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