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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 379.0 km/sec
density: 9.6 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: C4
2024 UT Dec30
24-hr: M1
0309 UT Dec30
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 30 Dec 11
Sunspot 1389 is crackling with M-class solar flares. Credit: SDO/HMI
Sunspot number: 105
What is the sunspot number?
Updated 29 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 29 Dec 2011


The Radio Sun
10.7 cm flux: 147 sfu
explanation | more data
Updated 29 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= 2
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 4.4 nT
Bz: 0.7 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 30 Dec 11
Earth is entering a dense stream of solar wind flowing from the indicated coronal hole. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Dec 30 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 30 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
10 %
MINOR
01 %
05 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
10 %
15 %
SEVERE
05 %
15 %
 
Friday, Dec. 30, 2011
What's up in space
 

They came from outer space--and you can have one! Genuine meteorites are now on sale in the Space Weather Store.

 
Own your own meteorite

DECLINING CHANCE OF MAGNETIC STORMS: The CME expected on Dec. 29th either missed Earth or its impact was too weak to notice. Geomagnetic activity remains generally low with only a 20% chance of storms around the Arctic Circle during the next 24 hours.

ACTIVE SUNSPOT: New sunspot 1389 is crackling with M-class solar flares. NASA's Solar Dynamics Observatory recorded this extreme UV flash from the active region at 2151 UT on Dec. 29th:

Although the sunspot is not directly facing Earth, its flares can affect our planet. X-rays and UV radiation from yesterday's flares created waves of ionization in the upper atmosphere, altering the propagation of radio waves. The phenomenon was particularly strong over Europe where radio amateurs using low frequency receivers detected sudden ionospheric disturbances ("SIDs") above Ireland and Italy. Student groups who wish to detect solar flares in this way can ask about obtaining a SID monitor from Stanford University.

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

more images: from Michael Borman of Evansville, Indiana

MOTHER OF PEARL: As December draws to a close, the first polar stratospheric clouds (PSCs) of northern winter are forming around the Arctic Circle. Anders Gjørwad Hagen of Vinstra, Norway, photographed this specimen on Dec. 27th:

Also known as "nacreous" or "mother of pearl" clouds, icy PSCs form in the lower stratosphere when temperatures drop to around minus 85ºC. Sunlight shining through tiny ice particles ~10µm across produce the characteristic bright iridescent colors by diffraction and interference.

The display Hagen witnessed formed in the wake of "Dagmar," a storm that "hit the coast of Norway with hurricane strength on Dec. 25th and 26th," says Hagen. "Record breaking winds up to 145 mph were recorded. While people on the coast dealt with the aftermath, photo enthusiasts inland saw the effects of high altitude winds in these colorful clouds. It was a beautiful display, but not comfortable to think of all the suffering lying behind it."

more images: from Bjarki Mikkelsen of Jokkmokk Lapland, Sweden; from P-M Hedén of Tänndalen, Sweden; from Krystian Rosa of Brandbu, Norway; from Patricia Cowern of Porjus,Sweden

  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 30, 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 YX15
Dec 27
8.3 LD
--
36 m
2011 SL102
Dec 28
75.9 LD
--
1.0 km
2011 WS95
Dec 28
7.1 LD
--
50 m
2011 YL28
Jan 4
3.7 LD
--
41 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
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  more links...
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