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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 383.0 km/sec
density: 0.8 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: B9
2259 UT Sep15
24-hr: B9
2259 UT Sep15
explanation | more data
Updated: Today at: 2259 UT
Daily Sun: 14 Sep 12
Solar activity is low. None of these sunspots are actively flaring. Credit: SDO/HMI
Sunspot number: 44
What is the sunspot number?
Updated 12 Sep 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 12 Sep 2012


The Radio Sun
10.7 cm flux: 105 sfu
explanation | more data
Updated 12 Sep 2012

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 2
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 4.8 nT
Bz: 1.0 nT north
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 12 Sep 12
A pair of coronal holes is emerging over the sun's eastern limb. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2012 Sep 15 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
10 %
10 %
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: 2012 Sep 15 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
30 %
10 %
MINOR
10 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
20 %
20 %
MINOR
30 %
20 %
SEVERE
30 %
10 %
 
Saturday, Sep. 15, 2012
What's up in space
 

They came from outer space--and you can have one! Genuine meteorites are now on sale in the Space Weather Store.

 
Own your own meteorite

MYSTERY SPHERES ON MARS: NASA's Mars rover Opportunity, still active after all these years, has just discovered a dense accumulation of puzzling little spheroids in a rock outcrop on the Red Planet. [full story]

MASSIVE SOLAR PROMINENCE: Today, a huge arc of plasma-filled magnetism is rising over the sun's western limb. "It's more than 30 Earth diameters long," says amateur astronomer John Stetson, who this morning photographed the structure backlit by the blue skies of Falmouth, Maine:

Here is what the prominence looks like through the telescopes of NASA's Solar Dynamics Observatory: image.

The size of the structure makes it an easy target for backyard solar telescopes. "Some prominences move at very high speed, but this one appears to be a relatively steady target for solar observers," says Stetson. "It is worth a look."

Realtime Space Weather Photo Gallery

NOT AURORAS: For the past week, solar wind has been buffeting Earth's magnetic field, turning skies around the Artic Circle beautiful shades of green. But not every green sky is caused by the aurora borealis. Last night, for example, pilot Brian Whittaker was flying 34,000 feet over the Atlantic Ocean when he witnessed verdant hues caused by a completely different phenomenon--airglow. Here is the picture he took from the cockpit window:

"A dark and moonless night away from all lights allowed a great view of this textured patch of airglow," says Whittaker. "The illumination was faint, but it could be seen especially in contrast to the dark ocean abyss below!"

Although airglow resembles the aurora borealis, its underlying physics is different. Airglow is caused by an assortment of chemical reactions in the upper atmosphere. During the day, ultraviolet radiation from the sun ionizes atoms and breaks apart molecules. At night, the atoms and molecules recombine, emitting photons as they return to normal. This process produces an aurora-like glow visible on very dark nights.

Because the Moon is new on Sept. 15th, tonight is a good night to spy this phenomenon. Get away from city lights, if you can, and take a look!

Realtime Aurora 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 September 15, 2012 there were 1329 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2012 QG42
Sep 14
7.4 LD
--
310 m
2012 QC8
Sep 14
22.7 LD
--
1.0 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
2007 PA8
Nov 5
16.8 LD
--
2.4 km
2010 JK1
Nov 25
9.3 LD
--
56 m
2009 LS
Nov 28
55.2 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.
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
Trade Show Displays
   
  more links...
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