2009.html)

Geomagnetic Storm Levels
The Boulder K Index is the best indicator of solar activity.
Geomagnetic storm levels are determined by the estimated 3-hourly Planetary K-indices which are that are derived in real time from a network of western hemisphere ground-based magnetometers. Geomagnetic storm level. During 2009, the K Index has occasionally reached 5 and will probably exceed this during 2010, as we enter Solar Cycle 24.
Planetary K
Indices Geomagnetic/Storm Level
K=5 G1
K=6 G2
K=7 G3
K=8 G4
K=9 G5

http://www.nohr.com

Solar Flare Images
The Scientific front Line website shows video images of a Solar Flare in 2003 recorded by the SOHO (Solar and Heliospheric Observatory) Satellite. These are similar to the solar activity we can expect from Solar Cycle 24. ( http://www.sflorg.com/spaceweather/news/sw041808_01.html )

Meteor Showers in 2010
Meteor showers are produced by small fragments of cosmic debris entering the earth's atmosphere at extremely high speed. Apart from being used in ham radio circles, meteor scatter communications is also used in professional and commercial radio communications applications. It provides a relatively low cost and reliable form of radio communication for medium distances provided that real time data transfer is not required. It is used for radio communications applications such as sending data from remote weather stations and for oil rigs where it provides a useful element of their data communications structure.
2010 began with the intense but brief Quadrantid maximum (January 3/4). The Lyrids past mid-April (max: April 22/23) will raise meteor rates for several nights. The Eta Aquarids (max: May 7/8) enrich late nights of May's first half, sometimes substantially. February, March, and April evenings have another notable feature. An unusual number of sporadic fireballs come in this interval, possibly one every few nights. June to mid-July has fair rates. The last half of July has rates increasing steadily as the Delta Aquarids (July 29/30) and Alpha Capricornids (July 27-28) have maxima at month's end. Even the Perseids are beginning to show a little. Overall, late July to mid-August is very rich in meteors. The Perseid maximum, just before mid-August (August 12/13), is fairly prolonged and quite rich. (http://www.amsmeteors.org/showers.html )

Propagation January 2010

2010-01-01T18:32:00.003Z

Propagation Forecast
January is likely to remain fairly calm with the Boulder A index remaining at 5 and the K index at 2 throughout the month. The Solar flux will start at 80 and should drop to 76 by the end of the month. The http://www.wm7d.net/hamradio/solar/27d_forecast.shtml Maximum Useable frequencies Western Europe for daylight hours in January are 6-7 MHz. http://hfradio.org/fot_7.html

2009 has seen a total of 209 days of zero sunspot activity (71%), according to Spaceweather.com and is estimated to be the 5th most spotless year since 1849. http://anhonestclimatedebate.wordpress.com/category/sunspots/

Solar Cycle Prediction
A number of techniques are used to predict the amplitude of a cycle during the time near and before sunspot minimum. Relationships have been found between the size of the next cycle maximum and the length of the previous cycle, the level of activity at sunspot minimum, and the size of the previous cycle.

Predicting the behaviour of a sunspot cycle is fairly reliable once the cycle is well underway (about 3 years after the minimum in sunspot number occurs. Prior to that time the predictions are less reliable but nonetheless equally as important. Planning for satellite orbits and space missions often require knowledge of solar activity levels years in advance. A number of techniques are used to predict the amplitude of a cycle during the time near and before sunspot minimum. Relationships have been found between the size of the next cycle maximum and the length of the previous cycle, the level of activity at sunspot minimum, and the size of the previous cycle.

Among the most reliable techniques are those that use the measurements of changes in the Earth's magnetic field at, and before, sunspot minimum. These changes in the Earth's magnetic field are known to be caused by solar storms but the precise connections between them and future solar activity levels is still uncertain.

Of these "geomagnetic precursor" techniques three stand out. The earliest is from Ohl and Ohl [Solar-Terrestrial Predictions Proceedings, Vol. II. 258 (1979)] They found that the value of the geomagnetic A index at its minimum was related to the sunspot number during the ensuing maximum. The primary disadvantage of this technique is that the minimum in the geomagnetic A index often occurs slightly after sunspot minimum so the prediction isn't available until the sunspot cycle has started.

An alternative method is due to a process suggested by Joan Feynman. She separates the geomagnetic A index into two components: one in phase with and proportional to the sunspot number, the other component is then the remaining signal. This remaining signal faithfully represents the sunspot numbers several years in advance. The maximum in this signal occurs near sunspot minimum and is proportional to the sunspot number during the following maximum. This method does allow for a prediction of the next sunspot maximum at the time of sunspot minimum.

A third method is due to Richard Thompson [Solar Physics 148, 383 (1993)]. He found a relationship between the number of days during a sunspot cycle in which the geomagnetic field was "disturbed" and the amplitude of the next sunspot maximum. His method has the advantage of giving a prediction for the size of the next sunspot maximum well before sunspot minimum.
From: http://solarscience.msfc.nasa.gov/predict.shtml 8 December 2009

Sunspot Plotter
Here is a web page where you can go to a specific date and get sunspot data to compare reception conditions with the Solar conditions at the time.
http://spaceweather.com/glossary/sunspotplotter.htm

Thanks to Mike Terry and Ken Fletcher for regular updates

Propagation December '09

2010-01-01T18:27:00.002Z

No report published due to BDXC Transmissions In English.

November '09

2009-10-25T01:12:00.004+01:00

Propagation Forecast
Sunspot activity has once again died down, apart from a minor sunspot on 20 October which has made little difference to the calm conditions which will remain until at least mid November. The Solar Flux will remain at a maximum of 72, and is likely to drop as low as 69, returning to 72 by the 15th. The Boulder A and K indicies will also remain at a steady 5 and 2 repectively during early November. Following speculation new sunspot activity, there has not been any major sunspot activity so far. (From http://www.wm7d.net/hamradio/solar/27d_forecast.shtml )

On 24 October, the NOAA 45 day forecast predicts nothing significant, even up to early December 09: ( www.swpc.noaa.gov/ftpdir/forecasts/45DF/102345DF.txt ) Most long term estimates show a steady rise in sunspot activity which peaks in late 2012 but the actual smoothed sunspot estimates show current figures to be lower than estimated. (http://solarcycle24.com/ )

The Boulder K Index seems to be the best indicator of HF reception conditions. A reading of 3 or under usually indicates calm conditions but 5 or over usually means a noticeable disturbance on the bands.
( http://www.swpc.noaa.gov/alerts/k-index.html )

The K7RA Update
“A tiny Solar Cycle 24 sunspot group -- numbered 1028 -- emerged briefly on Tuesday, October 20, and then was gone. This is another brief phantom sunspot, teasing us with hints of the expected increase in activity that never seems to manifest. Of course, the silver lining in the low solar activity is low geomagnetic activity. While folks in Alaska miss dramatic aurora, HF hams in the northern latitudes can enjoy the bands without all the disruption that comes with geomagnetic storms.

Sunspot numbers for October 15-21 were 0, 0, 0, 0, 0, 11 and 0 with a mean of 1.6. The 10.7 cm flux was 70.4, 69.6, 70.7, 70.1, 70.9, 71 and 71.3 with a mean of 70.6. The estimated planetary A indices were 4, 4, 2, 1, 1, 1 and 1 with a mean of 2. The estimated mid-latitude A indices were 3, 3, 0, 0, 1, 0 and 1 with a mean of 1.1. Franta Janda, OK1HH, of the Czech Propagation Interest Group expects a bit higher activity, with quiet conditions for October 23 and unsettled to active geomagnetic conditions for October 24-25.

A couple of coronal holes are spewing enough plasma to activate some aurora, but remember that most of the photos you see of beautiful displays in the sky are actually very long exposures taken from a rock-steady tripod mount; many times, the unaided eye cannot perceive the more dramatic details. As a result of solar wind from coronal holes, geomagnetic indices rose yesterday, on Thursday, with planetary A index at 14, mid-latitude A index as measured in Virginia at 12 and the College A index at Fairbanks, Alaska way up to 25.

The College A index has been quiet for a long time; the last time the index was nearly this high was on August 30, 2009 at 24. Prior College A index readings higher than Thursday's were July 22, 2009 at 27, February 4, 2009 at 36, December 6, 2008 at 26 and November 8, 2008 at 30.”
(From Tad Cooke: http://www.arrl.org/news/stories/2009/10/23/11162/?nc=1 )

Forecast Of Next Sunspot Cycle
In 2006, scientists predicted that the next cycle, known as Cycle 24, will produce sunspots across an area slightly larger than 2.5 percent of the visible surface of the Sun. The cycle is projected to reach its peak about 2012, one year later than indicated by alternative forecasting methods that rely on statistics.
By analyzing recent solar cycles, the scientists also hope to forecast sunspot activity two solar cycles, or 22 years, into the future. The researchers expect that predicting the Sun's cycles years in advance will lead to more accurate plans for solar storms, which can slow satellite orbits, disrupt communications, and bring down power systems. The team has verified the information by using the relatively new technique of helioseismology, based in part on observations from NASA instruments. This technique tracks sound waves reverberating inside the Sun to reveal details about the interior, much as a doctor might use ultrasound to see inside a patient.
The programme’s director, Paul Bellaire said, "Important discoveries are being made using helioseismology. Through this technique, we can image even the far side of the Sun."
Links to this months articles can be found at http://www.jameswelsh.org.uk/.

Thanks to Ken Fletcher and Mike Terry for updates during 2009. The next Propagation report will be in January 2010.

October '09

2009-09-26T00:58:00.006+01:00

Propagation Forecast
There has actually been some noticeable sunspot activity during September with the Solar flux climbing from the usual 72 to 77, on the 26th where it will remain until 5th October, when it will actually drop down to 69, followed by another rise to at least 74 by the 19th October. If this 20 day trend continues, we should see another peak by early November. The Boulder A index has remained at a steady 5 but has suddenly peaked at 12 on 26 September but settled back to 5 by the 12th. The Boulder K index has remained at 2 but also peaked at 4 on 26th September and again settled back to the ‘norm’ of 2 by the end of September. (WM7d.net). According to the solar charts at http://www.solarcycle24.com the average sunspot numbers will continue to remain at ‘floor level’ during the first quarter of 2010. HF signal path propagation tables can be found at: http://hfradio.org/fot_7.html

Solar Weather Predictions
The NW7US Space Weather\Propagation Podcast. No sunspots by 2015?
In this episode, Amateur Radio Operator, Tomas David Hood (NW7US) discusses with Dr. Penn of the National Solar Observatory the startling yet convincing trend revealed in research of magnetic strengths of sunspots over the last thirteen years. The trend indicates a strong possibility, if the trend continues, that sunspots will disappear by the year 2015! Click Here. You can also access previous podcasts at: http://podcast.hfradio.org/ .

“In 2012, The Sun will be approaching the peak of its 11-year cycle, called "solar maximum", so we can expect a lot of solar activity. Some predictions put the solar maximum of Solar Cycle 24 even more energetic than the last solar maximum in 2002-2003 (remember all those record breaking X-class flares?). Solar physicists are already getting excited about this next cycle and new prediction methods are being put to good use.
An earth-damaging solar flare is very attractive to the doomsayers out there, but let's have a look at what really happens during an Earth-directed solar flare event. The Earth is actually very well protected, although some satellites may not be.
The Earth has evolved in a highly radioactive environment. The Sun constantly fires high-energy particles from its magnetically dominated surface as the solar wind. During solar maximum (when the Sun is at its most active), the Earth may be unlucky enough to be staring down the barrel of an explosion with the energy of 100 billion Hiroshima-sized atomic bombs. This explosion is known as a solar flare and the effects of which can cause problems here on earth.”
(From: http://www.universetoday.com/2008/06/21/2012-no-killer-solar-flare/ )

There is another website by Patrick Geryl which forecasts a disastrous solar storm in 2012! http://www.howtosurvive2012.com

Solar Data Used To Forecast Weather on Earth
Terrestrial weather forecasts using Solar Data are now available on the internet. The technique uses predictable aspects of solar activity - particle and magnetic effects from the Sun - as the basis for forecasting weather many months and even years in advance. Weather Action long-range forecasts are produced using Piers Corbyn's Solar Weather Technique which he says is “the most advanced and reliable long-range forecasting system in the world.” Forecasts can be downloaded for a fee but previous forecasts are available in their archive at: http://www.weatheraction.com

September '09

2009-08-21T17:25:00.003+01:00

Propagation Forecast
At this time, the sun has been blank of official sunspots for over 41 days (www.solarcycle24.com)
The calm Solar Terrestrial conditions are likely to continue for the foreseeable future. According to the NOAA 27 day forecast, the Solar Flux will remain at 68 and the Boulder A index will remain mostly at 5, apart from some minor fluctuations between 2-6 September . The Boulder K Index will remain at 2 except on 2nd and 5th September, which should be only a minor variation of not more than 1 point, so Solar Cycle 24 is not making its presence known so far.
(From: http://www.wm7d.net/hamradio/solar/27d_forecast.shtml )

Solar cycle 24 Predictions.
The progressive Sunspot Number prediction chart on the Solar Cycle 24 website appears to be the most accurate long term forecast predicting the next peak to be in 2013: http://www.solarcycle24.com/sunspots.htm
This prediction has recently been amended: “Radio and Space Services has made a significant change to its forecast for solar cycle 24. The forecast cycle maximum smoothed sunspot number has been dropped from 134 to approximately 90. In addition the time of maximum has been shifted away by one year to September/October 2013. These changes were made due to the protracted solar minimum currently being experienced and the apparent statistical relationship between long solar minimums and lower following solar cycle’s maxima”. (Andy Sennit, Media Network 31 July 2009 via Mike Terry)
See also the Space Weather Prediction Centre: http://www.swpc.noaa.gov/

Optimum Working Frequency Charts. The Western Europe charts can be viewed at: http://hfradio.org/fot_7.html where you can cross reference the time and frequency with the path and it gives you a percentage. These should be accurate for 80% of the month depending on conditions. Links to other regions are included.

Predicting Space Weather (NASA Article: The Key to Understanding The Sun) “A better understanding of the Sun's magnetic field and its behaviour will allow us to make better predictions of space weather. Observations of magnetic fields associated with solar flares show that flares are likely to occur when the magnetic field lines linking two sunspots become sheared or twisted. Observations of the Sun's magnetic field over the last 20 years illustrates its behaviour over two sunspot cycles. However, predicting long-range behaviour, such as the size of the sunspot cycle, is still based on observing trends and patterns. We hope that in the near future we will understand the Sun well enough to make these predictions based on current conditions and past history using a mathematical model of the actual processes.”

Solar Magnetic Fields. “Magnetism is the key to understanding the Sun. Magnetism, or magnetic field, is produced on the Sun by the flow of electrically charged ions and electrons. Sunspots are places where very intense magnetic lines of force break through the Sun's surface. The sunspot cycle results from the recycling of magnetic fields by the flow of material in the interior. The prominences seen floating above the surface of the Sun are supported, and threaded through, with magnetic fields. The streamers and loops seen in the corona are shaped by magnetic fields. Magnetic fields are at the root of virtually all of the features we see on and above the Sun. Without magnetic fields the Sun would be a rather boring star”.

Measuring Magnetic Fields. “Magnetic forces change the direction of motion of moving charged particles like electrons. Because of this, electrons that orbit around a nucleus in one direction will have more energy than electrons that orbit about the nucleus in the opposite direction. This allows us to remotely measure the Sun's magnetic field by observing the difference in the energy of the light emitted as these electrons jump from orbit to orbit. With the proper instrumentation we can determine both the strength and the direction of the magnetic field all across the surface of the Sun.” ”. (More on this subject at: http://solarscience.msfc.nasa.gov/the_key.shtml )

Thanks also to Ken Fletcher and Mike Terry. Links can be found at http://www.jameswelsh.org.uk

August '09

2009-07-23T02:51:00.008+01:00

Solar Conditions

The mostly calm propagation conditions will continue and the only minor variations will be August 6-10 when the Boulder 'A' index will peak at 8. Things will then settle down to the recent 'norm' of A=5 and K=2. The Solar Flux should also remain between 68 and 70 during this period.

We saw a run of eight days with a large sunspot during July, but none have emerged since. Unlike other recent spots, this one did not appear just for one or two days and then vanish. Sunspot numbers for July 9-15 were 15, 13, 0, 0, 0, 0 and 0 with a mean of 4. The Solar flux was 69.1, 67.8, 68.2, 68, 67.2, 66.6 and 66.5 with a mean of 67.6. The estimated planetary A indices were 6, 7, 4, 5, 10, 8 and 5 with a mean of 6.4. The estimated mid-latitude A indices were 6, 7, 2, 4, 5, 6 and 3 with a mean of 4.7.

Previous Solar Cycles

Solar Cycle 23 began in October 1996, so Solar Cycle 24 should have had an impact on Solar conditions by now, as Solar cycles typically last 11 years, but the ‘false alarms’ continue as we see the occasional burst of Solar activity followed by yet another period of ‘Quiet to Unsettled’. In October 1991, Solar Cycle 22 reached its peak in a short period, but Solar Cycles 17, 20 and 23 were very similar to each other. Here is another website which has both text and graphical charts which show this quite clearly: http://www.solen.info/solar/

The WM7d forecast is easy to understand as it gets to the point without going through too much detailed data: http://www.wm7d.net/hamradio/solar/27d_forecast.shtml

A 45 day text based forecast can be found at: http://www.swpc.noaa.gov/ftpmenu/forecasts/45DF.html

Here is yet another site dedicated to HF propagation conditions: http://dx.qsl.net/propagation/

Sunspot Numbers:
Observers around the world compute daily sunspot numbers by multiplying the number of observed sunspot groups by ten and then adding this product to his total count of individual spots. Results vary greatly, since the measurement strongly depends on observer interpretation and experience and on the stability of the Earth's atmosphere above the observing site.
Moreover, the use of Earth as a platform from which to record these numbers contributes to their variability, too, because the sun rotates and the evolving spot groups are distributed unevenly across solar longitudes.
To compensate for these limitations, each daily international number is computed as a weighted average of measurements made from a network of cooperating observatories. Sunspot counts rise and fall approximately every 11.1 years. The cycle, though, is not symmetrical, for the spot count takes on the average about 4.8 years to rise from a minimum to a maximum and another 6.2 years to fall to a minimum once again. The largest annual mean number (190.2) occurred in 1957.
There is a comprehensive FAQ’s page about Sunspot numbers and Space Weather in general at: http://www.space.com/spacewatch/solar_faq.html#g1

ASAP Software
Bradford University have a software download called ASAP (Automated Solar Activity Prediction) which shows real time Solar data on your PC, although I haven’t tried it yet. Details at: http://spaceweather.inf.brad.ac.uk/asap.html

Thanks to Mike Terry and Ken Fletcher for regular updates.

July '09

2009-06-19T02:17:00.004+01:00

Propagation Forecast
The Boulder A, and K indices will remain at their ‘norm’ of 5 and 2 until the end of June when there will be a disturbance on the 30th with the ‘A’ at 5 and the ‘K’ at 3. Things should return to normal by 2nd July with the A and the K back to 5 and 2 respectively. The Solar Flux however, will go from 68 to 70 around 26 June, dropping back to 68 by July 10th.

Mystery of the Missing Sunspots, Solved?
The sun is in the pits of a century-class solar minimum, and sunspots have been puzzlingly scarce for more than two years. Now, for the first time, solar physicists might understand why.
At an American Astronomical Society press conference in Boulder, Colorado, researchers announced that a jet stream deep inside the sun is migrating slower than usual through the star's interior, giving rise to the current lack of sunspots. Rachel Howe and Frank Hill of the National Solar Observatory (NSO) in Tucson, Arizona, used a technique called Helioseismology to detect and track the jet stream down to depths of 7,000 km below the surface of the sun. The sun generates new jet streams near its poles every 11 years, they explained to a room full of reporters and fellow scientists. The streams migrate slowly from the poles to the equator and when a jet stream reaches the critical latitude of 22 degrees, new-cycle sunspots begin to appear. Howe and Hill found that the stream associated with the next solar cycle has moved sluggishly, taking three years to cover a 10 degree range in latitude compared to only two years for the previous solar cycle. The jet stream is now, finally, reaching the critical latitude, heralding a return of solar activity in the months and years ahead.
"It is exciting to see", says Hill, "that just as this sluggish stream reaches the usual active latitude of 22 degrees, a year late. We finally begin to see new groups of sunspots emerging." The current solar minimum has been so long and deep, some scientists speculated that the sun might enter a long period with no sunspot activity at all, akin to the Maunder Minimum of the 17th century. This new result dispels those concerns. The sun's internal magnetic dynamo is still operating, and the sunspot cycle is not "broken." (NASA Science News 17 June 2009)

CQ Magazine Propagation editor challenges Solar cycle 24 Predictions
CQ magazine's Propagation Editor is challenging the accuracy of the newest predictions on Solar Cycle 24. The revised prediction, issued in late May by a panel of solar experts, suggests a weak sunspot cycle with a peak in 2013. But CQ Propagation Editor Tomas Hood, NW7US, is asking "How Credible Are These 'Experts'?"
In an online commentary posted on the CQ magazine website, Hood notes that this same group of so-called "experts" has issued multiple predictions for this cycle already, all of which they now say are wrong, and asks why we should believe they're right this time.
Hood points out that, while the Sun itself is millions of years old, scientists have been tracking solar activity for just a few hundred years. "In my view," he says, "it is pretty arrogant to postulate that mankind has any real understanding and handle on what the Sun might do next. If none of the models are totally correct, how are they making this current prediction with such dismal expectations? I'm not holding my breath in favour of supporting any of the predictions at this point." He also points out that there are already signs of "an awakening Solar Cycle 24," and encourages hams to "enjoy the unique propagation opportunities currently presenting themselves during this quiet phase," and to "prepare now for whatever the sun will do by honing your radio skills."
( http://www.cq-amateur-radio.com Via Southgate ARC http://www.southgatearc.org and Mike Terry)

HUF, MUF and LUF Charts
Ken Fletcher sent me a link to some useful charts of the Highest, Medium and Lowest useable frequency charts which can be downloaded from the ARRL website in PDF format. These regional charts are based on average readings for June ’09, and some may remember similar charts being published in Wireless World. http://www.arrl.org/qst/propcharts/2009/06/East-Coast.pdf. Charts can also be found at: http://www.dxzone.com/catalog/Propagation/

Links to these articles can be found at: www.jameswelsh.org.uk

Propagation June '09

2009-05-22T14:25:00.003+01:00

Propagation Forecast
The Boulder 'A' index has remained at a steady 5 and the K index at 2. The first half of June will see 2 fluctuations in these figures. The first one being June 1 – 4 with the A index peaking at 10 and the K index at 4 on June 4th, and again 10th June with the A index peaking at 8 and the K index at 3. The Solar Flux is also starting to vary. June will start out at 70 but this will rise to 72 by Jun 4th and to 74 by the 8th, where it will remain until at least June 13th.

Solar Cycle 24 Prediction Update: Solar Minimum Was December 2008
The Solar Cycle 24 Prediction Panel has reached a consensus decision on the prediction of the next solar cycle (Cycle 24). First, the panel has agreed that solar minimum occurred in December, 2008. This still qualifies as a prediction since the smoothed sunspot number is only valid through September, 2008. The panel has decided that the next solar cycle will be below average in intensity, with a maximum sunspot number of 90. Given the predicted date of solar minimum and the predicted maximum intensity, solar maximum is now expected to occur in May, 2013. Note, this is a consensus opinion, not a unanimous decision. A supermajority of the panel did agree to this prediction. See: http://www.swpc.noaa.gov/SolarCycle/SC24/

This contradicts a report in March 2006 when Dr David Hathaway of the National Space Science and Technology Centre (NSSTC) announced that solar minimum had already arrived and that Solar Maximum would peak in 2010-2011 and would be 30% to 50% stronger than the historic solar maximum of 1958.

In 2006, researchers announced that the most intense storm in 50 years was coming. The prediction came from a team led by Mausamu Dikpati of the National Centre for Atmospheric Research (NCAR). The next sunspot cycle was predicted to be 30% to 50% stronger than the historic solar max of 1958.
From: http://www.nasa.gov/vision/universe/solarsystem/10mar_stormwarning.html

The 1958 Solar Maximum
In 1958 satellites were in their infancy with the Russian Sputnik being launched in October and also Explorer 1, the first US satellite was launched that year. Even so, people knew something was happening when the Northern Lights were sighted 3 times over Mexico. If a similar maximum happened today, it would be noticed by its effect on mobile phones, weather satellites and possibly domestic TV satellites.

The Conveyor Belt Effect
Dr David Hathaway of the NSSTC also has a theory about the ‘Conveyor Belt’ effect which is caused by revolving magnetic fields which carry sunspots away from the sun and back again when they lose their energy.
When the belt is turning "fast," it means that lots of magnetic fields are being swept up, and that a future sunspot cycle is going to be intense. This is a basis for forecasting: "The belt was turning fast in 1986-1996," says Hathaway. "Old magnetic fields swept up then should re-appear as big sunspots. All this happens with massive slowness and a loop can last between 30 and 50 years, so predictability is still variable. Pictures at: http://www.nasa.gov/vision/universe/solarsystem/10mar_stormwarning.html
Historical Solar data Charts Solar charts from 1954 to 2006 from the World Data Centre are available at http://www.solen.info/solar/history/

Thanks to Mike Terry and Ken Fletcher for regular updates. Links to these articles can be found at www.jameswelsh.org.uk

May '09

2009-04-24T00:58:00.003+01:00

Propagation Forecast
April has been fairly constant with the A index mostly at 5 and the K index mainly at 2. These conditions are likely to continue in May except for a fluctuation on the 6th, with the A index peaking at 15 and the K index at 4. This should drop back to the norm of A5 and K2 by 11 May. The Solar Flux should remain at a steady 70 during this period.

Deep Solar Minimum. The sunspot cycle is behaving a little like the stock market. Just when you think it has hit bottom, it goes even lower. 2008 was a bear. There were no sunspots observed on 266 of the year's 366 days (73%). To find a year with more blank suns, you have to go all the way back to 1913, which had 311 spotless days. Prompted by these numbers, some observers suggested that the solar cycle had hit bottom in 2008. Maybe not. Sunspot counts for 2009 have dropped even lower. As of March 31st, there were no sunspots on 78 of the year's 90 days (87%).
It adds up to one inescapable conclusion: "We're experiencing a very deep solar minimum," says solar physicist Dean Pesnell of the Goddard Space Flight Centre.
"This is the quietest sun we've seen in almost a century," agrees sunspot expert David Hathaway of the Marshall Space Flight Centre. Quiet suns come along every 11 years or so. It's a natural part of the sunspot cycle, discovered by German astronomer Heinrich Schwabe in the mid-1800s. Sunspots are planet-sized islands of magnetism on the surface of the sun; they are sources of solar flares, coronal mass ejections and intense UV radiation. Plotting sunspot counts, Schwabe saw that peaks of solar activity were always followed by valleys of relative calm—a clockwork pattern that has held true for more than 200 years. The current solar minimum is part of that pattern. In fact, it's right on time. "We're due for a bit of quiet—and here it is," says Pesnell.
But is it supposed to be this quiet? In 2008, the sun set the following records:
A 50-year low in solar wind pressure: Measurements by the Ulysses spacecraft reveal a 20% drop in solar wind pressure since the mid-1990s—the lowest point since such measurements began in the 1960s. The solar wind helps keep galactic cosmic rays out of the inner solar system. With the solar wind flagging, more cosmic rays are permitted to enter, resulting in increased health hazards for astronauts. Weaker solar wind also means fewer geomagnetic storms and auroras on Earth.

A 12-year low in solar "irradiance": Careful measurements by several NASA spacecraft show that the sun's brightness has dropped by 0.02% at visible wavelengths and 6% at extreme UV wavelengths since the solar minimum of 1996. The changes so far are not enough to reverse the course of global warming, but there are some other significant side-effects: Earth's upper atmosphere is heated less by the sun and it is therefore less "puffed up." Satellites in low Earth orbit experience less atmospheric drag, extending their operational lifetimes. Unfortunately, space junk also remains longer in Earth orbit, increasing hazards to spacecraft and satellites.

A 55-year low in solar radio emissions: After World War II, astronomers began keeping records of the sun's brightness at radio wavelengths. Records of 10.7 cm flux extend back all the way to the early 1950s. Radio telescopes are now recording the dimmest "radio sun" since 1955. Some researchers believe that the lessening of radio emissions is an indication of weakness in the sun's global magnetic field. No one is certain, however, because the source of these long-monitored radio emissions is not fully understood. (NASA Science News 1 April 2009)

NASA Discuss The Anatomy Of Solar Storms NASA held a Science Update on April 14, to present new findings and three-dimensional views revealing the inner workings of solar storms known as coronal mass ejections. The data will improve the ability to predict how and when these solar tsunamis impact Earth, affecting communication systems, power grids, and other technology. It is available on NASA TV at: http://www.nasa.gov/multimedia/nasatv/ Acknowledgements to Ken Fletcher and Mike Terry
Links to these articles and more can be found at: www.jameswelsh.org.uk

April '09

2009-03-28T04:14:00.005Z

Propagation Forecast
During the second half of March, conditions have remained quite steady with the A index mostly at 5 and the K index at 2. As we enter the A09 period, things are likely to remain the same during April except for the 9th with the A index at 15 and the k index at 4. This should return to normal by April 11th. The Solar flux is likely to remain at a steady 70 during this period.
(From: http://www.wm7d.net/hamradio/solar/27d_forecast.shtml)

Modes of propagation
Here is an interesting article explaining modes of radio propagation and how they work:
The three main modes of propagation of electromagnetic waves are:
(a) Ground (or surface) Wave
(b) Ionosphere Wave (Sky Wave)
(c) Tropospheric Wave

Ground-Wave Propagation In ground-wave propagation, the radiated wave follows the surface of the earth. It is the major mode of propagation for frequencies up to about 2MHz. Attenuation of the ground wave increases very rapidly above 2MHz and it may extend for only a few kilometers at frequencies of the order of 15- 20MHz. At very low frequencies the attenuation decreases to such an extent that reliable world-wide communication is possible at all times. The ground wave is not so affected by atmospheric effects or time of day as other modes, particularly at frequencies below about 500 kHz.

Ionospheric Propagation Ionospheric propagation is the 'refraction' (i.e. bending), and hence reflection, of radio waves back to earth by layers of ionised gases as shown in Fig 7.2. It is the normal mode of propagation over the frequency range of about 1MHz to 30MHz.
These layers are the F2 layer (height 300-400km); Fl layer (about 200km) and the E layer (about 120km). At night and in midwinter, the F1 and F2 layers tend to combine into a single layer at a height of about 250km. At about 80km there is a much less distinct layer which is generally known as the D region.
The ionised layers are the result of the ionisation of the oxygen, nitrogen and nitric oxide in the rarefied atmosphere at these heights by X-Ray and ultra-violet radiation of various wavelengths which comes from the sun.
When these gases are ionised the molecules split up into ions and free electrons, and recombine after sunset. This whole region is therefore known as the 'ionosphere'.
The solar radiation which causes the ionisation is continually varying; hence the degree of ionisation varies considerably according to season and time of day. It has also been found that the degree of ionisation is affected by the number of sunspots.
(You can read the full article at: http://www.ukradioamateur.co.uk/full/html/c7-1-2.htm)

NOAA Space Weather Prediction Centre Here is a web page featuring the latest solar weather indices including real time maps, solar wind dials and a solar cycle progression chart: http://www.swpc.noaa.gov/SWN/index.html

Thanks to Mike Terry and Ken Fletcher for updates. Links to the above articles can be found at. http://www.jameswelsh.org.uk

March'09

2009-02-28T02:38:00.005Z

Propagation Forecast

During the second half of February, conditions have remained much the same with the A index at 5 and the K index at 2. This is set to continue into March, except for the 13th , when the A index will peak at 12 and the K index will reach 4. The 14th March will be much the same with the A index down to 10 and the K down to 3. Conditions will settle beck to ‘normal’ by the 15th with the A and K indices returning to 5 and 2 respectively. The Solar flux, however is forecast to stay at a steady 70 throughout this period.
(Data from: http://www.wm7d.net/hamradio/solar/27d_forecast.shtml )

Solar Cycle 24 Update
Looking at the Sunspot trend charts on Solarcycle24.com, it seems we will not see any significant difference in HF conditions until early 2010 when sunspot activity is forecast to rise steadily until the end of 2012. This will steadily drop down towards another low period by around 2020. Detailed charts can be found at: http://solarcycle24.com/flares.htm

Online Popagation Primer
Here is an interesting website featuring Flash Media videos about how HF propagation works, which is divided into sections including The Sun, The Ionosphere and the indices, explaining how to understand the A index, the K index and the Solar Flux. You will require a Broadband connection to view these files
http://www.ae4rv.com/tn/propflash.htm See also this website explaining how shortwave propagation actually works: http://dzabcik.home.texas.net/propagation.html See also Propagation Noise and Effectiveness at: http://hfradio.org/ace-hf/ace-hf-noise.html

AM Noise Sources“The radio noise problem is as old as radio itself. Unfortunately it is getting worse as technology steadily progresses and more man-made electronic products hit the shelves. This is a direct result of mainly consumer products that generate an increasingly higher noise level. The technology behind the AM broadcast signal is very out-dated as far as current technology is concerned, not to mention that the AM broadcast band is located in the very vulnerable medium wave frequency band.”
This is an article from radiolabs.com which details the amount of devices which can cause noise on the AM bands. This article can be found at: http://www.radiolabs.com/Articles/amnoise.html

Localised Radio Interference
The number of videos on YouTube showing the interference that 'Homeplug' type devices cause to peoples' enjoyment of radio listening continues to grow. A selection of Youtube postings can be found at: http://www.southgatearc.org/news/february2009/new_plt_interference_videos.htm

There is also the UKQRM group at: http://www.ukqrm.org/ There are many features on this site including a page for identifying different sources of interference from power line adapters to electric fences: http://www.mikeandsniffy.co.uk/UKQRM/database.htm For the latest updates, you can also join their Yahoo Group at: http://tech.groups.yahoo.com/group/UKQRM/
(From Mike Terry 9 February 2009)

Links to these articles and more can be found at: http://www.jameswelsh.org.uk

February '09

2009-01-24T05:34:00.003Z

Propagation Forecast
Conditions in January have remained quiet with the A index at 5 and the K index at 2. However, January will end with a disturbance on the 27th, with 'A' index peaking at 5 and the 'K' Index at 3. The 29th should be calm followed by a lesser disturbance on the 30th, then the calm conditions will then remain until at least February 14th. From: http://www.wm7d.net/hamradio/solar/27d_forecast.shtml

Severe Space Weather.
Severe Geomagnetic Storms can affect other things besides radio reception, according to a recent report in NASA Science News. The problem begins with the electric power grid. "Electric power is modern society's cornerstone technology on which virtually all other infrastructures and services depend," the report notes. Yet it is particularly vulnerable to bad space weather. Ground currents induced during geomagnetic storms can actually melt the copper windings of transformers at the heart of many power distribution systems. Sprawling power lines act like antennas, picking up the currents and spreading the problem over a wide area. The most famous geomagnetic power outage happened during a space storm in March 1989 when six million people in Quebec lost power for 9 hours. To estimate the scale of such a failure, report co-author John Kappenmann of the Metatech Corporation looked at the great geomagnetic storm of May 1921, which produced ground currents as much as ten times stronger than the 1989 Quebec storm, and modeled its effect on the modern power grid. He found more than 350 transformers at risk of permanent damage and 130 million people without power. The loss of electricity would ripple across the social infrastructure with "water distribution affected within several hours; perishable foods and medications lost in 12-24 hours; loss of heating/air conditioning, sewage disposal, phone service, fuel re-supply and so on. Read the full article at: http://science.nasa.gov/headlines/y2009/21jan_severespaceweather.htm

NASA'S Mission to Improve Predictions of Violent Space Weather
Sometime between the end of 2008 and the beginning 2009, NASA will launch the Solar Dynamics Observatory (SDO) to trace Solar disturbances back to their origin deep within the sun. SDO will discover how the sun builds up and explosively releases magnetic energy, which powers severe space weather.
"Right now, we can make limited space weather predictions, but they are baby steps compared to our ability to forecast weather on Earth," said Dr. Dean Pesnell of NASA's Goddard Space Flight Centre, Greenbelt, Md., Project Scientist for SDO. "SDO's instruments are designed to work together to tell us more about how solar storms form, which will improve predictions of when they are about to happen."
Heat from nuclear fusion in the sun's core makes its outer layer churn like a pot of boiling water. Solar storms are born deep in this outer layer, with tangled magnetic fields generated by the sun’s churning electrically conducting gas (plasma). Like a rubber band that has been twisted too far, solar magnetic fields can suddenly snap to a new shape, releasing tremendous energy as a solar flare or a coronal mass ejection (CME).
Solar flares are explosions in the sun’s atmosphere, with the largest equal to billions of one-megaton nuclear bombs. Solar magnetic energy can also blast billions of tons of plasma into space at millions of miles (kilometres) per hour as a CME. This violent solar activity often occurs near sunspots, dark regions on the sun caused by concentrated magnetic fields. Sunspots and stormy solar weather follow a cycle that repeats approximately every eleven years, from few sunspots and quiet conditions to many sunspots and active, and back again.
The key to predicting solar storms and the solar activity cycle is an understanding of the flows of plasma inside the sun. Magnetic fields are "frozen" into the solar plasma, so plasma currents within the sun transport, concentrate, and help dissipate solar magnetic fields. Currently, the Sun’s activity is at its minimum, but by the time of the SDO launch, the activity level is expected to rise significantly.
Although the general process of solar activity and its cyclic behaviour are known, many of the details are not, such as exactly what magnetic structures lead to flares and CMEs. These details need to be discovered before solar storm predictions improve, and SDO's suite of three instruments is designed to do just that. ( From: http://www.physorg.com/news123774611.html )
Thanks to Mike Terry and Ken Fletcher for regular updates.

January 2009

2009-01-03T14:46:00.001Z

Propagation Forecast

Sunspot numbers have progressively dropped so far this century when they started of at around the 120 mark. The end of 2008 has seen al all time low so far this century of 2. Boulder forecast charts estimate a steady yearly increase to around 80 by the second half of 2013. (www.solarcycle24.com)

Solar flux has virtually remained at a steady 70 during December and is forecast to remain the same until the end of January. The Boulder A Index peaked at 12 on 2nd January where it will remain until the end of the month. The Boulder K index, after starting in January at 4, will remain at 2 from the 4th January onwards. This will mean steady conditions throughout the rest of January.

First Meteors Of 2009
The annual Quadrantid meteor shower peaked on Jan. 3rd when Earth entered a stream of debris from shattered comet 2003 EH1. The timing of the encounter favored observers in Western North America and across the Pacific Ocean who could see dozens to hundreds of meteors during the dark hours before sunrise this Saturday morning. Visit http://spaceweather.com for a sky map and more information.

Space Weather Radio
For the new year, Spaceweather.com is pleased to announce a new service: Space Weather Radio, broadcasting live "sounds from space" around the clock. Today you can listen to the Air Force Space Surveillance Radar in Texas. When a meteor passes over the facility--ping!--there is an audible echo. (Activity should be high during the Quadrantid meteor showers) In the near future we'll be adding broadcasts of solar radio bursts and VLF signals from the ionosphere. The streams are punctuated by Daily Space Weather Updates .

2008. Blankest Year Of The Space Age
Astronomers who count sunspots have announced that 2008 is now the "blankest year" of the Space Age. As of Sept. 27, 2008, the sun had been blank, i.e., had no visible sunspots, on 200 days of the year. To find a year with more blank suns, you have to go back to 1954, three years before the launch of Sputnik, when the sun was blank 241 times.
"Sunspot counts are at a 50-year low," says solar physicist David Hathaway of the NASA Marshall Space Flight Center. "We're experiencing a deep minimum of the solar cycle." (www.nasa.gov)

“The sun is behaving normally”. So says NASA solar physicist David Hathaway. "There have been some reports lately that Solar Minimum is lasting longer than it should. That's not true. The ongoing lull in sunspot number is well within historic norms for the solar cycle."
This report, that there's nothing to report, is newsworthy because of a growing buzz in lay and academic circles that something is wrong with the sun. Sun Goes Longer Than Normal Without Producing Sunspots declared one recent press release. A careful look at the data, however, suggests otherwise. But first, a status report: "The sun is now near the low point of its 11-year activity cycle," says Hathaway. "We call this 'Solar Minimum.' It is the period of quiet that separates one Solar Max from another."
During Solar Max, huge sunspots and intense solar flares are a daily occurrence. Auroras appear in Florida. Radiation storms knock out satellites. Radio blackouts frustrate hams. The last such episode took place in the years around 2000-2001.
During Solar Minimum, the opposite occurs. Solar flares are almost nonexistent while whole weeks go by without a single, tiny sunspot to break the monotony of the blank sun. This is what we are experiencing now.
Hathaway has studied international sunspot counts stretching all the way back to 1749 and he offers these statistics: "The average period of a solar cycle is 131 months with a standard deviation of 14 months. Decaying solar cycle 23 (the one we are experiencing now) has so far lasted 142 months--well within the first standard deviation and thus not at all abnormal. The last available 13-month smoothed sunspot number was 5.70. This is bigger than 12 of the last 23 solar minimum values."
In summary, "the current minimum is not abnormally low or long." (Nasa.gov)

Thanks to Mike Terry and Ken Fletcher for regular updates

November '08

2008-10-24T19:33:00.004+01:00

Propagation Forecast
The last week in October will have been quiet with the 'A' index at 5 and the ‘K’ at 2, but there will be a disturbance peaking on the 30th with the ‘A’ index at 15 and the ‘K’ at 4. The next major disturbance will peak on November 7th with the 'A' index again at 15 and the ‘K’ at 4. This should settle back to normal by the 10th. The Solar Flux however should remain at 68, rising to 70 by the 4th November then dropping to 69 by the 13th. (www.wm7d.net)

“New Cycle” Sunspot
On 19th October, a "new-cycle" sunspot belonging to Solar Cycle 24 was emerging near the sun's north-eastern limb. This was the third time in as many weeks that a new-cycle sunspot has interrupted the year's remarkable run of blank suns.
The accelerating pace of new-cycle sunspot production is an encouraging sign that, while solar activity remains very low, the sunspot cycle is unfolding more or less normally. We are not stuck in a permanent solar minimum.
IRTS Radio News Bulletin 19 October 2008 http://www.irts.ie

Space Weather reports that for the first time in months, a significant sunspot is emerging on the solar disk. Its described as a fast-growing active region with two dark cores, each larger than Earth. The magnetic polarity of the sunspot identifies it as a member of new Sunspot Cycle 24. This is viewed as an encouraging sign that the 11-year solar cycle is indeed progressing, albeit very, very slowly. (www.spaceweather.com)

2008, Blankest Year of the Space Age
Astronomers who count sunspots have announced that 2008 is now the "blankest year" of the Space Age. As of Sept. 27, 2008, the sun had been blank, i.e., had no visible sunspots, on 200 days of the year. To find a year with more blank suns, you have to go back to 1954, three years before the launch of Sputnik, when the sun was blank 241 times.
"Sunspot counts are at a 50-year low," says solar physicist David Hathaway of the NASA Marshall Space Flight Center. "We're experiencing a deep minimum of the solar cycle."

If solar activity continues as low as it has been, 2008 could rack up a whopping 290 spotless days by the end of December, making it a century-level year in terms of spotlessness.
Hathaway cautions that this development may sound more exciting than it actually is: "While the solar minimum of 2008 is shaping up to be the deepest of the Space Age, it is still unremarkable compared to the long and deep solar minima of the late 19th and early 20th centuries." Those earlier minima routinely racked up 200 to 300 spotless days per year. (NASA Science News September 30, 2008)
http://science.nasa.gov/headlines/y2008/30sep_blankyear.htm?list1066509

Jim Linton VK3PC of Wireless Institute Of Australia reports: “The false start announced last year for the new Solar Cycle 24 has been followed up with speculation of things like `double dip' minima and even a new ice age for sunspots. But let's try to stay positive and not subscribe to thoughts of another minimum of 70 years, as occurred from 1645 to 1715, the only flat-lining in sunspot cycles since records.
Looking back at the onset of previous cycles that followed prolonged periods without sunspots, gives indication that Cycle 24 may have a much greater start-up intensity. Should it behave like Cycles 11 to 14 in the 19th century there will be more years rising and a shorter period in decline. The latest prediction is that Cycle 24 will be begin in mid 2009.
The prolonged solar minimum is also occurring at a time of reports in the northern hemisphere of continued sporadic-E enhancement on both the ten and six metre bands.”
Jim Linton, VK3PC. Amatuer Radio Newsline (Wireless Institute Of Australia http://www.wia.org.au/)
Thanks to Mike Terry and Ken Fletcher for regular updates.
Links to these articles and more can be found on my links page: www.jameswelsh.org.uk

October 2008

2008-09-18T18:01:00.002+01:00

Propagation Forecast.
The ‘mill pond’ conditions are likely to continue until the end of September, with the A index at 5 and the K index at 2 which I will refer to as ‘normal’ for this period. October will begin with a disturbance peaking on October 1st with the A Index rising to 30 and the K index to 5. This will have calmed down to ‘normal’ by October 8th and will be followed by a lesser disturbance on 12th October with the A index at 12 and the K Index at at 14, returning to ‘normal’ by the 15th. The Solar flux, however will remain at a constant 67 during this period. From: http://www.wm7d.net/hamradio/solar/27d_forecast.shtml
There is still much speculation among the scientific community about the true beginning of Solar Cycle 24. In 2008, a negatively charged sunspot on January 24 was thought to be the start of the new solar cycle, as was another very weak sunspot on 31 July. The general consensus of opinion is now mid 2009!
Solar cycle 24 “will begin in mid 2009”
The false start announced last year for the new Solar Cycle 24 has been followed up with speculation of things like ‘double dip’ minima and even a new ice age for sunspots. But let’s try to stay positive and not subscribe to thoughts of another minimum of 70 years, as occurred from 1645 to 1715, the only flat-lining in sunspot cycles since records.
Looking back at the onset of previous cycles that followed prolonged periods without Sunspots, gives indication that Cycle 24 may have a much greater start-up intensity. Should it behave like Cycles 11 to 14 in the 19th century there will be more years rising and a shorter period in decline.
The latest prediction is that Cycle 24 will begin in mid 2009. The prolonged solar minimum is also occurring at a time of reports in the Northern Hemisphere of continued sporadic-E enhancement on both the ten and six metre bands.
Greyline propagation on HF also is experiencing a lack of geomagnetic disturbance, which is a good thing. Jim Linton VK3PC. Wireless Institute of Australia http://www.wia.org.au/

A new sunspot, number 1001, emerged on Thursday, September 11. It is actually a single group with two small magnetic disturbances. The previous Sunspot, was a weak one barely emerging on August 21-22. It was so small that some observatories didn't count it, but it was a Cycle 24 spot.
August was much ballyhooed as the first time since 1913 that there was a month or more between the most recent sunspot appearances. Actually it was the first time that a whole calendar month went by with no spots. Of course, this doesn't really mean anything more than any other 30 day period with no spots, because the calendar is based on arbitrary beginnings and endings.
From K7RA via Southgate ARC http://www.southgatearc.org/rss/

See also this article about solar cycle 24 and its implications for the United States by David Archibald at: www.warwickhughes.com/agri/Solar_Arch_NY_Mar2_08.pdf

I also found this article from Ben Carlson writing in The Atlantic magazine:
Will changes in sunspot activity wreak havoc on earth? With the advent of Solar Cycle 24, many scientists expect a massive spike in solar activity that will have the potential to disrupt satellites, cell phones, and air traffic in 2012. But the real concern is Solar Cycle 25. Around 2022, a catastrophic drop in sun activity—the lowest in centuries, according to NASA—may cause temperatures on earth to plunge, inaugurating an extended period of cold. In other words, a new Ice Age.
What seems to have escaped many reporters’ grasps is that this dire scenario doesn’t square with the facts. The only evidence its proponents present is the seeming correlation between the “Little Ice Age” of the 17th and 18th centuries and a concurrent period of solar slump. But as everyone would do well to remember, climate is far more complicated than that. As one of the most chaotic and multi-variable systems humans study, it is easy to see why debates over climate change often occur.
Ben Carlson The Atlantic http://thecurrent.theatlantic.com/archives/2008/02/the-ice-age-cometh.phpThanks to Ken Fletcher and Mike Terry for regular updates.
Links to these articles and more can be found at: www.jameswelsh.org.uk

September 08

2008-08-23T23:38:00.005+01:00

Propagation Forecast
From August 20th, conditions have remained quiet with the A index at 5, and the K index at 2. This is likely to remain the same except for September 5th with the A index at 18 and the K at 4. Also on September 12th, conditions should again become disturbed with the A index peaking at 20 on the 14th and the K index peaking at 5.
The Solar Flux, however has remained at a steady 66 and is likely to remain the same until at least mid September

MUF Map A near-real-time Maximum Usable Frequency map can be found at: http://www.spacew.com/www/realtime.php

Sunspot Numbers For 2008. With the exception of March, monthly average sunspot numbers have been on a downward trend so far during 2008. January started with an average sunspot number of 26 slowly dropping to 12 by the end of July. NOAA Predicted trends for 2008 have been fairly accurate, although sunspot numbers have been generally higher than predicted. Details at: http://www.solarcycle24.com/sunspot.htm

HF Propagation Flash Movie
Here is a website featuring a flash movie which explains how HF radio propagation actually works: http://www.ae4rv.com/tn/propflash.htm .
A 45 day Solar Flux and A index forecast can also be found at: http://www.dxing.info/propagation

The Sun's Magnetic Field
When the transition from Cycle 23 to 24 occurs the magnetic field which surrounds the sun will change it's polarity. This will be apparent in the magnetic stucture of individual sunspot groups as seen in solar magnetograms such as those recorded at the IPS/USAF Learmonth Solar Observatory in Western Australia. With a change in the solar cycle, the polarity of the leader and trailer spots of a sunspot group are reversed. This observation, in conjunction with the latitude at which the new spot formed, will indicate that the change to the new solar cycle is underway. From: http://www.ips.gov.au/Educational

August 08

2008-07-26T03:09:00.002+01:00

Propagation Forecast
Propagation conditions during July have been fairly calm, especially from the 25th with the A index at 5 and the K index at 2. After a slight fluctuation on the 1st August, conditions will remain the same until the 7th when there will be another disturbance which will last until the 14th and will peak on the 8th with the A index at 20 and the K index at 5. Things will then remain calm until the 10th August with the A index rising to 10 and the K index to 3. The worst days will be 7th to the 12th and also the 18th.
The solar flux however will remain at 2 during the first week in August, rising to 5 by the 8th and settling back to 3 by the 18th. (http://www.wm7d.net)
Long distance low and medium frequency (below 2 MHz) propagation along paths north of due west over high and upper middle latitudes is poor. Propagation on long distance northeast-southwest paths is generally poor to fair. (www.dxlc.com)
Solar Cycle 24 Prediction
June 27, 2008 During the annual Space Weather Workshop held in Boulder, CO in May, 2008, the Solar Cycle 24 Prediction Panel released an update to the prediction for the next solar cycle. In short, the update is that the panel has not yet made any changes to the prediction issued in April, 2007. The panel predicted solar minimum to occur in March, 2008. The panel expects the solar cycle to reach a peak sunspot number of 140 in October, 2011 or a peak of 90 in August, 2012.
The 2008 Perseid Meteor Shower 12th August.
"Peaking on August 12th, it should be a good show. "The time to look is during the dark hours before dawn on Tuesday, August 12th," says Bill Cooke of NASA's Meteoroid Environment Office at the Marshall Space Flight Center. "There should be plenty of meteors--perhaps one or two every minute.
The source of the shower is Comet Swift-Tuttle. Although the comet is far away, currently located beyond the orbit of Uranus, a trail of debris from the comet stretches all the way back to Earth.
Crossing the trail in August, Earth will be pelted by specks of comet dust hitting the atmosphere at 132,000 mph. At that speed, even a flimsy speck of dust makes a vivid streak of light when it disintegrates--a meteor! Because, Swift-Tuttle's meteors streak out of the constellation Perseus, they are called "Perseids.
Serious meteor hunters will begin their watch early, on Monday evening, August 11th, around 9 pm when Perseus first rises in the northeast. This is the time to look for Perseid Earthgrazers--meteors that approach from the horizon and skim the atmosphere overhead like a stone skipping across the surface of a pond." (NASA Science News http://science.nasa.gov/headlines/ )
Thanks to Ken Fletcher and Mike Terry for regular updates. Links can be found on my web page.

July 2008

2008-06-19T18:54:00.001+01:00

Propagation Forecast

The second half of June will have seen 2 minor disturbances. On the 19th and 20th. The A index was at 10 and the K at 3, returning to ‘normal’ by the 21st with the A index at 5 and the K index at 2, until the 25th to the 27th with the A index peaking at 10 on the 26th. ‘Normal ‘ conditions will prevail until July 3rd to the 5th, with the A index again peaking at 10 on the 4th July. Things will remain ‘normal until 11th July with another disturbance until at least the 14th, the worst day being the 12th, with the A index peaking at 15 and the K index at 4.
Sunspots and Global Warming

The Spórer minimum (1420-1570) The Maunder minimum (1745-1615), and the Dalton Minimum (1790 to 1830) have coincided with a time when Earth’s climate was colder than average. The correlation has generated hypotheses that low solar activity produces cooler than average global temperatures, though a specific mechanism by which solar activity results in climate change has not been established.

Like the subsequent Maunder Minimum, the Spörer Minimum coincided with a time when Earth's climate was colder than average. This correlation has generated hypotheses that low solar activity produces cooler than average global temperatures, though a specific mechanism by which solar activity results in climate change has not been established.

Here is an interesting article in the Belfast Telegraph by Dr David Whitehouse (12 May 2007):
Can the Sun Save Us from Global Warming? (Low Sunspot Activity)
"Something is happening to our Sun. It has to do with sunspots, or rather the activity cycle their coming and going signifies. After a period of exceptionally high activity in the 20th century, our Sun has suddenly gone exceptionally quiet. Months have passed with no spots visible on its disc.
We are at the end of one cycle of activity and astronomers are waiting for the sunspots to return and mark the start of the next, the so-called cycle 24. They have been waiting for a while now with no sign it's on its way any time soon.
Sunspots – dark magnetic blotches on the Sun's surface – come and go in a roughly 11-year cycle of activity first noticed in 1843. It's related to the motion of super-hot, electrically charged gas inside the Sun – a kind of internal conveyor belt where vast sub-surface rivers of gas take 40 years to circulate from the equator to the poles and back. Somehow, in a way not very well understood, this circulation produces the sunspot cycle in which every 11 years there is a sunspot maximum followed by a minimum. But recently the Sun's internal circulation has been failing. In May 2006 this conveyor belt had slowed to a crawl – a record low. Nasa scientist David Hathaway said: "It's off the bottom of the charts... this has important repercussions for future solar activity." What's more, it's not the only indicator that the Sun is up to something.
Astronomers called it the "Maunder Minimum." It was an astonishing discovery: our Sun can change. Between 1645 and 1715 sunspots were rare. About 50 were observed; there should have been 50,000.
Ever since the sunspot cycle was discovered, researchers have looked for its rhythm superimposed on the Earth's climate. In some cases it's there but usually at low levels. But there was something strange about the time when the sunspots disappeared that left scientists to ponder if the sun's unusual behaviour could have something to do with the fact that the 17th century was also a time when the Earth's northern hemisphere chilled with devastating consequences."

THE SUN'S CHILLY IMPACT ON EARTH
A new NASA computer climate model reinforces the long-standing theory that low solar activity could have changed the atmospheric circulation in the Northern Hemisphere from the 1400s to the 1700s and triggered a "Little Ice Age" in several regions including North America and Europe. Changes in the sun's energy was one of the biggest factors influencing climate change during this period, but have since been superceded by greenhouse gases due to the industrial revolution. (NASA News).
(Thanks to Ken Fletcher and Mike Terry for regular updates). Links to the full articles are on my website. http://www.jameswelsh.org.uk

June 2008

2008-05-22T21:21:00.001+01:00

Propagation Summary
A recurrent coronal hole (CH327) was in an Earth facing position on May 18-19. Another recurrent coronal hole (CH328) rotated into an Earth facing position on May 23-25.
Following a disturbance around 21st May, with the A index at 25, and the K at 5, conditions will have settled down by 23rd May, with the A index at 10 and the K at 3 where it will remain until May 31st with the A rising to 10 and the K index remaining at 3 until 3rd June when the A will drop to 5 and the K to 2.
The Solar Flux, however will drop from 72 to 68 by 25th May until 9th June when it will rise to 70. This is then followed by another rise to 72 by the 12th where it will remain until at least the 16th.
Long distance low and medium frequency (below 2 MHz) propagation along paths north of due west over high and upper middle latitudes is poor. Propagation on long distance northeast-southwest paths is fair.
(From WWM7D.com, NOAA and www.dxlc.com/solar).

The Ionosphere
Scientists call the ionosphere an extension or a part of the thermosphere. So technically, the ionosphere is not another atmospheric layer, but a region of the atmosphere. The ionosphere represents less than 0.1% of the total mass of the Earth's atmosphere. Even so, it is extremely important!
The upper atmosphere is ionized by solar radiation. Under normal conditions free electrons and ions tend to recombine and a balance is established between electron and ion production and loss.
Ionization processes release energy, which heat up the upper atmosphere. So temperature increases with height in the ionosphere region to the extent that by 150-200km, the Earth's atmosphere is extremely hot compared to surface temperatures.
Different regions of the ionosphere make long distance radio communication possible by reflecting the radio waves back to Earth. It is also home to auroras and the mega-ampere currents that heat the atmosphere at high latitudes during geomagnetically active times. During storms, depletions and enhancements of ionization occur depending on the local time and geographical location.
Aeronomy is a term of recent origin, which is applied to the processes, both physical and chemical, of the ionosphere. From http://www.windows.ucar.edu/ (University Of Michigan)

HF Propagation Predictions For 2008
Here is an interesting website by G4FKH, which has a monthly chart of predicted HF conditions listed by capital cities: http://uk.geocities.com/g4fkh@btinternet.com/
See also: http://www.hfradio.org/propagation.html

The New Shortwave Propagation Handbook (Paperback) - by George Jacobs, Theodore J. Cohen, R. B. Rose. The NEW Shortwave Progagation Handbook may well be the only book you'll need on the subject of ionospheric propagation! It is a "must read" for Radio Amateurs, Shortwave Listeners, and radio communicators of any type who need to make the most productive use of the radio spectrum, regardless of the time of day, the season of the year, or the state of the sunspot cycle. It will become your ever-present companion the operating table as you master the art of shortwave radio progagation. (Available from Amazon.com posted from the USA)
Thanks to KF and MET for regular updates.

Propagation Report May 2008

2008-05-02T03:15:00.001+01:00

Propagation Forecast

The last week in April has been quite stable following a minor disturbance on the 23rd apparently caused by a coronal hole. Details at: http://www.dxlc.com/solar/
From 27th to the 30th, the index has remained at 5 and the K at 2. The first week in May will be quite disturbed. On the 2nd May, the A index will peak at 20 and the K at 5, then by the 8th May, conditions will settle with the A index at 5 and the K index at 2 until May19th when conditions are likely to deteriorate with the A index rising to 10 and the K index to 3. The solar flux has a downward trend remaining at 75 for the last week in April, then dropping to 70 by 2nd May where it will remain till the 19th May when it again rises to 75.
(Via wm7d.net)

Propagation explained:
The Ionosphere: A collection of ionized particles and electrons in the uppermost portion of the earth's atmosphere which is formed by the interaction of the solar wind with the very thin air particles that have escaped the earth's gravity. These ions are responsible for the reflection or bending of radio waves occurring between certain critical frequencies with these critical frequencies varying with the degree of ionization. As a result, radio waves having frequencies higher the lowest usable frequency (LUF) but lower than the maximum usable frequency (MUF) are propagated over large distances.

D-Layer:
The lowest part of the ionosphere, the D-layer appears at an altitude of 50-95km. This layer has a negative effect on radio waves because it only absorbs radio-energy, particularly those frequencies below 7MHz. It develops shortly after sunrise and disappears shortly after sunset. This layer reaches maximum ionization when the sun is at its highest point in the sky and this layer is also responsible the complete absorption of sky waves from the 80m and 160m amateur bands as well as the AM broadcast band during the daytime hours.

E-layer:
This part of the ionosphere is located just above the D-layer at an altitude of 90-150km. This layer can only reflect radio waves having frequencies less than 5MHz. It has a negative effect on frequencies above 5MHz due to the partial absorption of these higher frequency radio waves. The E-layer develops shortly after sunrise and it disappears a few hours after sunset. The maximum ionization of this layer is reached around midday and the ions in this layer are mainly O2+.
F-layer:
Highest part of the ionosphere. The F-layer appears a few hours after sunset, when the F1- and F2-layers merge. The F-layer is located between 250km and 500km in altitude. Even well into the night, this layer may reflect radio waves up to 20 MHZ, and occasionally even up to 25 MHZ. Ions in the lower part of the F-layer are mainly NO+ and are predominantly O+ in the upper part.
Thanks to Mike Terry and Ken Fletcher for regular updates.

Propagation Report April 2008

2008-03-22T01:13:00.000Z

Propagation Forecast

The Solar flux has remained at a steady 70 throughout March and this should continue until at least mid-April. However, the A and K Index are a different story. Over the Easter weekend, the A Index has remained at 5 and the K Index at 2. There will have been a serious disturbance of HF reception from 25th to the 29th March with the K Index rising to 5. The worst day of March being the 27th, with the A Index also peaking at 25. This is due to a coronal hole rotating into an earth-facing position, and pointing towards the Council Estate on March 23rd. The next disturbance will be from 4th to 11th April peaking on the 7th, with the A Index at 25, and the K Index at 5. Regularly updated Solar Terrestrial Activity Reports and forecasts, plus regional and frequency specific information can be found at: http://www.dxlc.com/solar/

Coronal Stream Activity
Coronal Streams are responsible for the recent disturbances. They are streams of charged particles originating from the sun's corona. Coronal streams have similar effects as CME's (Coronal Mass Ejections) by increasing the A- and K-indices but usually to a lesser extent. However, a few coronal holes may cause major storm levels at the higher latitudes on earth resulting in total propagation fade-out at these latitudes.

IMO Meteor Shower Calendar 2008.
The International Meteor Organisation has an online Meteor Shower Calendar for 2008, which includes a detailed summary for the year. The web address is:
http:// www.imo.net/calendar/2008

Solar Cycle 24
The Solar flux readings indicate that we are still awaiting some activity for Solar Cycle 24. Daily reports and the latest SOHO (the Solar and Heliospheric Observatory) images can be found at: http://www.solarcycle24.com or you can find out more about SOHO at: http://sohowww.nascom.nasa.gov/ Space weather alerts can also be found at: http://www.swpc.noaa.gov/alerts

This month’s links and more can be found at: http://www.jameswelsh.co.nr

Propagation Report March 2008

2008-02-23T14:19:00.000Z

During the second half of February, the Solar flux has remained at a constant 72, and is likely to remain the same until at least 17th March, which would suggest that we may at last have reached sunspot minimum at the start of Solar Cycle 24.
The A index rose to 12 on February 21st, and dropped back to 5 the next day. The next disturbance will be on Feb 28th, to March 3rd with the index at 15 and the K at 4 followed by another disturbance 8-13th with the A index peaking at 15 on the 8th and 9th. The A index will then rise again to 10 by the 16th for at least 2 days.
In conclusion, the best days for HF reception will be March 4th 5th 14th and 15th with the A index at 5 and the K index at 2, the worst days being the 1st, 8th 9th and 15th.
The National Oceanic and Atmospheric Administration and the US Air Force have predicted the solar flux to remain at 72 from March 1st continuing into April. (From: www.arrl.org)
Maunder Minimum?

It has been suggested that we may be entering another Maunder Minimum, which is the name given to the period roughly from 1645 to 1715, when sunspots became exceedingly rare, as noted by solar observers of the time. It is named after the solar astronomer Edward W. Maunder (1851–1928) who discovered the dearth of sunspots during that period by studying records from those years. During one 30-year period within the Maunder Minimum, for example, astronomers observed only about 50 sunspots, as opposed to a more typical 40,000–50,000 spots. See: http://en.wikipedia.org/wiki/Maunder_minimum

However, Tad Cooke of ARRL, after seeking the opinion of Dr. Kenneth Tapping of the Herzberg Institute of Astrophysics in Penticton, British Columbia recently wrote:
"I think we can relax about any possible upcoming 70-year period of a quiet Sun. We cannot say that it could not happen, but in fact there is nothing unusual about the current Solar Cycle minimum, and really no known method of predicting such a period."
Thanks to Mike Terry and Ken Fletcher for regular updates. Related links can be found at www.jameswelsh.co.nr.

Propagation February 2008

2008-02-05T09:00:00.000Z

Propagation Forecast

The second half of January has remained calm with but February will start off disturbed with the A index at 15, and the K at 4. By the 5th Feb, the A will have dropped to 5, and the K to 2, remaining calm until the 9th, when the A index rises to 15 and the K index to 4. By February 14th, conditions will have settled down again, with the A index at 5 and the K at 2, remaining the same until at least the 18th.
The Solar Flux however, is on a downward trend for February, starting off at 80, then dropping to 75 by the 4th and again dropping to 70 by the 14th. In conclusion, HF reception conditions for February should start off disturbed till the 4th, remaining calm till the 8th. The 9th to the 13th will again be disturbed then conditions should remain calm from the 14th. (Based on the 28 day forecast From WM7D.net)

Solar Cycle 23 VS Solar Cycle 24
There is still much debate among the experts about the emergence of Solar Cycle 24. According to this article from ARRL, (http://www.arrl.org/news/stories/2008/01/18/100/) "Old Cycle 23 spots will appear near the Sun's equator. The first spots of Cycle 24 are at a high solar latitude and will have magnetic polarity opposite of the old spots. There was a brief appearance on January 11 by an "almost sunspot" that had disappeared by the following day; it appeared to be a Cycle 24 spot -- with polarity reversed from Cycle 23 spots -- but it was near the equator, which is the wrong place for a new cycle sunspot."
However, looking at the sunspot number chart on http://www.solarcycle24.com/indexdx.htm sunspot numbers have definitely been on a downward trend. April 2006 had the highest sunspot number of 105, compared with April 07 when it was down to 38. It then peaked at 63 in June 07, and has again been on a downward trend remaining at 15 in October and November 07. Then December '07, saw a significant rise to 44.
Propagation Websites.

‘The Basics Of Radio Wave Propagation’ by Edwin C. Jones, MD, PhD (AE4TM) covers the subjects of Aurora, Backscatter and Grey Line propagation and related subjects, plus Maximum User Frequencies etc. The URL is: http://ecjones.org/propag.html. The XE1BEF website has a comprehensive links page of propagation software and specialist websites, although their bulletin is not currently available in English. http://members.fortunecity.com/xe1bef/propagation.htm. Thanks to Mike Terry and Ken Fletcher for links and updates. Links from this article can be found at http://www.jameswelsh.co.nr/

January 2008

2008-01-08T12:53:00.000Z

PROPAGATION REPORT
with James Welsh propagation@bdxc.org.uk
_______________________________________________________________________
Propagation Forecast
The second half of December remained fairly calm with the Solar A Index at 5 and the K at 2. This situation should remain, (as far as the A and K are concerned), until January 6th when the A index will peak at 12, but will settle back to 5 by the 9th, followed by a more serious disturbance on 13th to the 15th Jan with the A index at 15, and the K at 4. The Solar Flux however, after remaining at 72 for most of December, will rise 85 by Jan 4th, dropping back to 72 by the 16th. In conclusion, January 2nd to the 20th will probably be quite disturbed, propagation-wise, with the worst days being the 7th and 8th plus the 17th and 18th.
Solar Cycle 24.

Following general speculation about whether we have reached ‘Sunspot Minimum, here is an article from radioworld.com via Mike Terry:Since Solar Cycle 23 peaked between 2000 and 2003, solar activity has been declining. Amateur radio operators and shortwave listeners have been closely watching for the new cycle to start, knowing increasing solar activity will lead to higher maximum usable frequencies (MUF) and better high-frequency propagation. Satellite operators and TV engineers at stations on low VHF channels are also watching the solar cycle, but their concerns are that solar storms could damage satellites and higher MUF could allow distant stations to interfere with TV reception.He explained, "New solar cycles always begin with a high-latitude, reversed polarity sunspot." "Reversed polarity" means a sunspot with opposite magnetic polarity compared to sunspots from the previous solar cycle. "High-latitude" refers to the sun's grid of latitude and longitude. Old cycle spots congregate near the sun's equator. New cycle spots appear higher, around 25 or 30 degrees latitude, according to the NASA Science news release. More time is needed to see if this sunspot really is the start of Solar Cycle 24."Peaking in 2011 or 2012, the cycle to come could have significant impacts on telecommunications, air traffic, power grids and GPS systems," NASA said. Due to the increased use of telecommunications, there is concern the coming cycle could have a greater impact than the previous cycle. We won't have to worry about this for a few more years, however, as the solar cycles usually take a few years to peak. "We still have some quiet times ahead," Hathaway said. From: www.radioworld.com

You will find links to these articles and more at: http://clik.to/radioprop