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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TIANGONG-1 SIGHTINGS: China's first space station, an 8.5-ton experimental module named Tiangong-1 (Heavenly Palace-1), is flying over the United States this week. Last night, Justin Cowart saw it gliding over Carbondale, Illinois. "At first it was a little difficult to pick out in the moonlight, but the the space station became a little brighter as rose into the sky: image. I'd say it held a fairly steady magnitude of +1.5, with no large change in brightness." Readers, check Spaceweather's Satellite Tracker for sighting opportunities in your hometown. You can also turn your smartphone into a Tiangong-1 tracker by downloading the Simple Flybys app.
more images: from Jim Saueressig II of Burlington, Kansas
AURORA BOREALIS LANE: Globally, Earth's magnetic field has been quiet on Oct. 3rd and 4th. Nevertheless, last night Ronn Murray was able to see bright Northern Lights over Fairbanks, Alaska. He took a stroll down Aurora Borealis Lane:
"I love living in Fairbanks," says Murray. "The sky is so beautiful. I grabbed this shot on the way home from work."
Displays like this could spread around the Arctic Circle on Oct. 5th and 6th when one or more CMEs propelled by recent eruptions on the sun reach Earth. NOAA forecasters estimate a 30% chance of geomagnetic storms at high latitudes. Aurora alerts: text, voice.
September 2011 Aurora Gallery
[previous Septembers: 2010, 2009, 2008, 2007, 2006, 2005, 2004]
COMET AND CME: A comet discovered by amateur astronomers on Friday, Sept. 30th, disintegrated in spectacular fashion the very next day when it plunged into the sun. The Solar and Heliospheric Observatory recorded the comet's last hours. The end was punctuated by an unexpected explosion:
Watch the movie again. The timing of the CME so soon after the comet dove into the sun suggests a link. But what? There is no known mechanism for comets to trigger solar explosions. Before 2011 most solar physicists would have discounted the events of Oct. 1st as pure coincidence--and pure coincidence is still the most likely explanation. Earlier this year, however, the Solar Dynamics Observatory (SDO) watched another sungrazer disintegrate in the sun's atmosphere. On July 5, 2011, the unnamed comet appeared to interact with plasma and magnetic fields in its surroundings as it fell apart. Could a puny comet cause a magnetic instability that might propagate and blossom into a impressive CME? The question is not so crazy as it once seemed to be.
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 4, 2011 there were 1250 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 |
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