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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 400.6 km/sec
density: 1.8 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: C1
1948 UT Sep04
24-hr: M3
1145 UT Sep04
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 04 Sep 11
Departing sunspot group 1280 unleashed an M3-class solar flare on Sept. 4th. Credit: SDO/HMI
Sunspot number: 139
What is the sunspot number?
Updated 03 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 03 Sep 2011


The Radio Sun
10.7 cm flux: 119 sfu
explanation | more data
Updated 03 Sep 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 3 quiet
24-hr max: Kp= 3
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 5.2 nT
Bz: 2.9 nT north
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 04 Sep 11
A minor solar wind stream flowing from the indicated coronal hole could reach Earth on Sept. 5-7. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Sep 04 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
25 %
15 %
CLASS X
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 04 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
10 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
20 %
15 %
MINOR
05 %
01 %
SEVERE
01 %
01 %
 
Sunday, Sep. 4, 2011
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

SOLAR FLARE: This morning at 1145 UT, an active region on the sun's western limb unleashed an M3-class solar flare. NASA's Solar Dynamics Observatory recorded the flash of extreme UV radiation:

Although the blast site was not directly facing Earth, radiation from the explosion nevertheless ionized Earth's upper atmosphere. This altered the propagation of radio signals around Europe, where it was high-noon at the time of the flare. "I detected a sharp change in signal levels from two radio stations on the VLF band," reports Rob Stammes of Lofoten, Norway.

In addition to the UV flash, the explosion also hurled a CME into space: SOHO movie. The cloud is not heading for Earth, so no auroras will result from this particular event. That's not to say, however, that no auroras are in the offing. Read on....

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 Northern Lights are possible on Sept 5th - 7th in response to the expected arrival of a minor solar wind stream. Arctic sky watchers should remain alert for auroras.

more images: from Chad Blakley of Abisko National Park, Sweden; from Bernt Olsen of Ersfjord, Troms, Norway; from B.Art Braafhart of Salla-Sallatunturi, Finnish Lapland; from Sylvain Serre of Ivujivik, Quebec, Canada; from Fredrik Broms of Kvaløya, Norway; from Helge Mortensen of Rekvik outside Tromsø, Norway; from Frank Olsen of Tromsø, Norway;

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 4, 2011 there were 1244 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2011 QD50
Aug 27
8.7 LD
--
73 m
2011 QF48
Aug 27
3.4 LD
--
38 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.
STEREO
  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
Heliophysics
  the underlying science of space weather
Science Central
 
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