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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 357.4 km/sec
density: 6.8 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: B6
2126 UT Dec19
24-hr: B8
1413 UT Dec19
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 19 Dec 11
Sunspot complex 1381-1382 is growing rapidly. Credit: SDO/HMI
Sunspot number: 103
What is the sunspot number?
Updated 18 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 18 Dec 2011

The Radio Sun
10.7 cm flux: 128 sfu
explanation | more data
Updated 18 Dec 2011

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: 4.9 nT
Bz: 2.4 nT south
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 19 Dec 11
There are no large coronal holes on the Earthside of the sun. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Dec 19 2200 UTC
0-24 hr
24-48 hr
01 %
01 %
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 19 2200 UTC
0-24 hr
24-48 hr
05 %
01 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
15 %
10 %
10 %
05 %
01 %
Monday, Dec. 19, 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

COMET LOVEJOY IN THE MORNING: Noted astronomer John Bortle urges observers (especially in the southern hemisphere) to "begin searching for Comet Lovejoy's bright tail projecting up out of the morning twilight beginning at dawn. The tails of some of the major sungrazing comets have been extraordinarily bright. Comet Lovejoy's apparition has been so bizarre up to this point that it is difficult to anticipate just what might happen next ... [including] the exact sort of tail it might unfurl in the morning sky."

This just in! The ghostly tail of Comet Lovejoy was sighted this morning shining through the twilight glow of dawn over Australia. Peter Sayers sends this picture from Devonport, Tasmania:

"I was surprised to be able to see Comet Lovejoy in our Tasmanian summer early morning twilight with the waning Moon," says Sayers. "The comet's tail was just barely naked eye and perhaps a degree long."

The visibility of the tail could improve in the days ahead as the comet moves away from the sun and the background sky darkens accordingly. Early rising sky watchers should be alert for this rare apparition. [finder chart]

SPIRAL COMET TAIL: As Comet Lovejoy recedes intact from its Dec. 16th close encounter with the sun, researchers are pondering a mystery: What made the comet's tail wiggle so wildly in transit through the sun's atmosphere? The effect is clear in this sequence of extreme UV images recorded by NASA's STEREO-B spacecraft:

"Why the wiggles?" wonders Karl Battams of the Naval Research Lab. "We're not sure. There might be some kind of helical motion going on. Perhaps we're seeing material in the tail magnetically 'clinging' to coronal loops and moving with them. [Coronal loops are huge loops of magnetism that emerge from the sun's surface and thread the sun's atmosphere.] There are other possibilities too, and we will certainly investigate those!"

Battams notes that these images can be combined with similar images from STEREO-A on the other side of the sun to produce a three dimensional picture. "When we pair these together, and throw in the SDO images too, we should be able to get an incredibly unique 3-D picture of how this comet is reacting the the intense coronal heat and magnetic loops. We are going to learn a lot."

TIANGONG 1 AND MARS: This week, China's new space station, Tiangong 1, is making a series of bright passes through the morning skies of North America. On Dec. 18th, Kevin Fetter of Brockville, Canada, caught the 8.5-metric-ton spaceship flying past the planet Mars (video):

Tiangong 1 is unoccupied now, but China is planning to send Taikonauts to visit the experimental station at least once and possibly twice in 2012. To prepare for their arrival, last Thursday automated systems onboard Tiangong 1 began a series of air quality checks inside the station's 15-cubic meter pressurized volume.

Tiangong 1 is currently about as bright as the stars of the Big Dipper (a value that will approximately double when future spacecraft dock with it). To see it, check Spaceweather's Simple Satellite Tracker or your cell phone for local flyby times.

Dec. 10th Total Lunar Eclipse Gallery

  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 19, 2011 there were 1272 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
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
49 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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