SOLAR FLARE! Sunspot 1112 erupted today at 1900 UT, producing the brightest solar flare in nearly three months. Click here to view a movie of the M1-class explosion from NASA's Solar Dynamics Observatory.
GREAT FILAMENT: A vast filament of magnetism is cutting across the sun's southern hemisphere today. Run a finger along the golden-brown line in this extreme UV image from the Solar Dynamics Observatory and your digit will have traveled more than 400,000 km:
A bright 'hot spot' just north of the filament's midpoint is UV radiation from sunspot 1112. The proximity is no coincidence; the filament appears to be rooted in the sunspot below. If the sunspot flares, it could cause the entire structure to erupt.
UPDATE: Today's M1-flare did not destabilize the filament. Stay tuned, however, because sunspot 1112 is growing and more activity is possible in the hours ahead. Readers with solar telescopes are encouraged to monitor developments.
more images: from Eric Roel of Valle de Bravo, México; from Francois Rouviere of Mougins, France; from Jo Dahlmans & Wouter Verhesen of Limburg, The Netherlands; from John Nassr of Baguio, Philippines; from Enrico Colzani of Sormano Astronomical Observatory, Italy; from Stephen Ramsden of Immaculate Heart of Mary Catholic School, Atlanta, GA; from Jean-Pierre Brahic of Uzès, France;
TIME TO SEE COMET HARTLEY: For backyard stargazers, the next few nights are the best time to see green Comet 103P/Hartley 2 as it approaches Earth for an 11-million-mile close encounter on Oct. 20th. Set your alarm for the dark hours before dawn, go outside, and look straight up. You will find Hartley 2 not far from the bright star Capella: sky map. Although the comet is barely visible to the unaided eye, it is easy to find in binoculars and looks great through a backyard telescope.
Doug Zubenel sends this picture (Oct. 9) from the Monument Rocks National Landmark in Kansas:
"To photograph the comet, I used a Canon Rebel XTi digital camera with an 85mm Nikkor lens," says Zubenel. "This picture is a single 2-minute exposure begun with the lens focused on the rocks, with a quick flash, then focus-shifted to infinity for the remainder of the time at ISO 800."
NASA scientists say 103P/Hartley 2 is one of the most active comets they've seen; it has a big atmosphere and copious outgassing from jets in the nucleus. Amateur astronomers are encouraged to monitor the action and submit their images here.
more images: from Rolando Ligustri using a robotic telescope in New Mexico; from Mike Broussard of Maurice, Louisiana; from Fredrik Broms of Kvaløya, Norway; from Tamás Ábrahám of Zsámbék, Hungary; from Efrain Morales Rivera of Aguadilla, Puerto Rico; from P-M Hedén of Vallentuna, Sweden; from Nick Howes using the Faulkes North Telescope in Hawaii.
October 2010 Aurora Gallery
[previous Octobers: 2009, 2008, 2007, 2006, 2004, 2003, 2002, 2001]
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 October 16, 2010 there were 1155 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 |