Hang the Transit of Venus on your wall! Hubble-quality images from NASA's Solar Dynamics Observatory are now available as metallic posters in the Space Weather Store. | | |
LUNAR IMPACTS TODAY: NASA's twin lunar gravity probes, nickhamed Ebb and Flow, will collide with a mountain near the Moon's north pole today, Dec. 17, at 5:28 pm EST. Get the full story from Science@NASA.
SOLAR WIND: Earth is entering a stream of high-speed solar wind. The source of the wind, a coronal hole on the sun, is shown in this image taken by NASA's Solar Dynamics Observatory during the early hours of Dec. 17th:
A coronal hole is a place in the sun's atmosphere where the solar magnetic field opens up and allows solar wind to escape. This particular coronal hole is located far down in the sun's southern's hemisphere, so the stream it is emitting is not heading directly for our planet. To some degree, this will mitigate its impact on Earth. At the moment, NOAA forecasters are estimating a relatively slight 20% chance of geomagnetic storms. Nevertheless, high-latitude sky watchers should be alert for auroras. Aurora alerts: text, voice.
Realtime Space Weather Photo Gallery
GEMINID METEOR RECAP: Earth has exited the debris stream of rock comet 3200 Phaethon, which brings an end to the annual Geminid meteor shower. On peak night, Dec. 14th, worldwide observers counted more than 100 meteors per hour, many of them fireballs (meteors brighter than Venus). David Clapp photographed this one streaking over the icy waters of Kirkjufell, Iceland:
"This was one amazing moment," says Clapp.
Note: Although the meteor appears to be flying mostly-above the auroras, it is more likely below. Geminid meteors burn up approximately 80 km above Earth's surface, while auroras stretch from 100 km to 500 km high.
Pictures of Geminids are still pouring in. Browse the photo gallery to see the most popular photos submitted so far:
"Most Popular" Geminid Photo Gallery
Realtime Aurora Photo Gallery
Realtime Noctilucent Cloud Photo Gallery
[previous years: 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2011]
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 December 17, 2012 there were 1360 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 |