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.
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HOW DOES THE SUN DEVOUR A COMET? NASA is about to find out. On Valentine's Day, the Stardust-NExT spacecraft will swoop past Comet Tempel 1 for a six year check-up. High-resolution pictures will reveal how the comet's nucleus has been eroded by hot sunlight since another spacecraft, Deep Impact, visited the comet in 2005. Get the full story from Science@NASA.
FARSIDE SUNSPOT: Active sunspot 1153 rotated over the sun's western horizon yesterday, ending the possibility of an Earth-directed eruption. The sunspot will spend the next two weeks transiting the sun's far side -- out of sight, but not out of view. NASA's twin STEREO spacecraft are monitoring the far side, and they will never lose track of the active region. STEREO-A took this picture just hours ago:
Sunspot 1153 is circled. The sunspot's magnetic canopy is filled with hot plasma, which glows brightly in this extreme ultraviolet image. Surges of UV radiation seen in this 24-hour movie show that the active region is still active indeed.
You can follow AR1153 as it swings around the back of the sun. Just download NASA's 3D Sun app for the iPhone and iPad. The app allows you to spin the sun with a flick of your finger, zoom in to inspect active regions, and fly over the farside. Best of all, it's free. (Note: An Android version is in the works.)
HUBBLE FLARE: The Hubble Space Telescope (HST) is famous for many reasons, but visibility isn't one of them. On most nights, the great observatory registers a modest +3 on the magnitude scale, making a disappointingly faint streak as it moves among the stars. But every now and then, Hubble flares:
"I didn't know Hubble could do this," says M. Raşid Tuğral of Antalya, Turkey, who took the picture on Feb. 7th. "The HST suddenly flared to magnitude -2, almost as bright as the planet Jupiter." This is the kind of streak you could see even from brightly-lit cities; in the remote Turkish countryside, "it was dazzling."
Although not widely publicized, Hubble flares have been observed for years by members of the satellite-watching community. The luminous outbursts are caused by sunlight glinting from one of the spacecraft's flat surfaces--possibly the telescope's aperture door or its "aft skirt." Predicting Hubble flares is tricky because they depend sensitively on the telescope's observing schedule. Slewing from one galaxy to another, stopping for calibration, detouring to a newly-reported supernova: any of these actions could produce--or forestall--an absolute shadow-caster.
The only way to see a Hubble flare is to take a chance on looking. Let your cell phone be your guide.
February 2011 Aurora Photo Gallery
[previous Februaries: 2010, 2009, 2008, 2007, 2006, 2004, 2003, 2002]