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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 295.7 km/sec
density: 1.7 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: B4
2058 UT Dec16
24-hr: B5
0820 UT Dec16
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 16 Dec 11
None of these sunspots poses a threat for strong flares. Credit: SDO/HMI
Sunspot number: 44
What is the sunspot number?
Updated 15 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 15 Dec 2011


The Radio Sun
10.7 cm flux: 124 sfu
explanation | more data
Updated 15 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: 0.5 nT
Bz: 0.3 nT south
explanation | more data
Updated: Today at 2345 UT
Coronal Holes: 15 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 16 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 16 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 %
10 %
SEVERE
05 %
05 %
 
Friday, Dec. 16, 2011
What's up in space
 

Turn your cell phone into a field-tested satellite tracker. Works for Android and iPhone.

 
Satellite flybys

COMET LOVEJOY SURVIVES: Incredibly, sungrazing Comet Lovejoy has survived its close encounter with the sun. 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."

New images received on Dec. 16th from the Solar and Heliospheric Observatory confirm that Comet Lovejoy survived perihelion and show the comet receding from the sun:

At first the emerging comet was missing its tail. This might have been a trick of geometry: The comet's tail was pointing away from Earth, temporarily invisible due to foreshortening. On the other hand, the absence might have been genuine. The comet's store of surface volatile materials could have been "baked-out" by the fiery transit, leaving the nucleus unable to mount substantial jets of gas and dust. Newly-arriving SOHO images show the tail is reforming.

There could be more surprises in store for this unpredictable comet. Stay tuned for updates.

More data: Europe's Proba2 microsatellite recorded Comet Lovejoy's entrance and exit from the sun: movie. The darkening in the middle of the movie is a solar eclipse: "Proba2's orbit briefly carried it behind the earth with respect to the sun," explains Dan Seaton of the Royal Observatory of Belgium. "The timing of the eclipse was perfect. It happened while the comet was out of sight behind the sun."

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 16, 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
7.2 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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