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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 357.0 km/sec
density: 1.0 protons/cm3
explanation | more data
Updated: Today at 2343 UT
X-ray Solar Flares
6-hr max: C1
2232 UT Oct20
24-hr: M1
0325 UT Oct20
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 20 Oct 11
Sunspots 1324 and 1319 pose a threat for M-class solar flares. Credit: SDO/HMI
Sunspot number: 162
What is the sunspot number?
Updated 18 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 18 Oct 2011


The Radio Sun
10.7 cm flux: 153 sfu
explanation | more data
Updated 18 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: 3.8 nT
Bz: 1.2 nT south
explanation | more data
Updated: Today at 2344 UT
Coronal Holes: 19 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 20 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
60 %
60 %
CLASS X
05 %
05 %
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 20 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
05 %
05 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
 
Thursday, Oct. 20, 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

WEEKEND METEOR SHOWER: Earth is about to pass through a stream of debris from Halley's comet, source of the annual Orionid meteor shower. Forecasters expect the shower to peak on Saturday morning, Oct. 22nd, with more than 15 meteors per hour. Earth isn't the only world in the debris stream; NASA researchers will also be watching for meteoroid strikes on the Moon. [full story] [meteor radar]

SOLAR FLARE: This morning at 0325 UT, Earth-orbiting satellites detected an M1.6-class solar flare, the first significant eruption in days. Because the blast site was located on the sun's northwestern limb, the flare was not Earth-directed. Solar flare alerts: text, phone.

THE DECAY OF ROSAT: The doomed ROSAT X-ray space telescope continues to descend toward Earth. Multiple experts agree that re-entry should occur on Oct. 23rd, with most favoring the early hours of the day. Decay time uncertainties exceed 8 hours, so it is still impossible to say exactly where ROSAT will disintegrate.

Sky watchers say ROSAT is bright and easy to see, but photographers are having a hard time catching it. Dewey Vanderhoff tracked it over Cody, Wyoming, on Oct. 18th: "It was easily the fastest-moving satellite I have ever seen, being in such a low orbit and accelerating towards its doom. I barely got off a 'shotgun' 2-second exposure as ROSAT raced between Pegasus and Pisces (image)."

On Oct. 16th, astrophotographer Thierry Legault trained his 14-inch telescope on the observatory, and this is what he saw:

A video of the flyby may be found on Legault's web site. "The satellite looks very steady," he says, "there was no sign of tumbling or flares. Visually, ROSAT was crossing the sky so fast! I hope that it will give a nice fireworks over my place when it re-enters."

Until then, sky watchers should be alert for a fast-moving light in the night sky. To catch ROSAT, check Spaceweather's Satellite Tracker for local flyby times. You can also turn your smartphone into a field-tested ROSAT tracker.

UPDATE--ROSAT FLARES! Last night, multiple observers in California reported seeing a bright flash of light from ROSAT. "In addition to the satellite screaming thru the sky because of it's low altitude, it also displayed a short brilliant flare," says Derek Breit of Morgan Hill, CA. He caught the event in this 14 MB video:


Video credit: BREIT IDEAS Obs. Morgan Hill

"I must have seen the same flare Derek captured on the 0226Z ROSAT pass over Northern California," adds Kent Yeglin. "ROSAT was 3.2 seconds earlier than expected. The magnitude was around 0 with a short-duration flare to perhaps magnitude -6 to -8, comparable to brightest Iridiums. Flare peak was very short duration -- under a second -- more of a flash."


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 October 20, 2011 there were 1256 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2011 UB
Oct 17
5 LD
--
13 m
2009 TM8
Oct 17
0.9 LD
--
8 m
2011 UL10
Oct 21
3.5 LD
--
41 m
2011 UH10
Oct 24
9.6 LD
--
17 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
2000 YA
Dec 26
2.9 LD
--
80 m
2011 SL102
Dec 28
75.9 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
Science Central
 
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  for out-of-this-world printing and graphics
Trade Show Displays
   
  more links...
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