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
Saturday, 24 July 2010
Saturday, 26 June 2010
July 2010
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)
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)
Wednesday, 19 May 2010
June 2010
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
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
Saturday, 24 April 2010
May 2010
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 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.
Friday, 26 March 2010
April '10
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)
(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)
Friday, 26 February 2010
March 2010
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.
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.
Friday, 29 January 2010
February '10
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 )
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 )
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