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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 338.3 km/sec
density: 0.4 protons/cm3
explanation | more data
Updated: Today at 2343 UT
X-ray Solar Flares
6-hr max: B4
1948 UT Aug31
24-hr: C2
1124 UT Aug31
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 31 Aug 11
Sunspots are emerging at several locations around the solar disk. New sunspot 1282, in particular, could pose a threat for Earth-directed C-flares. Credit: SDO/HMI
Sunspot number: 89
What is the sunspot number?
Updated 30 Aug 2011

Spotless Days
Current Stretch: 0 days
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 30 Aug 2011


The Radio Sun
10.7 cm flux: 105 sfu
explanation | more data
Updated 30 Aug 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 1
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 2.3 nT
Bz: 0.4 nT south
explanation | more data
Updated: Today at 2344 UT
Coronal Holes: 30 Aug 11
Earth is inside a solar wind stream flowing from the indicated coronal hole. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Aug 31 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
15 %
15 %
CLASS X
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 Aug 31 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
10 %
10 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
 
Wednesday, Aug. 31, 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

JUNO PHOTOGRAPHS EARTH-MOON SYSTEM: NASA's Juno spacecraft, en route to Jupiter, has turned and photographed the Earth-Moon system from a dustance of million miles. "This is a remarkable sight people get to see all too rarely," says Scott Bolton, Juno principal investigator from the Southwest Research Institute in San Antonio. Nasa.gov has the full story.

EMERGING SUNSPOTS: Sunspots are emerging at several locations around the solar disk, peppering the Earth-side of the sun with active regions. Of particular interest is fast-growing sunspot 1282, shown here in an August 31st snapshot from NASA's Solar Dynamics Observatory:

AR1282 has increased in size more than ten-fold during the past 48 hours: movie. Moreover, the sunspot is near the center of the solar disk, so any flares from this active region today would likely be Earth-directed.

SO MUCH FOR DOOMSDAY: Comet Elenin (C/2010 X1), widely known for inaccurate reports of its threat to Earth, appears to be breaking apart. Observations by amateur astronomer Michael Mattiazzo of Castlemaine, Australia show a marked dimming and elongation of the comet's nucleus over a ten day period:

The behavior of Comet Elenin is akin to that of Comet LINEAR (C/1999 S4), which disintegrated when it approached the sun in back in 2000. Mattiazzo witnessed that event, too. "Yes I did observe the breakup of C/1999 S4 in July 2000," he recalls. "It was quite spectacular watching the nucleus spread out into a cigar shape over a period of days. The apparent breakup of C/2010 X1 is similar, although less visually spectacular."

Comets are fragile objects, easily disrupted by solar heat. As a result, the possible breakup of Comet Elenin, while unexpected, comes as no surprise. Readers with pertinent images are invited to submit them here.


August 2011 Aurora Gallery
[previous Augusts: 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 August 31, 2011 there were 1241 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
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
1994 CK1
Nov 16
68.8 LD
--
1.5 km
1996 FG3
Nov 23
39.5 LD
--
1.1 km
2003 WM7
Dec 9
47.6 LD
--
1.5 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.
STEREO
  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
Heliophysics
  the underlying science of space weather
Science Central
 
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