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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 458.5 km/sec
density: 2.0 protons/cm3
explanation | more data
Updated: Today at 2343 UT
X-ray Solar Flares
6-hr max: M1
1907 UT Sep30
24-hr: M1
1907 UT Sep30
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 30 Sep 11
Sunspot 1302 has a "beta-gamma-delta" magnetic field that harbors energy for X-class solar flares. Credit: SDO/HMI
Sunspot number: 99
What is the sunspot number?
Updated 29 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 29 Sep 2011


The Radio Sun
10.7 cm flux: 137 sfu
explanation | more data
Updated 29 Sep 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 4 unsettled
24-hr max: Kp= 4
unsettled
explanation | more data
Interplanetary Mag. Field
Btotal: 4.9 nT
Bz: 2.6 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 30 Sep 11
Solar wind flowing from this minor coronal hole should reach Earth on ~Oct. 3rd. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Sep 30 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
60 %
60 %
CLASS X
20 %
20 %
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 30 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
20 %
20 %
MINOR
05 %
05 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
25 %
25 %
MINOR
05 %
05 %
SEVERE
01 %
01 %
 
Friday, Sep. 30, 2011
What's up in space
 

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

 
Satellite flybys

SUNDIVING COMET : This morning a quartet of amateur comet hunters (M. Kusiak, S. Liwo, B. Zhou and Z. Xu) independently noticed a comet in SOHO coronagraph images. The icy visitor from the icy solar system is diving toward the sun--probably a one-way trip. Kusiak expects the doomed comet to brighten to first magnitude between now and the early hours of Oct. 1st. [finder chart] [realtime images]

CHANCE OF FLARES: Sunspot 1302, quiet now for three days, still has a 'beta-gamma-delta' magnetic field that harbors energy for X-class flares. NOAA forecasters estimate a 30% chance of such eruptions today. X-flare alerts: text, voice.

SOLAR WIND BLASTS MERCURY: At a NASA teleconference yesterday, researchers working with data from the Messenger spacecraft offered new evidence that gusts of solar wind are penetrating Mercury's magnetic field and eroding material off the planet's surface. The spacecraft has actually flown through plumes of ionized sodium scoured from the surface and escaping from weak points in Mercury's magnetosphere. Click here and scroll down to "Presenter #4" for relevant data and images.

Another "scouring event" could be in the offing. The Solar and Heliospheric Observatory (SOHO) observed two farside CMEs on Sept 29th, and one of them is heading for the innermost planet:

Using observations from SOHO and the twin STEREO spacecraft, analysts at the Goddard Space Weather Lab have modeled the trajectory of these CMEs. The one on the left should hit Mercury on October 1st at 02:13 UT +/- 7 hours. Forewarned, mission scientists for the Messenger probe can be attentive to the CME's arrival and observe its effects on Mercury.

According to the CME's forecast track, the cloud will hit Venus later the same day. The ability to forecast CME impacts on other planets is a new development in space weather forecasting made possible by NASA's deployment of spacecraft around the full circumference of the sun. Stay tuned for more interplanetary forecasts here on spaceweather.com.

GREENLAND, GREEN SKY: At the apex of Greenland's ice sheet, more than 10,600 feet above sea level, arctic photographer Ed Stockard had a good view of this week's severe geomagnetic storm. On Sept. 27th the sky above the National Science Foundation's Summit Station where Stockard works turned almost completely green:

"The auroras were everywhere," he says. "We had clear skies and -37C temperatures. No matter which way you turned there was a great aurora. It was jaw dropping, talk to yourself amazement." (The "fat streak" among the star trails was Jupiter, he notes.)

On Sept. 29th, two nights after the storm peaked, auroras were still dancing around the Summit Station. Sky watchers in places like Greenland should remain alert for auroras as Earth's magnetic field remains unsettled. Aurora alerts: text, voice.

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

TODAY'S BONUS SHOTS: Dragonfly Sunset from Tavi Greiner of Ocean Isle Beach, NC; Sunspot Sunset from Heiko Ulbricht of Freital, Saxony, Germany; Magnetic Filaments from Malcolm Park of London, England, UK; Downtown Sunspots from Erik Rynearson of Los Angeles, California; Sunspot Mirage from Mila Zinkova of San Francisco, California

  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 30, 2011 there were 1250 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2011 SE58
Sep 27
0.6 LD
--
13 m
2011 SC108
Sep 27
1.2 LD
--
12 m
2011 SO5
Sep 29
5.5 LD
--
34 m
2011 SM173
Sep 30
0.8 LD
--
12 m
2002 AG29
Oct 9
77.1 LD
--
1.0 km
2011 SE97
Oct 12
7.9 LD
--
51 m
2011 SS25
Oct 12
69.6 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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