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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 400.8 km/sec
density: 0.0 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: B3
2241 UT Apr15
24-hr: C2
0142 UT Apr15
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 15 Apr 12
Sunspot AR1458 is crackling with C-class solar flares. This, plus the emergence of AR1459, could signal an uptick in solar activity. Credit: SDO/HMI
Sunspot number: 65
What is the sunspot number?
Updated 14 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 14 Apr 2012

The Radio Sun
10.7 cm flux: 98 sfu
explanation | more data
Updated 14 Apr 2012

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 2
explanation | more data
Interplanetary Mag. Field
Btotal: 2.2 nT
Bz: 0.2 nT south
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 15 Apr 12
There are no large coronal holes on tthe Earthside of the sun. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2012 Apr 15 2200 UTC
0-24 hr
24-48 hr
10 %
10 %
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 15 2200 UTC
0-24 hr
24-48 hr
10 %
10 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
15 %
01 %
01 %
01 %
01 %
Sunday, Apr. 15, 2012
What's up in space

Thirty-five new items have just been added to our Meteorite Jewelry collection. Browse the Space Weather Store for something out of this world.

Meteorite jewelry

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]

SOMETHING IN THE OFFING: A potentially significant active region is about to rotate onto the Earthside of the sun. A hot plume of plasma flying over the sun's northeastern limb heralded its approach during the early hours of April 15th:

Extreme UV image credit: NASA's Solar Dynamics Observatory

The eruption hurled a coronal mass ejection toward NASA's STEREO-B spacecraft. Analysts at the Goddard Space Weather Lab have prepared a forecast track showing the progress of the cloud. No planets are in the line of fire.

Stay tuned for updates as the sun turns to reveal the active region in the days ahead. Solar flare alerts: text, phone.

SATURN'S RINGS AT THEIR BEST: On Sunday, April 15th, Saturn is at opposition--directly opposite the sun in the skies of Earth. The ringed planet rises at sunset and soars high in the sky at midnight, up all night long. This is the time when Saturn's rings are at their best. From the point of view of Earth, shadows in the ring plane almost completely disappear (just as your own shadow tries to hide beneath your feet at noon) and sunlight is directly backscattered by icy ring particles toward our planet.

Amateur astronomer Christopher Go photographed the brightening rings on April 12th:

"Saturn is close to opposition and the rings are brightening. This is the Seeliger Effect," says Go. "Also a Northern Electrostatic Disturbance, which was detected by Cassini a few days ago, can be seen as a white patch north of the green belt."

Saturn is easy to find. Look south at midnight. The ringed planet forms a "double star" with Spica. [sky map]

more images: from Efrain Morales Rivera of Aguadilla, Puerto Rico

WEEKEND AURORAS: For the third day in a row, a high-speed solar wind stream is buffeting Earth's magnetic field. On Saturday, April 14th, an intense burst of auroras appeared over Bodø, Norway:

"The lights went from nothing to extreme in a very short time," says photographer Sindre Nedrevåg. "The background was pretty, too: There was Venus and a lot of stars, together with the colours of the sunset. The auroras became so intense that even 3 seconds of exposure wasn't fast enough with my Nikon D300s at ISO 640."

NOAA forecasters estimate a 10% to 15% chance of more geomagnetic activity during the next 24 hours as the solar wind continues to blow.

more images: from Sylvain Serre of Ivujivik, Nunavik, Quebec, Canada; from Einar Halvorsrud of Alta, Norway; from Yuri Gnatyuk of Arkhangelsk, Russia; from Gregory Lacy of the Yukon River north of Fairbanks, Alaska; from Jónína Óskarsdóttir of Faskrudsfjordur, Iceland; from Eric Fokke of Norway, Lofoten; from Brian Tomlinson of Reykjavik Iceland; from B.Art Braafhart of Salla, Finnish Lapland;

  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 15, 2012 there were 1287 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
1996 SK
Apr 18
67.2 LD
1.6 km
2007 HV4
Apr 19
4.8 LD
8 m
2012 GP1
Apr 21
9 LD
26 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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