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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 390.9 km/sec
density: 15.2 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: B4
1700 UT Sep19
24-hr: C2
1512 UT Sep19
explanation | more data
Updated: Today at: 2259 UT
Daily Sun: 19 Sep 12
Solar activity is low despite the emergence of big new sunspot AR1579. Credit: SDO/HMI
Sunspot number: 61
What is the sunspot number?
Updated 19 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 19 Sep 2012

The Radio Sun
10.7 cm flux: 104 sfu
explanation | more data
Updated 19 Sep 2012

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 4 unsettled
24-hr max: Kp= 4
explanation | more data
Interplanetary Mag. Field
Btotal: 10.3 nT
Bz: 7.6 nT south
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 19 Sep 12
A solar wind stream flowing from the indicated coronal hole should reach Earth on Sept 22-23. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2012 Sep 19 2200 UTC
0-24 hr
24-48 hr
10 %
10 %
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 19 2200 UTC
0-24 hr
24-48 hr
15 %
25 %
05 %
05 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
20 %
30 %
30 %
25 %
30 %
Wednesday, Sep. 19, 2012
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

CRESCENT MOON AND MARS: Looking for Mars? Tonight the Red Planet is easy to find less than 2o from the crescent Moon. Look for the pair shining side-by-side in the western sky after sunset. Sky map. Images: #1.

DISAPPEARING ASTEROID: More than a week after amateur astronomers witnessed an explosion in the cloudtops of Jupiter more powerful than an atomic bomb, no debris has appeared at the blast site. "I took a picture of Jupiter on Sept. 15th using the same telescope that I used to observe the brilliant fireball flash above Jupiter's clouds on the morning of Sept. 10th," reports Dan Petersen of Racine, Wisconsin, the man who saw the explosion first. "This photo shows that five days after the explosion there was still no signature debris cloud near 'ground zero.'"

The absense of debris suggests that the source of the explosion, probably an asteroid, was small. Studies show that Jupiter is a frequent target for 10-meter class space rock, and this is almost certainly another example of Jupiter getting hit. The giant planet absorbed the explosion and swallowed the remains of the asteroid whole.

Realtime Space Weather Photo Gallery

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 on Sept. 17th:

"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 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 19, 2012 there were 1330 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
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.
  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
Trade Show Displays
  more links...
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