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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 539.7 km/sec
density: 0.7 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: B7
1729 UT Sep20
24-hr: C1
1140 UT Sep20
explanation | more data
Updated: Today at: 2259 UT
Daily Sun: 20 Sep 12
Solar activity is low despite the emergence of big new sunspot AR1575. Credit: SDO/HMI
Sunspot number: 62
What is the sunspot number?
Updated 20 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 20 Sep 2012


The Radio Sun
10.7 cm flux: 110 sfu
explanation | more data
Updated 20 Sep 2012

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 3
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 4.2 nT
Bz: 0.6 nT north
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.
SPACE WEATHER
NOAA Forecasts
Updated at: 2012 Sep 20 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
15 %
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: 2012 Sep 20 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
30 %
30 %
MINOR
05 %
05 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
35 %
35 %
MINOR
10 %
10 %
SEVERE
01 %
01 %
 
Thursday, Sep. 20, 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

CMEs MISS EARTH: The Solar and Heliospheric Observatory (SOHO) has observed at least three CMEs billowing away from the sun during the last 24 hours. However, none of the clouds are heading for Earth. The source of the explosions appears to be on the far side of the sun. Aurora alerts: text, voice.

AUTUMN LIGHTS: Northern autumn is only two days away--and that means it's aurora season. For reasons researchers don't fully understand, the days around equinoxes are the best times to see Northern Lights. Indeed, the Arctic Circle is glowing. Last night, Ole C. Salomonsen photographed the ongoing display from Tromsø, Norway:

"The sky was full of awesome auroras in magnifcent shapes and colors," says Salomonsen. "I also saw a magnificent blue fireball streaking through the lights above my favorite mountain Otertinden. It was the biggest fireball I have ever caught on camera. What a great photographic moment for me!"

More scenes like this are in the offing. 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. Aurora alerts: text, voice.

Realtime Aurora Photo Gallery

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


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 20, 2012 there were potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
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
--
88 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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