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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 389.3 km/sec
density: 9.7 protons/cm3
explanation | more data
Updated: Today at 2335 UT
X-ray Solar Flares
6-hr max: C1
1734 UT Dec31
24-hr: M2
1315 UT Dec31
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 31 Dec 11
Sunspot 1389 poses a continued threat for M-class solar flares. Credit: SDO/HMI
Sunspot number: 104
What is the sunspot number?
Updated 30 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 30 Dec 2011


The Radio Sun
10.7 cm flux: 141 sfu
explanation | more data
Updated 30 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= 1
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 3.6 nT
Bz: 1.1 nT north
explanation | more data
Updated: Today at 2335 UT
Coronal Holes: 31 Dec 11
Solar wind flowing from this coronal hole will buffet Earth's magnetic field from now until ~Jan. 2. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Dec 31 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
40 %
40 %
CLASS X
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 31 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
10 %
10 %
MINOR
05 %
05 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
15 %
15 %
SEVERE
15 %
15 %
 
Saturday, Dec. 31, 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

METEORITE MYSTERY: Earth is mysteriously peppered with fragments of giant asteroid Vesta. (Here's a piece you can have for yourself.) New observations from NASA's Dawn spacecraft suggest an explanation involving one of the tallest mountains in the Solar System. Get the full story from Science@NASA.

SUDDEN IONOSPHERIC DISTURBANCE: Today around 1320 UT, a wave of ionization swept through the high atmosphere over Europe after sunspot AR1389 unleashed another M2-class solar flare. "There was a very clear sudden ionospheric disturbance on my VLF radio instruments," reports Rob Stammes, who sends these data from the Polar Light Center in Lofoten, Norway:

"The sun is below the horizon where we are located north of the Arctic Circle," says Stammes. "This event shows we still have some contact with the sun."

NOAA forecasters estimate a 40% chance of more M-flares during the next 24 hours. There is also a 5% chance of X-flares. Solar flare alerts: text, voice.

LAST AURORAS OF 2011? A minor solar wind stream is buffeting Earth's magnetic field with just enough force to ignite Northern Lights around the Arctic Circle. Hanneke Luijting of Tromsø, Norway, photographed the scene on Dec. 30th:

"It was amazing, I just sat there in the snow next to my tripod staring up into the sky, not believing my eyes!" says . "What a way to end 2011."

The show might not be over yet. There are still some hours left until 2012, and more auroras are possible as the solar wind continues to blow. Aurora alerts: text, voice.

more images: from Frank Olsen of Vesterålen, Norway; from Helge Mortensen of Brensholmen outside Tromsø; from Chad Blakley of Abisko National Park, Sweden; from Göran Strand of Aspås, Sweden; from P-M Hedén of Tänndalen, Sweden; from Beate Kiil Karlsen of Norway; from Andy Keen on the Finnish-Russian border

  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 31, 2011 there were 1272 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2011 SL102
Dec 28
75.9 LD
--
1.0 km
2011 WS95
Dec 28
7.1 LD
--
50 m
2011 YE29
Dec 29
7 LD
--
54 m
2011 YD29
Dec 30
6 LD
--
28 m
2011 YL28
Jan 4
3.7 LD
--
44 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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