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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 579.6 km/sec
density: 3.3 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: C1
1747 UT Aug05
24-hr: C2
1246 UT Aug05
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 05 Aug 11
Sunspots 1261 and 1263 pose a continued threat for X-class solar flares. Credit: SDO/HMI
Sunspot number: 81
What is the sunspot number?
Updated 04 Aug 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 04 Aug 2011

The Radio Sun
10.7 cm flux: 116 sfu
explanation | more data
Updated 04 Aug 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 8 severe
24-hr max: Kp= 8
explanation | more data
Interplanetary Mag. Field
Btotal: 21.2 nT
Bz: 6.2 nT south
explanation | more data
Updated: Today at 2345 UT
Coronal Holes: 05 Aug 11
A minor solar wind stream flowing from the indicated coronal hole should reach Earth on Aug. 8-9. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Aug 05 2200 UTC
0-24 hr
24-48 hr
40 %
40 %
10 %
10 %
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 Aug 05 2200 UTC
0-24 hr
24-48 hr
20 %
25 %
40 %
15 %
35 %
05 %
High latitudes
0-24 hr
24-48 hr
20 %
25 %
35 %
20 %
40 %
15 %
Friday, Aug. 5, 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

GEOMAGNETIC STORM IN PROGRESS: A major geomagnetic storm is in progress following the impact of a CME on August 5th around 1800 UT. Sky watchers at all latitudes should be alert for auroras after nightfall. Tip: the best hours for aurora sightings are usually around local midnight. Aurora alerts: text, voice.

Analysts at the Goddard Space Weather Lab say that the CME impact may have strongly compressed Earth's magnetic field, directly exposing satellites in geosynchronous orbit to solar wind plasma. Stay tuned for updates on this aspect of the storm.

The arriving CME left the sun on August 4th, propelled by an M9.3-category eruption in the magnetic canopy of sunspot 1261. Click on the image to view a movie of the expanding cloud recorded by the Solar and Heliospheric Observatory:

Note: The many speckles in this movie are caused by energetic solar protons hitting the camera.

July 2011 Aurora Gallery
[previous Julys: 2010, 2009, 2008, 2007, 2006, 2005, 2004, 2003]

NIGHT-TIME SOLAR RADIO BURST: The M9-class solar flare of August 4th produced a burst of shortwave static so powerful that receivers on Earth picked it up after sunset. "A RadioJove observer in Florida recorded the burst when the sun was 38 degrees below the horizon," reports amateur radio astronomer Thomas Ashcraft. Ashcraft's own radio telescope in New Mexico recorded the event 1 hour and 54 minutes after sunset:

"To my knowledge, receptions like this are very rare," says Ashcraft.

Indeed they are. This event brings to mind the iconic night-time solar radio burst of March 8, 1958. Five radio telescopes at the University of Florida picked up emissions from the sun while observing the planet Jupiter in tthe middle of the night. On the other side of the world, radio astronomers in daylit Australia confirmed that a powerful solar radio burst had taken place at that exact time. The event is described in a 1959 Nature paper by pioneering radio astronomers Alex Smith and Tom Carr. They considered the possibility that solar radio waves might have been reflected by the Moon or carried to the night side of Earth by ionospheric ducting. In tthe end, they could not conclusively explain what happened and to this day night-time solar radio bursts remain a puzzle.

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

  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 August 5, 2011 there were 1241 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2007 DD
Jul 23
9.3 LD
31 m
2003 BK47
Jul 26
77.6 LD
1.1 km
2011 OD18
Jul 28
0.4 LD
22 m
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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