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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 675.1 km/sec
density: 2.3 protons/cm3
explanation | more data
Updated: Today at 2342 UT
X-ray Solar Flares
6-hr max: C4
1701 UT Sep26
24-hr: M4
0508 UT Sep26
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 26 Sep 11
Sunspot 1302 poses a continued threat for X-class solar flares. Credit: SDO/HMI
Sunspot number: 108
What is the sunspot number?
Updated 25 Sep 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 25 Sep 2011

The Radio Sun
10.7 cm flux: 190 sfu
explanation | more data
Updated 25 Sep 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 8 severe
24-hr max: Kp= 8
explanation | more data
Interplanetary Mag. Field
Btotal: 8.8 nT
Bz: 2.7 nT north
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 26 Sep 11
A solar wind stream flowing from the indicated coronal hole could reach Earth on Sept. 30th-Oct. 1st. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Sep 26 2200 UTC
0-24 hr
24-48 hr
80 %
40 %
40 %
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 Sep 26 2200 UTC
0-24 hr
24-48 hr
30 %
15 %
15 %
05 %
05 %
01 %
High latitudes
0-24 hr
24-48 hr
35 %
20 %
10 %
10 %
05 %
01 %
Monday, Sep. 26, 2011
What's up in space

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

Satellite flybys

GEOMAGNETIC STORM: A strong-to-severe geomagnetic storm is in progress following the impact of a coronal mass ejection (CME) at approximately 12:15 UT on Sept. 26th. The Goddard Space Weather Lab reports a "strong compression of Earth's magnetosphere. Simulations indicate that solar wind plasma [has penetrated] close to geosynchronous orbit starting at 13:00UT." Geosynchronous satellites could therefore be directly exposed to solar wind plasma and magnetic fields. High-latitude sky watchers should be alert for Northern and Southern Lights after nightfall. Aurora alerts: text, voice.

aurora photos: from Minoru Yoneto of Queenstown, New Zealand; from Ole Ambrosiussen of Hvinningdal, Silkeborg, Denmark; from Steven Graham of Christchurch, New Zealand; from Mika Puurula of Sotkamo, Finland; from Jonathan Tucker of Whitehorse, Yukon; from Julius Jahre Sætre of Vestfold, Norway

STRONG SOLAR ACTIVITY: Having already unleashed two X-flares since Sept. 22nd, sunspot AR1302 appears ready for more. The active region has a complex "beta-gamma-delta" magnetic field that harbors energy for strong M- and X-class eruptions. Flares from AR1302 will become increasingly geoeffective as the sunspot turns toward Earth in the days ahead.

On Sunday, Sept. 25th, Dutch astrophotographer Emil Kraaikamp took a magnificent picture of the active region, which is so big only half of it fits on the screen. Click to view the entire sunspot:

"This is how the sunspot looked through my solar-filtered 10-inch Newtonian telescope," says Kraaikamp. "Due to the always-variable daytime seeing here in the Netherlands, it took a couple of hours to finally capture one good set of images, but it was well worth the effort to get this view of the huge sunspot formation."

more images: from Andy Devey of Barnsley South Yorkshire; from Alan Friedman of Buffalo, NY; from Monika Landy-Gyebnar of Balatonfured, Hungary; from Piet Berger of Simpelveld, Netherlands; from Howard Eskildsen of Ocala, Florida; from Dzmitry Kananovich of Tallinn, Estonia; from Chris Schur of Payson, Az; from John Stetson of Falmouth, Maine; from Grenier of Paris France; from Maximilian Teodorescu of Magurele, Romania; from Cai-Uso Wohler of Bispingen, Germany; from Philippe Van den Doorn of Rixensart, Belgium; ;

SOLAR STATIC: Active sunspot 1302 has turned the sun into a shortwave radio transmitter. Shock waves rippling from the sunspot's exploding magnetic canopy are exciting plasma oscillations in the sun's atmosphere. The result: Bursts of static are issuing from the loudspeakers of shortwave radios on Earth. Amateur radio astronomer Thomas Ashcraft recorded this sample from his backyard observatory in New Mexico on Sept. 24th:

Dynamic spectrum: The horizontal axis is time (h:m:s), the vertical axis is frequency (MHz). Image credit: Wes Greenman

"Saturday was a super-strong solar day with near continuous flaring and radio sweeps," says Ashcraft. "The sound file (above) corresponds to an M3 flare at 1918 UTC. It was the strongest radio sweep of the observing day."

"Try listening to the radio bursts in stereo," he advises. "I was recording on two separate radios at 21.1 MHz and 21.9 MHz, and I put each one into its own channel of the audio file. This gives a spatial dimension as the bursts sweep down in frequency."

September 2011 Aurora Gallery
[previous Septembers: 2010, 2009, 2008, 2007, 2006, 2005, 2004]

  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 September 26, 2011 there were 1250 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2011 SQ32
Sep 20
7.5 LD
44 m
2011 SK68
Sep 21
5.8 LD
13 m
2007 TD
Sep 22
6.2 LD
58 m
2011 SE58
Sep 27
0.6 LD
13 m
2011 SO5
Sep 29
5.6 LD
34 m
2002 AG29
Oct 9
77.1 LD
1.0 km
2011 SS25
Oct 12
70.4 LD
1.2 km
2000 OJ8
Oct 13
49.8 LD
2.4 km
2009 TM8
Oct 17
0.9 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.
  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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