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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 658.0 km/sec
density: 1.5 protons/cm3
explanation | more data
Updated: Today at 2343 UT
X-ray Solar Flares
6-hr max: B2
1745 UT Jul21
24-hr: B3
0454 UT Jul21
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 21 Jul 11
None of these sunspots poses an immediate threat for strong flares. Solar activity remains low. Credit: SDO/HMI
Sunspot number: 79
What is the sunspot number?
Updated 20 Jul 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 20 Jul 2011

The Radio Sun
10.7 cm flux: 100 sfu
explanation | more data
Updated 20 Jul 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 3 quiet
24-hr max: Kp= 3
explanation | more data
Interplanetary Mag. Field
Btotal: 2.3 nT
Bz: 0.3 nT south
explanation | more data
Updated: Today at 2345 UT
Coronal Holes: 21 Jul 11
Earth is inside a solar wind stream flowing from the indicated coronal hole. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Jul 21 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: 2011 Jul 21 2200 UTC
0-24 hr
24-48 hr
40 %
30 %
30 %
10 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
50 %
40 %
40 %
30 %
10 %
05 %
Thursday, Jul. 21, 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

PLUTO'S NEW MOON: Astronomers using the Hubble Space Telescope have discovered a fourth moon orbiting Pluto. The new satellite popped up in a Hubble survey searching for rings around the dwarf planet. Science@NASA has the full story.

LAST PICTURE OF ATLANTIS IN SPACE: This morning, space shuttle Atlantis landed at NASA's Kennedy Space Center, wrapping up the final mission of NASA's space shuttle program. At 08:27:48 UT, just 21 minutes before the deorbit burn, astrophotographer Thierry Legault captured what might be the last picture of Atlantis in space--and it was a solar transit:

Above: Space shuttle Atlantis (circled) and sunspot AR1254

Because Atlantis was passing over Europe in broad daylight, the only way to catch it would be in silhouette against the sun. "I traveled from my home in Paris, France, to Emden city, Germany, to put myself in the transit's path," says Legault. "Skies were cloudy, but fortunately the transit occurred in a clear gap. Its duration was only 0.9 seconds and Atlantis, from a distance of 566 km (350 miles), appeared on four images."

Readers, do you have a picture of Atlantis in space taken after 08:27:48 UT on July 21st? If so, submit your images here.

more images: from Christopher Handler of Mt Lofty, South Australia, Australia; from Wim Filmalter of Riversdale, Western Cape Province, South Africa; from Rob Carew of Melbourne, Australia; from Rudie Loots of Somerset West, South Africa; from Mike C of Prairieville, LA;

HOT DINNER: Paleontologist and amateur astronomer Wienie van der Oord lives in the Arava desert in Israel, close to the Jordanian and Egyptian border. "A friend and I were hiking in the area before sunset on July 16th when I realized we hadn't eaten since breakfast," says van der Oord. It was time for a hot dinner:

"Anna tried to prevent me from burning my mouth as I took a bite out of the sun," continues van der Oord. "The meal was not as filling as I expected, so later I had the Moon for desert."

Other photographers are also finding the sun to be an appetizing target. Click on the links for more snapshots: from Tom of Derby, Western Australia; from Matthias Juergens of Gnevsdorf, Germany; from Peter Desypris of Island of Syros, Greece; from Michael Borman of Evansville, Indiana;

2011 Noctilucent Cloud Gallery
[previous years: 2003, 2004, 2005, 2006, 2007, 2008, 2009]

June 2011 Aurora Gallery
[Aurora alerts: text, voice] [previous Junes: 2010, 2008, 2001]

  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 July 21, 2011 there were 1237 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2003 YS117
Jul 14
73.9 LD
1.0 km
2007 DD
Jul 23
9.3 LD
31 m
2003 BK47
Jul 26
77.6 LD
1.1 km
2009 AV
Aug 22
49.7 LD
1.1 km
2003 QC10
Sep 18
50 LD
1.2 km
2004 SV55
Sep 19
67.5 LD
1.2 km
2007 TD
Sep 23
3.8 LD
58 m
2002 AG29
Oct 9
77.1 LD
1.0 km
2000 OJ8
Oct 13
49.8 LD
2.5 km
2009 TM8
Oct 17
1.1 LD
8 m
2011 FZ2
Nov 7
75.9 LD
1.6 km
2005 YU55
Nov 8
0.8 LD
175 m
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
Science Central
Conquest Graphics
  for out-of-this-world printing and graphics
Trade Show Displays
  more links...
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