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QUIET SUN: All of the sunspots on the Earthside of the sun are magnetically simple and quiet, and the sun's X-ray output has consequently flatlined. NOAA forecasters estimate the chance of significant flares today to be no more than 1%. Solar flare alerts: text, voice.
AURORA WATCH: Earth passed through a minor solar wind stream on Feb. 4-5. The weak impact of the solar wind was just enough to spark auroras around parts of the Arctic Circle. Frank Olsen sends this 20-second exposure from the waterfront outside Tromsø, Norway:
"Despite bright moonlight and low solar activity, there were some great auroras last night," says Olsen.
The effects of the solar wind are subsiding, and the auroras might disappear into the moonlight for the next few nights. Geomagnetic activity is expected to hover at low levels for the next 48 hours. Aurora alerts: text, voice.
more images: from Oivind Toien of Fairbanks, Alaska
BE ALERT FOR MOON HALOES: With the full Moon less than a week away, now is the time to be alert for Moon haloes. Tom Soetaert photographed this spooky specimen over Lawrence, Kansas, on Feb. 2nd:
Moon halos are formed by ice crystals in high clouds, which catch moonbeams and bend them as shown. The brighter the Moon, the brighter the Moon halo, so any halos this weekend should be very bright indeed. The Moon is full on Feb. 7th. Browse the links below for more examples of what's in store.
more images: from Chris Cook of Cape Cod, Massachusetts; from Joni Niemelä of Western Finland; from Mike Peters of Green Bay, Wisconsin; from Tamas Ladanyi of Veszprem (Hungary); from Schmaus Thomas of Oberbernbach, Bavaria, Germany; from Domenico Licchelli of Gagliano del Capo, Italy; from Primoz Kuk of Sempeter pri Gorici, Slovenia; from Dr. Salvador Aguirre of Hermosillo, Sonora, Mexico; from György Soponyai of Dunakeszi, Hungary
January 2012 Aurora Gallery
[previous Januaries: 2010, 2009, 2008, 2007, 2005, 2004]
Comet Lovejoy Gallery
[previous comets: McNaught, Holmes, Lulin, Tuttle, Ikeya-Zhang]
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 February 5, 2012 there were 1287 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters: Asteroid | Date(UT) | Miss Distance | Mag. | Size |
2012 CU | Jan 31 | 2.4 LD | -- | 29 m |
2009 AV | Feb 16 | 44.9 LD | -- | 1.2 km |
2000 ET70 | Feb 19 | 17.7 LD | -- | 1.0 km |
2011 CP4 | Feb 23 | 9.1 LD | -- | 255 m |
2008 EJ85 | Mar 6 | 9.1 LD | -- | 44 m |
1999 RD32 | Mar 14 | 57.9 LD | -- | 2.4 km |
2011 YU62 | Mar 16 | 73.3 LD | -- | 1.4 km |
1996 SK | Apr 18 | 67.2 LD | -- | 1.6 km |
2007 HV4 | Apr 19 | 4.8 LD | -- | 8 m |
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 |