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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 314.5 km/sec
density: 0.4 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: C4
1753 UT Sep25
24-hr: C4
1753 UT Sep25
explanation | more data
Updated: Today at: 2259 UT
Daily Sun: 25 Sep 12
Sunspot 1575 poses a slight threat for M-class solar flares. Credit: SDO/HMI
Sunspot number: 90
What is the sunspot number?
Updated 25 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 25 Sep 2012


The Radio Sun
10.7 cm flux: 137 sfu
explanation | more data
Updated 25 Sep 2012

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 1
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 5.7 nT
Bz: 5.4 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 25 Sep 12
There are no large coronal holes on the Earth side of the sun. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2012 Sep 25 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
20 %
20 %
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 25 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
05 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
10 %
10 %
SEVERE
05 %
05 %
 
Tuesday, Sep. 25, 2012
What's up in space
 

Listen to radar echoes from satellites and meteors, live on listener-supported Space Weather Radio.

 
Spaceweather Radio is on the air

QUIET SUN : Solar activity is low with only a slight (15%) chance of M-class solar flares during the next 24 hours. Solar flare alerts: text, voice.

BIG SUN-DIVING COMET DISCOVERED: Astronomy forums are buzzing with speculation about newly-discovered Comet C/2012 S1 (ISON). Currently located beyond the orbit of Jupiter, Comet ISON is heading for a very close encounter with the sun next year. In Nov. 2013, it will pass less than 0.012 AU (1.8 million km) from the solar surface. The fierce heating it experiences then could turn the comet into a bright naked-eye object. (continued below)


Comet ISON photographed by E. Guido, G. Sostero & N. Howes on Sept. 24. [more]

Much about this comet--and its ultimate fate--remains unknown. "At this stage we're just throwing darts at the board," says Karl Battams of the NASA-supported Sungrazer Comet Project, who lays out two possibilities:

"In the best case, the comet is big, bright, and skirts the sun next November. It would be extremely bright -- negative magnitudes maybe -- and naked-eye visible for observers in the Northern Hemisphere for at least a couple of months."

"Alternately, comets can and often do fizzle out! Comet Elenin springs to mind as a recent example, but there are more famous examples of comets that got the astronomy community seriously worked up, only to fizzle. This is quite possibly a 'new' comet coming in from the Oort cloud, meaning this could be its first-ever encounter with the Sun. If so, with all those icy volatiles intact and never having been truly stressed (thermally and gravitationally), the comet could well disrupt and dissipate weeks or months before reaching the sun."

"Either of the above scenarios is possible, as is anything in between," Battams says. "There's no doubt that Comet ISON will be closely watched. Because the comet is so far away, however, our knowledge probably won't develop much for at least a few more months."

Meanwhile, noted comet researcher John Bortle has pointed out a curious similarity between the orbit of Comet ISON and that of the Great Comet of 1680. "Purely as speculation," he says, "perhaps the two bodies could have been one a few revolutions ago."

Stay tuned for updates.

Realtime Space Weather Photo Gallery

AUTUMN LIGHTS: The onset of northern autumn means it's aurora season. For reasons researchers don't fully understand, equinoxes are the best times to see Northern Lights. And, right on cue, the Arctic Circle is glowing. Marianne Bergli sends this picture of auroras shimmering directly above Storfjord, Norway:

"Last night it was difficult to select [which part of the sky to photograph]. The auroras were dancing everywhere," says Bergli. "Eventually I was just lying on my back looking up. It was absolutely, unbelievable wonderful."

As the week begins, the solar wind velocity is low (~350 km/s), but at this time of year it only takes a gentle gust to ignite bright auroras around the Arctic Circle. 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 25, 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
--
38 m
2012 RK15
Sep 24
8.2 LD
--
88 m
2012 SL50
Sep 27
2.8 LD
--
23 m
2012 SY49
Sep 28
2.6 LD
--
31 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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