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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 454.3 km/sec
density: 0.1 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: C1
1653 UT Apr07
24-hr: C1
0436 UT Apr07
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 07 Apr 11
New sunspot 1186 poses a threat for C-class solar flares. Credit: SDO/HMI
Sunspot number: 56
What is the sunspot number?
Updated 06 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 06 Apr 2011

The Radio Sun
10.7 cm flux: 117 sfu
explanation | more data
Updated 06 Apr 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 3
explanation | more data
Interplanetary Mag. Field
Btotal: 3.0 nT
Bz: 0.4 nT north
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 06 Apr 11
A solar wind stream flowing from the indicated coronal hole could brush against Earth's magnetic field on April 10th or 11th. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Apr 07 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 07 2200 UTC
0-24 hr
24-48 hr
15 %
10 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
20 %
15 %
01 %
01 %
01 %
01 %
Thursday, Apr. 7, 2011
What's up in space

Metallic photos of the sun by renowned photographer Greg Piepol bring together the best of art and science. Buy one or a whole set. They make a stellar gift.

Metallic pictures of the Sun

RIPPING FIREBALL: "There was a rippingly fine fireball over north central New Mexico on April 5th at 01:50 am MDT," reports amateur radio astronomer Thomas Ashcraft. "Signals from distant radio stations bounced off the meteor's trail as it shredded the ionosphere. Here is a movie I made with the radio echo in stereo at two frequencies. The full radio reflection lasted more than two minutes." [NASA video: Spring is Fireball Season]

more fireballs: from Marsha Adams of Sedona, Arizona

STEADY SKIES OVER JAPAN: Only a few hours before a new and powerful earthquake shook Japan on April 7th, amateur astronomer Mitsuo Muraoka of Hatoyama, Saitama, photographed a conjunction of the crescent Moon and the Pleiades:

"It was a beautiful sight," says Muraoka. "Only a little while later, however, [I might have had trouble steadying my camera]."

According to the Japan Meteorological Agency, a 7.4 magnitude aftershock of the March 11th super-quake struck offshore at 11:30 pm Japan time. Remarkably, no serious damage to the island nation has been reported, and a significant tsunami is not expected. Astronomers there can return their attention to the sky, which remained steady throughout.

more moonshots: from Doug Zubenel at the St. Philippine Duchesne Memorial Park, Linn County, Kansas; from Rafael Schmall of Kaposfo, Somogy, Hungary; from Alfredo Garcia Jr of Lomita, CA; from Monika Landy-Gyebnar of Veszprem, Hungary

TORMENTED FILAMENT: A filament of magnetism and hot plasma is twisting and turning around the sun's southeastern limb today. Click on the image to launch a 2-day movie from NASA's Solar Dynamics Observatory. Warning: The mpeg file contains 49 megabytes of data, but it is worth the wait to download:

The filament's magnetic backbone stretches more than 300,000 km from end to end. As suggested by events in the movie, this vast tormented structure is unstable and could erupt at any moment. Any such blast would probably not be Earth-directed because of the filament's location on the limb. Stay tuned.

more images: from Karzaman Ahmad of Langkawi National Observatory, Malaysia; from Philippe Roucheux of Joigny, Bourgogne, France; from Theo Ramakers of Social Circle, Georgia; from Z. Parsons-West and J. Stetson of South Portland, Maine; from Howard Eskildsen of Ocala, Florida; from Oscar Martín Mesonero of Madrid, Spain

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 7, 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
25 m
2011 FT53
Apr 9
6 LD
34 m
2011 GE
Apr 13
4.8 LD
26 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
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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