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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 295.4 km/sec
density: 2.1 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: B6
2008 UT Dec06
24-hr: B9
0317 UT Dec06
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 06 Dec 11
Sunspot 1363 is experiencing the onset of decay and poses a subsiding threat for M-class solar flares. Credit: SDO/HMI
Sunspot number: 185
What is the sunspot number?
Updated 05 Dec 2011

Spotless Days
Current Stretch: 0 days
2011 total: 2 days (<1%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 821 days
Typical Solar Min: 486 days

Updated 05 Dec 2011

The Radio Sun
10.7 cm flux: 158 sfu
explanation | more data
Updated 05 Dec 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 1
explanation | more data
Interplanetary Mag. Field
Btotal: 2.0 nT
Bz: 0.2 nT south
explanation | more data
Updated: Today at 2345 UT
Coronal Holes: 06 Dec 11
There are no large coronal holes on the Earthside of the sun. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Dec 06 2200 UTC
0-24 hr
24-48 hr
20 %
20 %
01 %
01 %
Geomagnetic Storms:
Probabilities for significant disturbances in Earth's magnetic field are given for three activity levels: active, minor storm, severe storm
Updated at: 2011 Dec 06 2200 UTC
0-24 hr
24-48 hr
10 %
10 %
04 %
04 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
14 %
14 %
17 %
17 %
15 %
15 %
Tuesday, Dec. 6, 2011
What's up in space

Don't just watch shooting stars. Wear them! Authentic meteorite jewelry for Christmas is now available in the SpaceWeather Store.

Meteorite jewelry

TOTAL LUNAR ECLIPSE: Mark your calendar. On Saturday, Dec. 10th, the full Moon will glide through the coppery shadow of Earth, producing a total lunar eclipse visible from the Pacific side of our planet. For residents of the western USA and Canada, the event unfolds at dawn and will be magnified to super-sized proportions by the Moon illusion. [Science@NASA: full story, video]

THE MOON AND JUPITER: For the second night in a row, the Moon and Jupiter are in conjunction. Go outside just after sunset to see the pair rising in the east, shining brightly enough to pierce city lights and even thin clouds. Marek Nikodem,
sends this picture from Szubin, Poland:

"Bright moonlight shining through ice crystals in the air made a beautiful 22o halo," he says. "The ring of light was almost big enough to encircle Jupiter, too."

Nikodem took his picture on Dec. 4th when Jupiter and the Moon were only beginning to converge. Tonight the pairing is much tighter, with only 5o of separation between the two. Any Moon halo that forms this evening will capture Jupiter deep inside its circumference. This is a good night for observing in icy air!

more images: from Mike Hollingshead of Modale, Iowa; from Sven Melchert of Stuttgart, Germany; from Austin Taylor of Lerwick, Shetland Islands, UK; from Maxime Barreau of Cholet, France; from JimTegerdine of Marysville, Washington

SUBSIDING SUNSPOT: After three days of meteoric growth, sunspot AR1363 has reversed course and is beginning to decay. As its magnetic field relaxes, the active region poses a subsiding threat for strong flares. It's not dead yet, though, as this snapshot shows:

NASA's Solar Dynamics Observatory recorded this extreme ultraviolet flash from a C6-class solar flare in the sunspot's magnetic canopy during the late hours of Dec. 5th. AR1363 is crackling with low-level flares like this one.

There is still a slim chance that AR1363 will buck the trend and unleash a major M- or X-class eruption. If such an flare happens today, it will be geoeffective because the sunspot is facing Earth. Quiet, however, is more likely. Solar flare alerts: text, phone.

  Near Earth Asteroids
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 6, 2011 there were 1272 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2011 WV74
Dec 2
2.3 LD
13 m
2011 WU74
Dec 4
4.2 LD
23 m
2003 XV
Dec 7
1.1 LD
20 m
2003 WM7
Dec 9
47.6 LD
1.6 km
2000 YA
Dec 26
2.9 LD
80 m
2011 SL102
Dec 28
75.9 LD
1.0 km
1991 VK
Jan 25
25.3 LD
1.9 km
433 Eros
Jan 31
69.5 LD
8.5 km
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
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.
  Essential web links
NOAA Space Weather Prediction Center
  The official U.S. government space weather bureau
Atmospheric Optics
  The first place to look for information about sundogs, pillars, rainbows and related phenomena.
Solar Dynamics Observatory
  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
Solar and Heliospheric Observatory
  Realtime and archival images of the Sun from SOHO.
Daily Sunspot Summaries
  from the NOAA Space Environment Center
  the underlying science of space weather
Science Central
Trade Show Displays
  more links...
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