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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 506.4 km/sec
density: 0.7 protons/cm3
explanation | more data
Updated: Today at 2347 UT
X-ray Solar Flares
6-hr max: B2
2124 UT Aug20
24-hr: B6
0643 UT Aug20
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 18 Aug 12
None of the sunspots on the Earthside of the sun pose a threat for strong flares, but a potent farside active region is approaching from just behind the NE limb. Credit: SDO/HMI
Sunspot number: 69
What is the sunspot number?
Updated 18 Aug 2012

Spotless Days
Current Stretch: 0 days
2012 total: 0 days (0%)
2011 total: 2 days (<1%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 821 days
Typical Solar Min: 486 days

Update 18 Aug 2012

The Radio Sun
10.7 cm flux: 98 sfu
explanation | more data
Updated 18 Aug 2012

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 3
explanation | more data
Interplanetary Mag. Field
Btotal: 3.3 nT
Bz: 0.4 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 17 Aug 12
Earth is inside a stream of solar wind flowing from the indicated coronal hole. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2012 Aug 20 2200 UTC
0-24 hr
24-48 hr
15 %
15 %
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: 2012 Aug 20 2200 UTC
0-24 hr
24-48 hr
10 %
10 %
05 %
05 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
15 %
20 %
20 %
15 %
20 %
Monday, Aug. 20, 2012
What's up in space

Listen to radar echoes from satellites and meteors, live on listener-supported Space Weather Radio.

Spaceweather Radio is on the air

CURIOSITY ZAPS FIRST MARTIAN ROCK: A laser on Curiosity has fired for the first time on Mars, zapping a fist-size rock named "Coronation." Light reflected from the resulting plasma cloud reveals the rock's chemical make-up. In all, Coronation was hit by 30 pulses, each delivering more than a million watts of power for about 5 nano-seconds. [full story]

ARCTIC AURORA SEASON BEGINS: The long days of northern summer are coming to an end, and auroras are appearing in the darkening Arctic skies. "Yesterday I saw my first stars since last spring, and tonight the first auroras!" reports Fredrik Broms, who sends this picture from Kvaløya, Norway:

"It felt almost unreal to see them dancing across the light blue sky where only Jupiter, Venus and the brightest of the stars were visible," adds Broms. "I saw both green and red rays dancing over my head while standing barefoot in the grass - a somewhat unusual combination here in Tromsø! The return of the auroras was most welcome after a summer without any stars (save one)."

More arctic auroras are in the offing tonight as a high-speed solar wind stream buffets Earth's magnetic field. NOAA forecasters estimate a 25% to 30% chance of polar geomagnetic storms. Aurora alerts: text, phone.

Realtime Aurora Photo Gallery

RED SPRITES: High above Earth in the realm of meteors and noctilucent clouds, a strange and beautiful form of lightning dances at the edge of space. Researchers call the bolts "sprites"; they are red, fleeting, and tend to come in bunches. Jesper Grønne of Silkeborg, Denmark, photographed these specimens on August 15th:

"After several years of hunting sprites from my location in Denmark, I finally caught some last week--the first danish Red Sprites ever photographed," says Grønne. "They were located 50 km to 90 km above a thunderstorm some 350 km away over the North Sea. There were 2 flashes, each producing 5-6 individual Red Sprites."

"Sprites are a true space weather phenomenon," explains lightning scientist Oscar van der Velde of Sant Vicenç de Castellet, Spain. "They develop in mid-air around 80 km altitude, growing in both directions, first down, then up. This happens when a fierce lightning bolt draws lots of charge from a cloud near Earth's surface. Electric fields [shoot] to the top of Earth's atmosphere--and the result is a sprite. The entire process takes about 20 milliseconds."

Although sprites have been seen for at least a century, most scientists did not believe they existed until after 1989 when sprites were photographed by cameras onboard the space shuttle. Now "sprite chasers" routinely photograph sprites from their own homes. "I used an astro-modified Canon 5D II in video-mode to catch my sprites," says Grønne. Give it a try!

diagram: How to Look for Sprites (used with permission of

Realtime Space Weather Photo Gallery

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

  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 20, 2012 there were 1326 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
37655 Illapa
Aug 12
37 LD
1.2 km
2012 PZ17
Aug 12
3 LD
20 m
2012 PD20
Aug 18
9.7 LD
36 m
2000 ET70
Aug 21
58.5 LD
1.1 km
1998 TU3
Aug 25
49.2 LD
4.9 km
2009 AV
Aug 26
62.8 LD
1.1 km
2012 QC8
Sep 14
22.7 LD
1.1 km
1998 UO1
Oct 4
60.1 LD
2.1 km
2005 GQ21
Oct 12
77 LD
1.0 km
1998 ST49
Oct 18
28.7 LD
1.3 km
1991 VE
Oct 26
34 LD
1.1 km
2001 CV26
Oct 30
68 LD
2.4 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.
  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
Trade Show Displays
  more links...
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