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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 326.3 km/sec
density: 0.7 protons/cm3
explanation | more data
Updated: Today at 2343 UT
X-ray Solar Flares
6-hr max: M5
2036 UT Sep24
24-hr: X1
0940 UT Sep24
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 24 Sep 11
Sunspot 1302 poses a threat for X-class solar flares. Credit: SDO/HMI
Sunspot number: 90
What is the sunspot number?
Updated 23 Sep 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 23 Sep 2011


The Radio Sun
10.7 cm flux: 158 sfu
explanation | more data
Updated 23 Sep 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: 4.7 nT
Bz: 1.8 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 24 Sep 11
There are no large coronal holes on the Earth-facing side of the sun. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Sep 24 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
80 %
80 %
CLASS X
40 %
40 %
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 Sep 24 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
40 %
10 %
MINOR
30 %
50 %
SEVERE
01 %
30 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
40 %
10 %
MINOR
30 %
60 %
SEVERE
01 %
30 %
 
Saturday, Sep. 24, 2011
What's up in space
 

Turn your cell phone into a field-tested satellite tracker. Works for Android and iPhone.

 
Satellite flybys

UARS UPDATE: NASA's bus-sized UARS satellite returned to Earth sometime between 11:23 p.m. EDT on Sept. 23rd and 1:09 a.m. EDT on Sept. 24th. There are still no credible visual reports of the fireball. At a post-reentry teleconference, NASA officials showed a map of the possible re-entry track. UARS could have come down at any point along the green line, which crosses vast regions of the Pacific Ocean, North America, north Atlantic Ocean, Africa, and southern Indian Ocean. Odds favor an ocean landing, but no one knows the exact location of UARS debris.

SATURDAY X-FLARE: Behemoth sunspot 1302 unleashed another strong flare on Saturday morning--an X1.9-category blast at 0940 UT. NASA's Solar Dynamics Observatory recorded the extreme ultraviolet flash:

The movie also shows a shadowy shock wave racing away from the blast site. This is a sign that the blast produced a coronal mass ejection (CME). Analysts at the Goddard Space Weather Lab say the CME could deliver a glancing blow to Earth's magnetic field on Sept. 26 at 14:10 UT (+/- 7 hours); click here for an animated forecast track.

UPDATE: Sunspot AR1302 followed today's X2-flare with an M7-flare nearly as strong (movie). So far none of the blasts has been squarely Earth-directed, but this could change as the sunspot turns toward our planet in the days ahead. AR1302 is growing and shows no immediate signs of quieting down. Solar flare alerts: text, voice.

ACTIVE SUNSPOT: New sunspot 1302 has already produced two X-flares (X1.4 on Sept. 22nd and X1.9 on Sept. 24th), can another be far behind? NOAA forecasters put the 24-hour probability at 20%. The sheer size of the active region suggests the odds might be even higher than that:

Each of the dark cores in this snapshot from the Solar Dynamics Observatory is larger than Earth, and the entire active region stretches more than 100,000 km from end to end. The sunspot's magnetic field is crackling with sub-X-class flares that could grow into a larger eruption as the sunspot continues to turn toward Earth. Solar flare alerts: text, voice.

more images: from Pavol Rapavy of Observatory Rimavska Sobota, Slovakia; from Cai-Uso Wohler of Bispingen, Germany; from Jo Dahlmans of Ulestraten The Netherlands; from P-M Hedén of Ålbo, Sweden; from Howard Eskildsen of Ocala, Florida


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

  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 24, 2011 there were 1250 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2003 QC10
Sep 18
50 LD
--
1.2 km
2004 SV55
Sep 19
67.5 LD
--
1.2 km
2011 SQ32
Sep 20
7.5 LD
--
44 m
2007 TD
Sep 22
6.2 LD
--
58 m
2011 SO5
Sep 29
5.6 LD
--
34 m
2002 AG29
Oct 9
77.1 LD
--
1.0 km
2011 SS25
Oct 13
70.2 LD
--
1.2 km
2000 OJ8
Oct 13
49.8 LD
--
2.4 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
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
 
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