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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 356.0 km/sec
density: 3.4 protons/cm3
explanation | more data
Updated: Today at 2343 UT
X-ray Solar Flares
6-hr max: C8
1930 UT Aug03
24-hr: M6
1348 UT Aug03
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 03 Aug 11
Sunspots 1261 and 1261 have "beta-gamma-delta" magnetic fields that harbor energy for X-class solar flares. Credit: SDO/HMI
Sunspot number: 98
What is the sunspot number?
Updated 02 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 02 Aug 2011

The Radio Sun
10.7 cm flux: 122 sfu
explanation | more data
Updated 02 Aug 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 1
explanation | more data
Interplanetary Mag. Field
Btotal: 3.0 nT
Bz: 1.5 nT south
explanation | more data
Updated: Today at 1901 UT
Coronal Holes: 03 Aug 11
A solar wind stream flowing from the indicated coronal hole should reach Earth on Aug. 7th or 8th. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Aug 03 2200 UTC
0-24 hr
24-48 hr
65 %
65 %
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 03 2200 UTC
0-24 hr
24-48 hr
05 %
40 %
01 %
10 %
01 %
05 %
High latitudes
0-24 hr
24-48 hr
05 %
40 %
01 %
15 %
01 %
05 %
Wednesday, Aug. 3, 2011
What's up in space

Turn your cell phone into a field-tested satellite tracker. Works for Android and iPhone.

Satellite flybys

M6-CLASS SOLAR FLARE: Sunspot 1261 unleashed another strong solar flare this morning--an M6-class flash at 1348 UT. Like yesterday's eruption from the same active region, this explosion propelled a CME in the general direction of Earth. ETA: August 5th. Stay tuned for additional analysis.

UPDATE: A listening station above the Arctic Circle in Norway reports ionospheric waves and VHF radio noise associated with today's M6-flare: their data.

INCOMING CLOUD: Yesterday's M1-class eruption from sunspot 1261 was observed by three spacecraft: SOHO, STEREO-A and STEREO-B. Using data from those three points of view, analysts at the GSFC Space Weather Lab have made a 3-dimensional model of the CME now en route to Earth. Click on the image to launch a computer-generated movie of the expanding cloud:

According to their work, the CME left the sun traveling 900 km/s and should reach Earth (denoted by a yellow dot in the simulation) on August 5th at 0300 UT plus or minus 7 hours. Another cloud produced by today's M-flare may be right behind it; stay tuned for movies of that one, too. Mild to moderate geomagnetic storms are possible when these CMEs arrive on August 5th and 6th. Aurora alerts: text, voice.

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

SPOTTED SUNSETS: During the recent years of deep solar minimum, observers of the sunset grew accustomed to a blank solar disk. News flash: The sunspots are back. "The sunset conditions of August 2nd were just right to show the massive sunspots AR1260, AR1261 and AR1263 to the casual observer who happened to glance at the sun for a brief few moments," reports Stephen W. Ramsden of Atlanta, Georgia. "You could even see the penumbra with the naked eye!" He had a camera handy and snapped this picture:

"The size and broiling movement of these sunspots just boggles the mind," he says. "You could fit every planet in the solar system with all of the known asteroids neatly inside the largest!"

Caution: Even when the sun is dimmed by low-hanging clouds or haze, focused sunlight can still damage your eyes. Do not look at the sun through unfiltered optics of any kind. A safely-filtered White Light Solar Observing System is the best way to monitor these great sunspots.

TODAY'S BONUS SHOTS: Flashing Solar Sail from Juha Peräsaari of Seinäjoki, Finland; Star-Grazing Comet from Gregg Ruppel of Ellisville, MO; Hot Heat! from Doug Zubenel of De Soto, Kansas; Electric Sunspots from C B Devgun SPACE of New Delhi, India;

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 3, 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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