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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 304.1 km/sec
density: 0.5 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: C2
1704 UT Oct21
24-hr: M1
1300 UT Oct21
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 21 Oct 11
Sunspots 1324 and 1319 pose a continued threat for M-class solar flares. Credit: SDO/HMI
Sunspot number: 195
What is the sunspot number?
Updated 20 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 20 Oct 2011


The Radio Sun
10.7 cm flux: 159 sfu
explanation | more data
Updated 20 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: 3.2 nT
Bz: 0.1 nT north
explanation | more data
Updated: Today at 2344 UT
Coronal Holes: 21 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 21 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
65 %
65 %
CLASS X
10 %
10 %
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 21 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 %
 
Friday, Oct. 21, 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: Today Earth is entering 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. Observing tips: Wake up before dawn, get away from city lights, and look up at the glittering stars of Orion, Taurus and Gemini. That's the backdrop for the display. Also, the crescent Moon, Mars and Regulus will form a triangle in the eastern sky to admire during lulls in the shower. [full story] [meteor radar] [live counts]

LAST-CHANCE SIGHTINGS OF ROSAT: The massive ROSAT X-ray space telescope is making its final spiralling orbits around Earth. Most experts agree that re-entry will occur during the early hours of Oct. 23rd over a still-unknown region of our planet. Meanwhile, the satellite can still be seen slicing brightly through the night sky. On Oct. 20th, Dennis Mammana photographed it from Borrego Springs, California:

"Farewell ROSAT!" says Mammana. "The Röntgen Satellite moved quite fast as it made one its final visible passes over Southern California's Anza-Borrego Desert. I caught it on its way into Earth's shadow using a Nikon D700 digital camera."

Although Mammana noted that satellite was faint, others have seen it glowing more brightly than a first magnitude star. Derek Breit of Morgan Hill, California, witnessed a brilliant flare on Oct 18th, which he recorded in this 14 MB video. The increase in brightness was probably caused by sunlight glinting off one of ROSAT's flat surfaces.

Want to see ROSAT one last time? Check Spaceweather's Satellite Tracker for flyby times. You can also turn your smartphone into a field-tested ROSAT tracker.

According to the DLR (the German space agency), which operated the observatory while it was active in the 1990s, as many as 30 pieces of debris could reach Earth's surface. Of particular concern is the telescope's heat-resistant mirror assembly — 1.6 metric tons in all — which could hit the ground intact at hundreds of miles per hour. Odds favor an ocean splashdown or a land impact in sparsely inhabited wilderness.

ROSAT images: from Jim Turney of Cold Springs Valley, Nevada, USA; from James Beauchamp of Oklahoma City, OK; from Thierry Legault of Paris, France; from Dewey Vanderhoff of Cody, Wyoming , USA; from Olivier Staiger of Crans-Montana Switzerland


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 21, 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
--
39 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
--
200 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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