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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 310.4 km/sec
density: 0.4 protons/cm3
explanation | more data
Updated: Today at 2342 UT
X-ray Solar Flares
6-hr max: B2
2058 UT Apr11
24-hr: B2
1030 UT Apr11
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 11 Apr 12
A new sunspot is growing at the circled location. Credit: SDO/HMI
Sunspot number: 24
What is the sunspot number?
Updated 10 Apr 2012

Spotless Days
Current Stretch: 0 days
2012 total: 0 days (0%)
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 10 Apr 2012

The Radio Sun
10.7 cm flux: 93 sfu
explanation | more data
Updated 10 Apr 2012

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 2
explanation | more data
Interplanetary Mag. Field
Btotal: 6.1 nT
Bz: 5.7 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 11 Apr 12
Solar wind flowing from this coronal hole should reach Earth on April 13-14. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2012 Apr 11 2200 UTC
0-24 hr
24-48 hr
01 %
01 %
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: 2012 Apr 11 2200 UTC
0-24 hr
24-48 hr
25 %
30 %
05 %
10 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
40 %
40 %
20 %
20 %
10 %
10 %
Wednesday, Apr. 11, 2012
What's up in space

Listen to radar echoes from satellites and meteors, live on listener-supported Space Weather Radio.

Spaceweather Radio is on the air

LYRID METEOR SHOWER: Earth is approaching the debris field of ancient Comet Thatcher, source of the annual Lyrid meteor shower. Forecasters expect the shower to peak on April 21-22; a nearly-new moon on those dates will provide perfect dark-sky conditions for meteor watching. Usually the shower is mild (10-20 meteors per hour) but unmapped filaments of dust in the comet's tail sometimes trigger outbursts 10 times stronger. [video] [Lyrid chat] [more]

NO CME, NO PROBLEM: A CME expected to hit Earth on April 9th missed, but the Arctic lit up with auroras anyway. Yuichi Takasaka sends this report from the Northwest Territories of Canada: "Even though the CME missed, we had three outbreaks of Northern Lights at Prelude Lake." Here is one of them:

The source of the display was the IMF (interplanetary magnetic field), which tipped south on April 9th, opening a crack in Earth's magnetosphere. Solar wind poured in and fueled the auroras.

More Arctic lights are possible on April 13-14 when a high speed solar wind stream is expected to hit Earth's magnetic field. NOAA forecasters estimate a 20% chance of geomagnetic storms around the poles. Aurora alerts: text, phone.

more images: from Frank Olsen of Blokken in Sortland, Norway; from Ole C. Salomonsen of Tromsø, Norway; from Anne Fyhn of Grøtfjord, Tromsø, Norway; from Harald Albrigtsen of Grøtfjorden, Norway; from Sylvain Serre of Ivujivik, Nunavik, Quebec, Canada; from Göran Strand of Rörvattnet, Sweden;

SEVEN ICE HALOES: As spring unfolds, Arctic daylight will soon wrap all the way around the clock, chasing away midnight displays of aurora borealis. There are compensations, however, for 24-hour sunlight. It increases the odds of witnessing ice haloes around the sun. On April 4th, Fredrik Broms photographed this display over Rovaniemi, Finland

"Looking up at the sky during daytime can be rewarding," says Broms. "In the cold crisp air in Finland a beautiful ice halo display was visible a few days ago."

The luminous rays, rings, and arcs he photographed are caused by sunlight shining through ice crystals in the air. Looking carefully, Broms counted at least seven distinct ice halos around the sun: labeled image.

You don't have to be in the Arctic to witness displays like this. Temperatures are freezing all around the world in clouds ~10km above the ground. Sunlight shining through icy clouds can produce haloes anywhere. Browse the links for more examples: from Ivo Dinsbergs of Riga, Latvia; from Heiko Ulbricht of Freital, Saxony, Germany.

  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 April 11, 2012 there were 1287 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2012 GD
Apr 10
9.4 LD
18 m
1996 SK
Apr 18
67.2 LD
1.6 km
2007 HV4
Apr 19
4.8 LD
8 m
2011 WV134
Apr 28
38.6 LD
1.6 km
1992 JD
May 2
9.5 LD
43 m
2010 KK37
May 19
2.3 LD
31 m
4183 Cuno
May 20
47.4 LD
5.7 km
2002 VX94
May 26
72.8 LD
1.1 km
2002 AC
Jun 16
62.2 LD
1.2 km
1999 BJ8
Jun 16
68.8 LD
1.1 km
2005 GO21
Jun 21
17.1 LD
2.2 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.
  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
  the underlying science of space weather
Trade Show Displays
  more links...
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