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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 368.8 km/sec
density: 2.0 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: M4
1816 UT Dec25
24-hr: M4
1816 UT Dec25
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 25 Dec 11
Sunspot 1385 is growing rapidly and poses an increasing threat for Earth-directed flares. It produced an impulsive M4-class flare on Dec. 25 at 1816 UT. Credit: SDO/HMI
Sunspot number: 101
What is the sunspot number?
Updated 24 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 24 Dec 2011

The Radio Sun
10.7 cm flux: 143 sfu
explanation | more data
Updated 24 Dec 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 1
explanation | more data
Interplanetary Mag. Field
Btotal: 4.0 nT
Bz: 1.7 nT north
explanation | more data
Updated: Today at 2345 UT
Coronal Holes: 25 Dec 11
A solar wind stream flowing from this coronal hole could reach Earth between Dec. 28th and 30th. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Dec 25 2200 UTC
0-24 hr
24-48 hr
50 %
50 %
05 %
05 %
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 25 2200 UTC
0-24 hr
24-48 hr
05 %
20 %
01 %
05 %
01 %
05 %
High latitudes
0-24 hr
24-48 hr
15 %
15 %
10 %
20 %
05 %
25 %
Sunday, Dec. 25, 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

SOLAR ACTIVITY PICKS UP: Dec. 25th began with a pair of magnetic filaments erupting in the sun's northern hemisphere followed by a sequence of C-flares from sunspot 1385 in the sun's southern hemisphere. Both halves of the sun are rocking on Christmas: SDO movie. Coronagraph images from SOHO and the twin STEREO probes suggest a possible Earth-directed CME. Stay tuned for updates.

RUSSIAN RE-ENTRY: The body of a Russian rocket that propelled a Soyuz spacecraft toward the International Space Station on Dec. 21st fell back to Earth on Christmas Eve. Roman Breisch sends this picture of the re-entry from Erdweg, 20 miles west of Munich, Germany:

"This is what the Christmas star looks like in the 21st century," says Breisch. " The decaying rocket was spectacular look as it wove over the night sky from West to the East, getting brighter and brighter and splitting up into hundreds of shiny pieces."

A video of the re-entry is being widely viewed on Youtube.

Meanwhile, the three astronauts (Don Pettit, Oleg Kononenko and Andre Kuipers) who rode this rocket to Earth orbit are settling in comfortably on the International Space Station. Don Pettit's return to the ISS is welcomed by readers of, who look forward to new episodes of Saturday Morning Science and Pettit's trademark astrophotography.

COMET LOVEJOY FROM ORBIT: Veteran astronaut Dan Burbank has seen many amazing things. Once, he even flew through the aurora borealis. So when Burbank says "[Comet Lovejoy] is the most amazing thing I have ever seen in space," it really means something. Currently serving onboard the International Space Station, Burbank photographed the sungrazing comet on Dec. 21st, an experience he describes in this NASA video:

Burbank describes the tail of Comet Lovejoy as a "green glowing arc at least 10 degrees long." He saw it just before orbital sunrise emerging from Earth's limb, which was "lit up as a bright sliver of blue and purple."

After plunging through the sun's atmosphere only 120,000 km above the stellar surface on Dec. 16th, and improbably surviving, Comet Lovejoy has become the finest comet since Comet McNaught in 2007. Its orbit is carrying it through the skies of the southern hemisphere where sunrise sky watchers are seeing the comet almost as clearly as Burbank did. One wonders if Burbank was looking out the window on Dec. 24th when Carlos Caccia took this picture of the ISS transiting Lovejoy's tail over Intendente Alvear, Argentina:

"The ISS passed through the Southern Cross, continued parallel to the Milky Way, and finally arrived at the tail of Lovejoy with its typical golden color," says Caccia. "What a lucky shot!"

The visibility of Comet Lovejoy should continue to improve in he mornings ahead as the comet moves away from the sun into the darker skies before dawn. Sky watchers should set their alarm for an early-Christmas treat. [finder chart]

more images: from Scott Alder of Senic Lookout, Newcastle NSW Australia; from MENDONÇA JR of Caiobá Paraná Brazil; from Joe Perulero of Port Kembla NSW Australia; from Ben & Vic Levis of Perth Observatory, Bickley, Australia; from Rob Carew of Melbourne, Australia; from Mariano Ribas of Rawson, Argentina; from David Finlay of Kiama, NSW, Australia; from Eric Schmitt of Bauru, SP, Brasil; from Yuri Beletsky of Santiago, Chile; from Shane Ocean of Whitsundays, Australia; from Hernán Stockebrand of Vicuña, Chile; from Giovanni of Paysandù Uruguay; from Andy Dodson of Huirangi, New Zealand; from Rodolfo Chiaramonte of Vera Cruz, São Paulo, Brazil; from James Tse of Christchurch, New Zealand; from Emilio Lepeley of Vicuna, Chile; from Rogerio Marcon of Campinas SP Brasil; from Stephen Chadwick of Himatangi Beach, New Zealand; from Kosma Coronaios of Louis Trichardt, Limpopo Province, South Africa; from Paulo Morales Valdebenito of San Francisco de Mostazal, Chile; from Willian Souza of Sao Paulo, Brazil; from Grahame Kelaher of Perth, Western Australia; from Minoru Yoneto of Queenstown, New Zealand;

  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 25, 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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