Metallic photos of the sun by renowned photographer Greg Piepol bring together the best of art and science. Buy one or a whole set. They make a stellar gift. | | | CHANCE OF FLARES: NOAA forecasters have upgraded the chance of X-class solar flares today to 20%. The source would be AR1339, one of the biggest sunspots in many years. The active region rotated over the sun's eastern limb two days ago and now it is turning toward Earth. Solar flare alerts: text, voice. The sunspot has already unleashed one X-flare on Nov. 3rd around 2027 UT. A movie from NASA's Solar Dynamics Observatory shows the extreme ultraviolet flash: The flare created waves of ionization in Earth's upper atmosphere, altering the normal propagation of radio waves over Europe and the Americas. In Ireland, the flare's effect was felt even after dark. A cloud of plasma or "CME" raced away from the blast site at 1100 km/s. The CME is not heading for Earth. It is, however, heading for Mercury and Venus. Click on the arrow to view a movie of the CME's forecast track: Analysts at the Goddard Space Weather Lab say the CME will hit Mercury on Nov. 4th around 16:14 UT. NASA's MESSENGER probe in orbit around Mercury will be monitoring the effects of the impact. If the CME overwhelms Mercury's relatively weak magnetic field, it could scour material off the planet's surface creating a temporary atmosphere and adding material to Mercury's comet-like tail. The CME should hit Venus on Nov. 5th; the gossamer cloud will probably break harmlessly against the top of planet's ultra-dense atmosphere. October 2011 Aurora Gallery [previous Octobers: 2010, 2009, 2008, 2007, 2006, 2004, 2003, 2002] Potentially Hazardous Asteroids ( PHAs) are space rocks larger than approximately 100m that can come closer to Earth than 0.05 AU. None of the known PHAs is on a collision course with our planet, although astronomers are finding new ones all the time. On November 4, 2011 there were 1256 potentially hazardous asteroids. Notes: LD means "Lunar Distance." 1 LD = 384,401 km, the distance between Earth and the Moon. 1 LD also equals 0.00256 AU. MAG is the visual magnitude of the asteroid on the date of closest approach. | The official U.S. government space weather bureau | | The first place to look for information about sundogs, pillars, rainbows and related phenomena. | | Researchers call it a "Hubble for the sun." SDO is the most advanced solar observatory ever. | | 3D views of the sun from NASA's Solar and Terrestrial Relations Observatory | | Realtime and archival images of the Sun from SOHO. | | from the NOAA Space Environment Center | | the underlying science of space weather | |