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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 384.7 km/sec
density: 2.5 protons/cm3
explanation | more data
Updated: Today at 2347 UT
X-ray Solar Flares
6-hr max: B3
2127 UT Sep18
24-hr: C1
1009 UT Sep18
explanation | more data
Updated: Today at: 2259 UT
Daily Sun: 18 Sep 12
A new sunspot (circled) emerging over the sun's NE limb increases the chances of flares in the days ahead. Credit: SDO/HMI
Sunspot number: 51
What is the sunspot number?
Updated 18 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 18 Sep 2012


The Radio Sun
10.7 cm flux: 102 sfu
explanation | more data
Updated 18 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= 3
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 6.4 nT
Bz: 3.5 nT south
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 18 Sep 12
Solar wind flowing from these three coronal holes will buffet Earth's magnetic field, one after another, from Sept. 18th through Sept. 22nd. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2012 Sep 18 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 18 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
05 %
05 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
30 %
30 %
SEVERE
25 %
25 %
 
Tuesday, Sep. 18, 2012
What's up in space
 

Hang the Transit of Venus on your wall! Hubble-quality images from NASA's Solar Dynamics Observatory are now available as metallic posters in the Space Weather Store.

 
Venus Transit metal posters

CRESCENT MOON: Tonight, the crescent Moon is passing almost directly between Mars and Saturn. A good view of the western horizon is required to see the crossing. If you have one, go outside just after sunnset and take a look. Sky maps: Sept. 18, 19. Images: #1.

INCOMING ACTIVE REGIONS: Solar activity has been low for more than a week. This could change in the days ahead as a pair of active regions rotates onto the Earthside of the sun. NASA's Solar Dynamics Observatory recorded the signs of their approach during the early hours of Sept. 18th:

Pictured above are the magnetic canopies of sunspots. Plasma-filled magnetic loops towering more than 50,000 km above the sun's eastern limb herald the approach of the active regions, possibly turning a pair of flare centers toward Earth as the week unfolds. Amateur astronomers witth backyard solar telescopes should train their optics on the eastern limb; solar activity is in the offing. Solar flare alerts: text, voice.

AUTUMN LIGHTS: Northern autumn is only days away, and that means aurora season is underway. For reasons researchers don't fully understand, equinoxes are the best times to see Northern Lights. The show is well underway at Summit Station, an NSF-sponsored research facility on top of the Greenland ice sheet, where Ed Stockard snapped this photo last night:

"The auroras came on fast and furious, moving and dancing across the entire sky," says Stockard. "Aurora season has definitely begun on top of the ice sheet. Bring on the lights! Tonight's temperature was - 35F with five knots of wind.... time to dress for the space weather."

NOAA forecasters estimate a 25% to 30% chance of strong polar geomagnetic storms for the next three nights as a series of solar wind streams gently buffet Earth's magnetic field. High latitude sky watchers should remain alert for auroras. Aurora alerts: text, voice.

Realtime Aurora Photo Gallery


Realtime Space Weather 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 18, 2012 there were potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2012 QC8
Sep 14
22.7 LD
--
1.0 km
2012 SW2
Sep 19
1.8 LD
--
14 m
2012 SZ2
Sep 19
8.2 LD
--
39 m
2012 RK15
Sep 24
8.2 LD
--
93 m
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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