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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 323.4 km/sec
density: 3.8 protons/cm3
explanation | more data
Updated: Today at 2347 UT
X-ray Solar Flares
6-hr max: C1
2121 UT Jan21
24-hr: C2
1342 UT Jan21
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 21 Jan 12
Sunspot 1401 poses a continued threat for M-class solar flares. Credit: SDO/HMI
Sunspot number: 88
What is the sunspot number?
Updated 20 Jan 2012

Spotless Days
Current Stretch: 0 days
2012 total: 0 days (0%)
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 20 Jan 2012

The Radio Sun
10.7 cm flux: 141 sfu
explanation | more data
Updated 20 Jan 2012

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 2
explanation | more data
Interplanetary Mag. Field
Btotal: 12.5 nT
Bz: 12.1 nT north
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 21 Jan 12
A coronal hole is emerging over the sun's SE limb. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2012 Jan 21 2200 UTC
0-24 hr
24-48 hr
35 %
35 %
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: 2012 Jan 21 2200 UTC
0-24 hr
24-48 hr
25 %
40 %
10 %
20 %
01 %
05 %
High latitudes
0-24 hr
24-48 hr
30 %
50 %
20 %
25 %
05 %
10 %
Saturday, Jan. 21, 2012
What's up in space

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

Meteorite jewelry

COMET CORPSES IN THE SOLAR WIND: A paper published in today's issue of Science raises an intriguing new possibility--the presence of abundant comet corpses in the solar wind. The new research is based on dramatic images of a comet disintegrating in the sun's atmosphere last July. [full story]

WHILE WAITING FOR THE CME... An incoming CME of Jan. 19th (see below) has not yet arrived. Nevertheless, auroras are already dancing around the Arctic Circle. This was the scene last night over Chatanika, Alaska:

"My fellow Fairbanks aurora chaser, Roger Marty, is shown here shooting a corona as the display began to peak," says photographer Ronn Murray. "Perhaps we got a sneak peak of what's to come with tomorrow's expected CME from sunspot AR1401."

Indeed, it could be a preview. NOAA forecasters are estimating as much as a 25% chance of polar geomagnetic storms when the CME arrives during the next ~36 hours. High latitude sky watchers should remain alert for auroras. Aurora alerts: text, voice.

more images: from Frank Olsen of Tromsø, Norway

January 2012 Aurora Gallery
[previous Januaries: 2010, 2009, 2008, 2007, 2005, 2004]

INCOMING CME: Active sunspot 1401 erupted on Jan. 19th around 16:30 UT, producing an M3-class solar flare and a full-halo coronal mass ejection (CME). The Solar and Heliospheric Observatory recorded the cloud expanding almost directly toward Earth:

Analysts at the Goddard Space Weather Lab say strong geomagnetic storms are possible when the cloud arrives this weekend. Their animated forecast track predicts an impact on Jan. 21st at 22:30 UT (+/- 7 hrs).

The cloud is also heading for Mars, due to hit the Red Planet on Jan. 24th. NASA's Curiosity rover, en route to Mars now, is equipped to study solar storms and might be able to detect a change in the energetic particle environment when the CME passes by.

more images: from the Charlie Bates Solar Astronomy Project of Atlanta, GA; from Theo Ramakers of Social Circle, GA; from Jim Haklar of Edison, New Jersey; from Zach, Annissa, and Annie of The G.W. Hinckley School in Hinckley, Maine

INCREASING SOLAR ACTIVITY CLEANS UP SAT-DEBRIS: Earth's atmosphere has been puffing up in response to increasing levels of UV radiation from sunspots. This is good news for satellite operators, because a puffed up atmosphere helps clean up low-Earth orbit. "The number of cataloged debris in Earth orbit actually decreased during 2011," reports Nick Johnson in NASA's Orbital Debris Quarterly newsletter. "[The figure below] illustrates how the rate of debris reentries from the Fengyun-1C anti-satellite test of January 2007 increased during the past year."

"Even though only 6% of the total 3218 cataloged debris from the ill-advised engagement had reentered by the end of 2011, half of these debris fell out of orbit in the past 12 months," he points out. "Likewise, many debris from the 2009 accidental collision of Cosmos 2251 and Iridium 33 are accelerating their departure from Earth orbit. In the absence of a new major satellite breakup, the overall orbital debris population should continue to decrease during 2012 and 2013."

Comet Lovejoy Gallery
[previous comets: McNaught, Holmes, Lulin, Tuttle, Ikeya-Zhang]

  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 January 21, 2012 there were 1272 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2012 BX1
Jan 15
8.1 LD
48 m
2012 BT1
Jan 15
9.4 LD
15 m
2012 AQ10
Jan 16
2.2 LD
20 m
2011 YH40
Jan 16
5.4 LD
109 m
2012 BV1
Jan 20
0.8 LD
3 m
2012 BS1
Jan 23
3.1 LD
8 m
2012 BY1
Jan 24
2.1 LD
28 m
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
1999 RD32
Mar 14
57.9 LD
2.3 km
2011 YU62
Mar 16
73.4 LD
1.3 km
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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