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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 243.2 km/sec
density: 0.1 protons/cm3
explanation | more data
Updated: Today at 2341 UT
X-ray Solar Flares
6-hr max: C6
2226 UT Dec27
24-hr: C8
0422 UT Dec27
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 27 Dec 11
Sunspots 1386 and 1387 have "beta-gamma" magnetic fields that harbor energy for M-class solar flares. Credit: SDO/HMI
Sunspot number: 110
What is the sunspot number?
Updated 26 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 26 Dec 2011

The Radio Sun
10.7 cm flux: 146 sfu
explanation | more data
Updated 26 Dec 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 0
explanation | more data
Interplanetary Mag. Field
Btotal: 7.8 nT
Bz: 5.4 nT north
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 27 Dec 11
A solar wind stream flowing from this coronal hole could reach Earth between Dec. 29th and 30th. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Dec 27 2200 UTC
0-24 hr
24-48 hr
70 %
70 %
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 27 2200 UTC
0-24 hr
24-48 hr
20 %
25 %
05 %
10 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
20 %
15 %
25 %
30 %
20 %
40 %
Tuesday, Dec. 27, 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

MORE SUNSET PLANETS: On Dec. 27th, for the second night in a row, Venus and the crescent Moon are lining up in the western sky for a beautiful sunset conjunction. Go outside when the sun goes down and enjoy the show. (Scroll past the CME for scenes from Dec. 26th.)

CMEs TARGET EARTH, MARS: The odds of a geomagnetic storm on Dec. 28th are improving with the launch of two CMEs toward Earth in less than 24 hours. NASA's STEREO-B spacecraft photographed this one on Dec. 26th:

According to a forecast track prepared by analysts at the Goddard Space Weather Lab, the cloud should squarely strike Earth's magnetic field on Dec. 28th at 20:22 UT (+/- 7 hours). Another CME could deliver a glancing blow a few hours earlier on the same date. The double impact is expected to spark mild-to-moderate geomagnetic storms at high latitudes. Aurora alerts: text, voice.

Mars is also in the line of fire. The first of the two CMEs is squarely directed toward the Red Planet--estimated time of arrival: Dec. 30th at 1800 UT. Using onboard radiation sensors, NASA's Curiosity rover might be able to sense the CME when it passes the rover's spacecraft en route to Mars.

VENUS AND THE MOON: On the night after Christmas, the heavens delivered a belated present--a conjunction of Venus and the crescent Moon. Robert Arn sends this picture from Fort Collins, Colorado:

"I arrived at the observing site a few minutes before sunset," says Arn. "Minutes after the sun disappeared behind the mountains I saw a very slender moon pop out of the cold, crisp sky. Soon, Venus joined the show. Over the next two hours I watched the sky turn hundreds of shades of blues, pinks, purples, and blacks as the two heavenly bodies slowly crept across the sky."

more images: from Miguel Claro of Fonte-de-Telha, Portugal; from Robert Snache of Rama First Nation, Ontario; from Stefano De Rosa of Viverone Lake (Turin, Italy); from Mike O'Leary of San Diego, California; from Tavi Greiner of Ocean Isle Beach, NC; from Maximilian Teodorescu of Sinaia, Romania; from Francesco Finazzi of Chiuduno, Bergamo, Italy; from Joe Ziolkowski of Ithaca, NY; from Alex Roca of Hortoneda, Lleida Spain; from Kevin Jung of Grand Rapids, Michigan; from David Smoyer of Truckee, CA; from Megan O'Leary of Captiva, Florida; from Mike O'Leary of El Cajon, CA; from Andreas Walker of Altenrhein, Switzerland; from Ken Maytag of Carpintetia, California; from Adrian New of San Antonio, Texas; from Joe Ricci of Rochester, New York; from Mark Williams of Geneva, Switzerland; from Robert Sparks of Tucson, Arizona; from Gustavo Rojas of São Carlos, SP, Brazil; from Don Roberts of Wintersville, Ohio; from Randy Hollaway of Pittsburgh PA; from Joseph M. Golebieski of Toms River, NJ; from Joe Stieber of Atsion, NJ; from Rob Ferber of Kihei, Maui, Hawaii

  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 27, 2011 there were 1272 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2011 YQ1
Dec 14
1 LD
32 m
2000 YA
Dec 26
2.9 LD
80 m
2011 SL102
Dec 28
75.9 LD
1.0 km
2011 WS95
Dec 28
7.1 LD
46 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
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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