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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 353.0 km/sec
density: 3.5 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: C6
2250 UT Dec20
24-hr: C6
2250 UT Dec20
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 20 Dec 11
New sunspots are emerging over the sun's NE limb. Nevertheless, solar activity remains low. Credit: SDO/HMI
Sunspot number: 133
What is the sunspot number?
Updated 19 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 19 Dec 2011


The Radio Sun
10.7 cm flux: 128 sfu
explanation | more data
Updated 19 Dec 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 1
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 7.9 nT
Bz: 2.4 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 20 Dec 11
There are no large coronal holes on the Earthside of the sun. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Dec 20 2240 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
05 %
05 %
CLASS X
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 20 2240 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
01 %
01 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
10 %
10 %
SEVERE
05 %
05 %
 
Tuesday, Dec. 20, 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."

UPDATE: This morning in New Zealand, Minoru Yoneto photographed the ghostly tail of Comet Lovejoy shining through the twilight:

"I couldn't see the comet with my naked eye, but a 1.3 sec exposure with my Canon Kiss X2 digital camera revealed Lovejoy's long tail."

In the clearer skies of Devonport, Tasmania, amateur astronomer Peter Sayers did see the tail with his unaided eyes--"but just barely," he says. "The tail was just naked-eye and perhaps a degree long in our Tasmanian summer early morning twilight." [image]

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]

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 20, 2011 there were 1272 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2011 YQ1
Dec 14
1 LD
--
33 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
--
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.
STEREO
  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
Heliophysics
  the underlying science of space weather
Science Central
Trade Show Displays
   
  more links...
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