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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 405.4 km/sec
density: 2.9 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: C1
1950 UT Dec04
24-hr: C4
1615 UT Dec04
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 04 Dec 11
Sunspot 1363 is growing rapidly and poses a threat for M-class solar flares. Credit: SDO/HMI
Sunspot number: 138
What is the sunspot number?
Updated 03 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 03 Dec 2011

The Radio Sun
10.7 cm flux: 160 sfu
explanation | more data
Updated 03 Dec 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 2
explanation | more data
Interplanetary Mag. Field
Btotal: 3.8 nT
Bz: 1.2 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 04 Dec 11
Earth is inside a solar wind stream flowing from the indicated coronal hole. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Dec 04 2200 UTC
0-24 hr
24-48 hr
30 %
30 %
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 04 2200 UTC
0-24 hr
24-48 hr
02 %
02 %
01 %
01 %
00 %
00 %
High latitudes
0-24 hr
24-48 hr
14 %
14 %
09 %
09 %
03 %
03 %
Sunday, Dec. 4, 2011
What's up in space

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.

Metallic pictures of the Sun

SUPER-SIZED ECLIPSE: On Saturday morning, Dec. 10th, sky watchers in the western United States and Canada will witness a total lunar eclipse swollen to super-sized proportions by the Moon illusion. Get the full story from Science@NASA.

GROWING THREAT OF FLARES: Sunspot AR1363 is growing rapidly, more than doubling in size since Friday. A 48-hour movie from NASA's SOlar Dynamic Observatory shows the expansion:

The active region has a "beta-gamma" magnetic field that harbors energy for M-class solar flares. Because of AR1363's location near the center of the solar disk, any such eruptions in the days ahead would be Earth-directed. Solar flare alerts: text, phone.

more images: from Göran Strand of Frösön, Sweden; from John Stetson of Falmouth, Maine

AURORA EXPLOSION: Last night on the border between Russia and Norway, the sky suddenly erupted in color. "It was like an aurora explosion," says
Sebastian Voltmer of Kirkenes, Norway. "I was surprised to see a brightening snake forming an 'S' - like the first letter of my name, that appeared at 22.48 pm UT."

During the outburst, Jupiter was surrounded by streamers of green light. "A very beautiful event!" says Voltmer.

Auroras like these have been flickering and surging around the Arctic Circle for days. The source of the displays is a solar wind stream, which has been buffeting Earth's magnetic field since the month began. NOAA forecasters estimate a 13% chance of more polar geomagnetic activity tonight. Aurora alerts: text, phone.

more images: from Casey Thompson of Fairbanks, AK; from Yuichi Takasaka of Yellowknife, Northwest Territories, Canada; from Frank Olsen of Tromsø, Norway; from Göran Strand of Frösön, Sweden; from Don Derosier of Murphy Dome, Fairbanks, Alaska; from Ronn Murray of Fairbanks, Alaska

  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 4, 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
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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