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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 365.8 km/sec
density: 0.7 protons/cm3
explanation | more data
Updated: Today at 2347 UT
X-ray Solar Flares
6-hr max: C1
1701 UT Aug04
24-hr: C3
1500 UT Aug04
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 04 Aug 12
The sun is peppered with spots, but none poses a threat for strong solar flares. Credit: SDO/HMI
Sunspot number: 160
What is the sunspot number?
Updated 03 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

Updated 03 Aug 2012

The Radio Sun
10.7 cm flux: 135 sfu
explanation | more data
Updated 03 Aug 2012

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 2
explanation | more data
Interplanetary Mag. Field
Btotal: 3.1 nT
Bz: 1.8 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 04 Aug 12
There are no large coronal holes on the Earthside of the sun. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2012 Aug 04 2200 UTC
0-24 hr
24-48 hr
20 %
20 %
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 04 2200 UTC
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
15 %
15 %
15 %
05 %
05 %
Saturday, Aug. 4, 2012
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

WATCH OUT FOR THE MARTIAN TRIANGLE: When the sun goes down tonight, step outside and look southwest. Mars, Saturn and the blue-giant star Spica have converged to form a 1st-magnitude triangle not far above the horizon. The eye-catching arangement makes it easy to find the Red Planet on the eve of the Mars Landing. [full story] [video]

ERUPTING MAGNETIC FILAMENT: A filament of magnetism connecting sunspots AR1538 and AR1540 rose up and erupted on August 4th. Look for the extreme UV glow of hot plasma in this movie recorded by NASA's Solar Dynamics Observatory:

As the filament ripped through the sun's atmosphere, it propelled a massive CME into space: movie. The expanding cloud does not appear to be on a collision course with Earth, although a glancing blow might be possible 2 to 3 days hence. Stay tuned for further analysis.

FLYING SAUCERS: On August 1st, Ken Rotberg observed a pair of rainbow-colored saucers over Delray Beach, Florida --but they weren't UFOs. The technical term is pileus clouds:

Atmospheric optics expert Les Cowley explains how they form: "On sunny afternoons, cumulus clouds boil upwards, pushing layers of moist air above them even higher where they cool and condense to form cloud caps or 'pileus' (Latin for cap). When pileus clouds form very quickly, their water droplets tend to be all the same size--the perfect condition for iridescent colors."

"I noticed the sun dropping behind a huge storm cloud in the west and ['the saucers' appeared]," says Rotberg. "I was just amazed at what I was witnessing, watching it slowly change. There was nobody near me at the time to share it with!" Consider it shared.

Realtime Space Weather Photo Gallery

RIPPING PERSEID: As Earth enters a broad stream of debris from Comet Swift-Tuttle, more and more Perseid meteors are appearing in the night sky. "Last night, I captured a Perseid fireball ripping through the ionosphere over New Mexico," reports amateur astronomer Thomas Ashcraft. "It was traveling pretty fast - 133,000 miles per hour!" Click to see and hear the meteoroid disintegrate:

The movie's sound track comes from Ashcraft's dual-frequency meteor radar. It works like this: Radio signals from distant VHF transmitters bounce off the meteor's ion trail. Ashcraft's antennas can pick up those reflections, which sound like ghostly echoes in the loudspeaker of his VHF receiver.

At the moment, Perseid meteor rates are low--no more than about 10 per hour. In the days ahead, however, Earth will plunge deeper into the comet's debris stream, and meteor activity will increase accordingly. Forecasters expect the shower to peak on August 12-13 with as many as 100+ meteors per hour visible from dark-sky sites. Stay tuned for Perseids.

Realtime Meteor 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 4, 2012 there were 1324 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2012 OQ
Jul 24
7.7 LD
190 m
2012 OU1
Jul 25
8.5 LD
54 m
37655 Illapa
Aug 12
37 LD
1.2 km
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
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
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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