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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 417.4 km/sec
density: 0.1 protons/cm3
explanation | more data
Updated: Today at 2340 UT
X-ray Solar Flares
6-hr max: C2
1736 UT Sep03
24-hr: C2
1736 UT Sep03
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 03 Sep 11
The sun is peppered with sunspot groups, but flare activity remains low. Credit: SDO/HMI
Sunspot number: 103
What is the sunspot number?
Updated 02 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 02 Sep 2011

The Radio Sun
10.7 cm flux: 115 sfu
explanation | more data
Updated 02 Sep 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 3 quiet
24-hr max: Kp= 3
explanation | more data
Interplanetary Mag. Field
Btotal: 7.9 nT
Bz: 1.1 nT north
explanation | more data
Updated: Today at 2345 UT
Coronal Holes: 03 Sep 11
A solar wind stream flowing from the indicated coronal hole could reach Earth on Sept. 5-7. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Sep 03 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: 2011 Sep 03 2200 UTC
0-24 hr
24-48 hr
20 %
15 %
05 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
25 %
20 %
10 %
05 %
01 %
01 %
Saturday, Sep. 3, 2011
What's up in space

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

Satellite flybys

VISIT TO PLUTO: Dwarf planet Pluto is a world of mystery waiting to be visited for the first time. NASA's New Horizons probe is racing across the solar system for a close encounter that could dramatically alter what researchers "know" about Pluto and other small worlds. [story] [video] [artist's concept]

WEEKEND AURORAS: " I can tell that this aurora season is going to be mind-blowing," says photographer Brandon Lovett of Fairbanks, Alaska. "Night has completely returned to Fairbanks, and the aurora borealis has come out to take the place of the midnight sun." He took this picture on Sept. 3rd:


"The night began with scattered clouds and only a hint of the display taking place behind them," he says. "As the clouds cleared the aurora showed itself in full force. In a matter of seconds a thin glowing strip exploded into a display of pink and green dancing curtains. The ground matched the sky, casting shadows of my tripod and myself. It was spectacular to say the very least. All images are in un-retouched jpeg form."

more images: from Fredrik Broms of Kvaløya, Norway; from Helge Mortensen of Rekvik outside Tromsø, Norway; from Frank Olsen of Tromsø, Norway

A COMET AMONG THE STARS: As September begins, green Comet Garradd (C/2009 P1) is gliding across the star fields of the Milky Way. Tonight it will pass by Brocchi's Cluster, also known as "the Coathanger." Italian astronomer Rolando Ligustri photographed the approach on Sept. 2nd using a remotely-controlled 20" telescope in New Mexico:

"Comets are such beautiful objects," says Ligustri. "With the Milky Way as a backdrop, there seems to be a nice photo-op for Comet Garradd every night."

For now Comet Garradd is a telescopic object. It is, however, approaching the sun and brightening. Recent projections place it at peak magnitude 6, on the threshold of naked-eye visibility, in February 2012. Because Comet Garradd is a first-time visitor to the inner solar system, it could behave in unexpected ways, perhaps exceeding those expectations. Stay tuned--and meanwhile browse the image links below.

more images: from John Chumack of Yellow Springs, Ohio; from Kosma Coronaios of Louis Trichardt, Limpopo Province, South Africa; from Günther Strauch of Borken, NRW, Germany; from Parks Squyres of SaddleBrooke, Arizona; from Chris Schur of Payson, Arizona; from Tamas Abraham of Zsambek, Hungary; from Efrain Morales Rivera of Aguadilla, Puerto Rico;

finder charts: from Sky and Telescope, from Seiichi Yoshida

August 2011 Aurora Gallery
[previous Augusts: 2010, 2009, 2008, 2007, 2006, 2005, 2004, 2003, 2002]

  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 3, 2011 there were 1244 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2011 QD50
Aug 27
8.7 LD
79 m
2011 QF48
Aug 27
3.4 LD
37 m
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
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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