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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 259.9 km/sec
density: 2.0 protons/cm3
explanation | more data
Updated: Today at 2347 UT
X-ray Solar Flares
6-hr max: C3
2255 UT Dec17
24-hr: C3
2255 UT Dec17
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 17 Dec 11
None of these sunspots poses a threat for strong flares. Solar activity is low. Credit: SDO/HMI
Sunspot number: 60
What is the sunspot number?
Updated 16 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 16 Dec 2011


The Radio Sun
10.7 cm flux: 121 sfu
explanation | more data
Updated 16 Dec 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 0
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 2.2 nT
Bz: 0.3 nT south
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 17 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 17 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
01 %
01 %
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 17 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
05 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
10 %
20 %
SEVERE
05 %
10 %
 
Saturday, Dec. 17, 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

QUIET SUN: Solar activity is very low. WIth no sunspots producing strong flares, the sun's x-ray output has flatlined. Significant flares are unlikely this weekend.

CONTINUED ADVENTURES OF COMET LOVEJOY: The scorched core of sungrazing Comet Lovejoy is still intact as it recedes from the sun. Even the comet's flamboyant tail, temporarily lost in transit through the solar corona, has regrown. Click to view the last 24 hours of coronagraph images from the Solar and Heliospheric Observatory (SOHO):

SOHO images show two tails: the ion tail and the dust tail. The ion tail is made of gas and is blown directly away from the sun by the solar wind. The heavier dust tail is curved and more closely traces the comet's orbit.

Now that the comet is more than five degrees from the sun, it is possible (albeit still not easy) for amateur astronomers to photograph it just before sunrise. A team led by Czech astronomer Jan Ebr captured this image at sunrise on Dec. 17th:


Credit: Jakub Cerny, Jan Ebr, Martin Jelinek, Petr Kubanek, Michael Prouza, Michal Ringes

"We used a remotely-controlled 12-inch telescope in Malargue, Argentina," says Ebr. "The sun was below horizon at the time we took the picture, but just barely. There was only a 30 minute window between the rise of the comet and that of the sun "

COMET LOVEJOY SURVIVES: Incredibly, sungrazing Comet Lovejoy survived its close encounter with the sun yesterday. Lovejoy flew only 140,000 km over the stellar surface during the early hours of Dec. 16th. Experts expected the icy sundiver to be destroyed. Instead, NASA's Solar Dynamics Observatory caught the comet emerging from perihelion (closest approach) apparently intact:


Movie formats: 25 MB Quicktime, 0.8 MB m4v

SDO also recorded Comet Lovejoy's entry into the sun's atmosphere: movie.

Comet Lovejoy began the week as a chunk of dusty, rocky ice more than 200 meters in diameter. No one can say how much of the comet's core remains intact or how long it will hang together after the searing heat of perihelion. "There is still a possibility that Comet Lovejoy will start to fragment," says researcher Karl Battams in a NASA news release. "It’s been through a tremendously traumatic event; structurally, it could be extremely weak."

CURIOSITY AND THE SOLAR STORM: Last month, a massive solar storm launched itself toward Mars just as NASA's new rover, Curiosity, was blasting off from Cape Canaveral in the same direction. Researchers say it was a welcome coincidence. For the first time in Mars-rover history, Curiosity is equipped to study solar storms, and it will be monitoring space weather all the way to the Red Planet. [full story]


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 17, 2011 there were 1272 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
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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