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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 579.7 km/sec
density: 0.6 protons/cm3
explanation | more data
Updated: Today at 2338 UT
X-ray Solar Flares
6-hr max: B9
1758 UT Apr12
24-hr: C3
0607 UT Apr12
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 12 Apr 11
New sunspot 1190 is growing rapidly. Also, an un-numbered sunspot is emerging at the circled location. The potential for flares is increasing with the sunspot count. Credit: SDO/HMI

more images: from Emil Kraaikamp of Ruinerwold, The Netherlands
Sunspot number: 80
What is the sunspot number?
Updated 11 Apr 2011

Spotless Days
Current Stretch: 0 days
2011 total: 1 day (<1%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 820 days
Typical Solar Min: 486 days

Updated 11 Apr 2011

The Radio Sun
10.7 cm flux: 106 sfu
explanation | more data
Updated 11 Apr 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 5
explanation | more data
Interplanetary Mag. Field
Btotal: 6.8 nT
Bz: 1.5 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 12 Apr 11
Earth is inside a solar wind stream flowing from the indicated coronal hole. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Apr 12 2200 UTC
0-24 hr
24-48 hr
05 %
05 %
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 Apr 12 2200 UTC
0-24 hr
24-48 hr
20 %
10 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
25 %
15 %
01 %
01 %
01 %
01 %
Tuesday, Apr. 12, 2011
What's up in space

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

Satellite flybys

EVIDENCE OF IMPACT: For billions of years, the Earth and Moon have been pummeled by meteoroids. On the Moon, evidence of the onslaught is visible to the naked eye in the form of innumerable craters. On Earth, however, most craters have been weathered away. Looking around, you might never guess we live in a cosmic shooting gallery. Nevertheless, the evidence exists: "Impactites," for instance, are shock-melted pieces of our own planet found scattered around impact sites, while "tektites" are glassy fragments of the impactors themselves. Meteorite hunter Dr. Mike Reynolds has scoured the planet for authentic fragments of major impacts and he's offering them to the general public. Click here for details.

GEOMAGNETIC STORM: A G1-class geomagnetic storm is in progress, sparked by a high-speed solar wind stream which is buffeting Earth's magnetic field. High latitude sky watchers should be alert for auroras.

Shawn Malone sends this picture, taken before sunrise on April 12th, from Marquette, Michigan:

"I coaxed myself out of bed around 4am and was rewarded by a lightshow!" says Malone. "The auroras had no problem shining through the light pollution. I think the sun IS waking up. I watched the Northern Lights until the sunlight wiped them out."

more images: from Warren Gammel of Fairbanks, Alaska; from Doug Kiesling of Saint Cloud, MN

NOAA forecasters estimate a 25% chance of more geomagnetic activity during the next 24 hours. Aurora alerts: voice, text.

April 2011 Aurora Gallery
[previous Aprils: 2010, 2009, 2008, 2007, 2006, 2005, 2004, 2003, 2002]

SOLAR NEPHELOCOCCYGIA: It's a noun. Nephelococcygia: The act of seeking and finding shapes in clouds. On April 10th in Selsey, UK, Pete Lawrence set up his solar telescope and performed nephelococcygia on the sun. "I think I found a fish," he says.

The fish-shaped form at the base of the image is a cloud of plasma held above the stellar surface by magnetic fields. It looks dark because it is cooler than the inferno below. Readers with solar telescopes are encouraged to monitor this fishy form--and learn to pronounce nephelococcygia.

UPDATE: The fish is gone. As sometimes happens to sea creatures on the sun, it erupted. Amateur astronomer Michael Buxton of Ocean Beach, California, filmed the event. The movie is not as gruesome as it sounds.

more images: from Karzaman Ahmad of Langkawi National Observatory, Malaysia; from Steve Riegel of Albuquerque, NM; from N. Pommeville and J. Stetson of South Portland, Maine

April 2011 Aurora Gallery
[previous Aprils: 2010, 2009, 2008, 2007, 2006, 2005, 2004, 2003, 2002]

  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 12, 2011 there were 1214 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2011 GW9
Apr 6
0.5 LD
10 m
2011 GP28
Apr 6
0.2 LD
6 m
2011 FT29
Apr 7
6.3 LD
38 m
2011 GZ2
Apr 8
2.7 LD
26 m
2011 FT53
Apr 9
6 LD
34 m
2011 GE
Apr 13
4.8 LD
28 m
2011 GP59
Apr 15
1.4 LD
60 m
2002 DB4
Apr 15
62.5 LD
2.2 km
2011 GJ3
Apr 27
7.7 LD
24 m
2008 UC202
Apr 27
8.9 LD
10 m
2009 UK20
May 2
8.6 LD
23 m
2008 FU6
May 5
75.5 LD
1.2 km
2003 YT1
May 5
65.3 LD
2.5 km
2002 JC
Jun 1
57.5 LD
1.6 km
2009 BD
Jun 2
0.9 LD
9 m
2002 JB9
Jun 11
71.5 LD
3.2 km
2001 VH75
Jun 12
42.2 LD
1.1 km
2004 LO2
Jun 15
9.9 LD
48 m
2001 QP181
Jul 2
35.1 LD
1.0 km
2011 GA55
Jul 6
62.9 LD
1.0 km
2003 YS117
Jul 14
73.9 LD
1.0 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
Conquest Graphics
  for out-of-this-world printing and graphics
Science Central
  more links...
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