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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 669.4 km/sec
density: 0.7 protons/cm3
explanation | more data
Updated: Today at 2342 UT
X-ray Solar Flares
6-hr max: C1
2047 UT Jul31
24-hr: C3
0254 UT Jul31
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 31 Jul 11
Sunspot 1261 has a delta-class magnetic field that harbors energy for X-class solar flares. Credit: SDO/HMI
Sunspot number: 101
What is the sunspot number?
Updated 30 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 30 Jul 2011


The Radio Sun
10.7 cm flux: 113 sfu
explanation | more data
Updated 30 Jul 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 3
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 5.2 nT
Bz: 1.6 nT north
explanation | more data
Updated: Today at 2344 UT
Coronal Holes: 31 Jul 11
Earth is inside a solar wind stream flowing from the indicated coronal hole. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Jul 31 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
45 %
45 %
CLASS X
05 %
05 %
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 31 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
35 %
15 %
MINOR
15 %
05 %
SEVERE
05 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
40 %
20 %
MINOR
20 %
10 %
SEVERE
10 %
01 %
 
Sunday, Jul. 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

WHAT LIES INSIDE JUPITER?The clouds of Jupiter hide many mysteries--from the roots of monster storms to possible stores of exotic matter. NASA's Juno spacecraft, scheduled to launch on August 5th, is going to find out what lies inside the giant planet. [full story] [video]

GEOMAGNETIC ACTIVITY: A solar wind stream is buffeting Earth's magnetic field and causing intermittent geomagnetic activity around the poles. The peak so far has been a G1-class storm that lasted for several hours around the end of July 30th. "I received a storm alert from Space Weather Phone," says Bob Johnson of Saskatoon Saskatchewan. "When I dashed outside, there were big-time auroras." He recorded the scene in this 25-second exposure:

NOAA forecasters estimate a ~20% chance of more such storms on July 31st as the solar wind continues to blow. High-latitude sky watchers should remain alert for auroras especially in the southern hemisphere where skies are winter-dark. Aurora alerts: text, voice.

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

SOLAR FLARE: Sunspot AR1261 unleashed a brief but powerful solar flare on July 30th at 0209 UT. Registering M9 on the Richter Scale of Flares, the blast almost crossed the threshold into X-territory (X-class flares are the most powerful kind). NASA's Solar Dynamics Observatory recorded the flare's extreme ultraviolet flash:

Because of its brevity, the eruption did not hurl a substantial cloud of material toward Earth. No CME is visible in SOHO coronagraphs. The eruption was not geoeffective, although future eruptions could be as the active region continues to turn toward Earth. Solar flare alerts: text, voice.

TODAY'S BONUS SHOTS: Hubble Transits Jupiter from Tom Harradine of Brisbane, Australia; Electric Blue Clouds from Tuomas Mäkynen of Hirvensalmi, Central Finland; Sunspot Sunset from Don Roberts of Wintersville, Ohio; Fireballs! from Yuichi Takasaka of British Columbia, Canada

BIG SUNSPOTS: The finest display of sunspots since 2006 is underway. Three behemoth sunspot groups are transiting the sun's northern hemisphere, shown here in a July 31st image from NASA's Solar Dynamics Observatory:

Among the three, sunspot 1261 is most active. The multi-cored group has a beta-gamma-delta class magnetic field that harbors energy for X-class solar flares. Readers with solar telescopes are encouraged to monitor developments.

more images: from Alan Friedman of Buffalo, NY; from Göran Strand of Froson, Sweden; from Michael Borman of Evansville, Indiana; from Neo of The Netherlands; from Ehsan Rostamizadeh of Kerman, Iran; from Steve Riegel of Albuquerque, NM;


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 July 31, 2011 there were 1237 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
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.
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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