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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 373.0 km/sec
density: 3.9 protons/cm3
explanation | more data
Updated: Today at 2343 UT
X-ray Solar Flares
6-hr max: B8
2113 UT Oct04
24-hr: C7
0923 UT Oct04
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 04 Oct 11
The solar disk is peppered with spots. None poses a significant threat for Earth-directed flares. Credit: SDO/HMI
Sunspot number: 85
What is the sunspot number?
Updated 03 Oct 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 Oct 2011


The Radio Sun
10.7 cm flux: 129 sfu
explanation | more data
Updated 03 Oct 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 2
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 4.5 nT
Bz: 1.6 nT north
explanation | more data
Updated: Today at 2345 UT
Coronal Holes: 04 Oct 11
There are no large coronal holes on the Earthside of the sun. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Oct 04 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
20 %
20 %
CLASS X
05 %
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 Oct 04 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
45 %
45 %
MINOR
20 %
25 %
SEVERE
05 %
05 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
45 %
45 %
MINOR
30 %
35 %
SEVERE
05 %
05 %
 
Tuesday, Oct. 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

TIANGONG-1 SIGHTINGS: China's first space station, an 8.5-ton experimental module named Tiangong-1 (Heavenly Palace-1), is flying over the United States this week. Last night, Justin Cowart saw it gliding over Carbondale, Illinois. "At first it was a little difficult to pick out in the moonlight, but the the space station became a little brighter as rose into the sky: image. I'd say it held a fairly steady magnitude of +1.5, with no large change in brightness." Readers, check Spaceweather's Satellite Tracker for sighting opportunities in your hometown. You can also turn your smartphone into a Tiangong-1 tracker by downloading the Simple Flybys app.

more images: from Jim Saueressig II of Burlington, Kansas

AURORA BOREALIS LANE: Globally, Earth's magnetic field has been quiet on Oct. 3rd and 4th. Nevertheless, last night Ronn Murray was able to see bright Northern Lights over Fairbanks, Alaska. He took a stroll down Aurora Borealis Lane:

"I love living in Fairbanks," says Murray. "The sky is so beautiful. I grabbed this shot on the way home from work."

Displays like this could spread around the Arctic Circle on Oct. 5th and 6th when one or more CMEs propelled by recent eruptions on the sun reach Earth. NOAA forecasters estimate a 30% chance of geomagnetic storms at high latitudes. Aurora alerts: text, voice.

September 2011 Aurora Gallery
[previous Septembers: 2010, 2009, 2008, 2007, 2006, 2005, 2004]

COMET AND CME: A comet discovered by amateur astronomers on Friday, Sept. 30th, disintegrated in spectacular fashion the very next day when it plunged into the sun. The Solar and Heliospheric Observatory recorded the comet's last hours. The end was punctuated by an unexpected explosion:

Watch the movie again. The timing of the CME so soon after the comet dove into the sun suggests a link. But what? There is no known mechanism for comets to trigger solar explosions. Before 2011 most solar physicists would have discounted the events of Oct. 1st as pure coincidence--and pure coincidence is still the most likely explanation. Earlier this year, however, the Solar Dynamics Observatory (SDO) watched another sungrazer disintegrate in the sun's atmosphere. On July 5, 2011, the unnamed comet appeared to interact with plasma and magnetic fields in its surroundings as it fell apart. Could a puny comet cause a magnetic instability that might propagate and blossom into a impressive CME? The question is not so crazy as it once seemed to be.

  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 October 4, 2011 there were 1250 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2011 SM173
Sep 30
0.8 LD
--
12 m
2011 TP
Oct 4
7.4 LD
--
23 m
2002 AG29
Oct 9
77.1 LD
--
1.0 km
2011 SE97
Oct 12
7.9 LD
--
50 m
2011 SS25
Oct 12
69.3 LD
--
1.1 km
2000 OJ8
Oct 13
49.8 LD
--
2.3 km
2009 TM8
Oct 17
0.9 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
1999 XP35
Dec 20
77.5 LD
--
1.0 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
 
Conquest Graphics
  for out-of-this-world printing and graphics
Trade Show Displays
   
  more links...
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