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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 361.4 km/sec
density: 0.2 protons/cm3
explanation | more data
Updated: Today at 2249 UT
X-ray Solar Flares
6-hr max: B4
1840 UT Feb23
24-hr: C1
1223 UT Feb23
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 23 Feb 11
The chance of M-class flares from departing sunspot complex 1161-1162 has sharply dropped to only 5%. Solar activity is low. Credit: SDO/HMI
Sunspot number: 34
What is the sunspot number?
Updated 22 Feb 2011

Spotless Days
Current Stretch: 0 days
2011 total: 1 day (2%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 820 days
Typical Solar Min: 486 days

Updated 22 Feb 2011


The Radio Sun
10.7 cm flux: 91 sfu
explanation | more data
Updated 22 Feb 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: 4.1 nT
Bz: 0.6 nT north
explanation | more data
Updated: Today at 2250 UT
Coronal Holes: 23 Feb 11
A solar wind stream flowing from this shallow coronal hole could brush past Earth on Feb. 24th or 25th. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Feb 23 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
01 %
01 %
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: 2011 Feb 23 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
10 %
10 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
10 %
15 %
MINOR
01 %
05 %
SEVERE
01 %
01 %
 
Wednesday, Feb. 23, 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

SOLAR SAIL SIGHTINGS: NASA's first Earth-orbiting solar sail, NanoSail-D, is making a series of passes over North America this week. It's not very bright--that is, until it flares. Photograph one of those outbursts and you might win $500. Flyby predictions may be found on the web or on your cell phone. Good luck!

APPROACHING ACTIVE REGION: A significant active region is set to emerge over the sun's northeastern limb. The underlying sunspots are not yet visible from Earth, but the region's towering magnetic canopy is already in view. NASA's Solar Dynamics Observatory (SDO) took this picture during the early hours of Feb. 23rd:

A better view is had by NASA's STEREO-B probe, stationed over the sun's eastern limb where it can see the region from top down. Recent movies beamed back by STEREO-B show flashes of extreme UV radiation and hints of magnetic instability. This could herald a period of renewed solar activity when the region turns toward Earth in the days ahead. Or the action could peter out beforehand. Stay tuned for updates.

FIND THE ICE: Not all the ice in this picture is on the rocks. Some of it is in the air. Airborne ice crystals caused the luminous sun pillar witnessed yesterday at sunset by Bryan Hansel on the shores of Lake Superior:

"Just after the sun set, a tall pillar appeared over the lake," says Hansel. "As we watched, we could see icy clouds moving through the column of light."

In the northern hemisphere, February is a good time of year to see this phenomenon. Flat six-sided crystals flutter down from the clouds like leaves falling from trees. Aerodynamic friction tends to align their flat faces parallel to the ground. When low sunbeams hit all those icy mirrors, voila!--a sun pillar. Look for them at sunrise or sunset.


February 2011 Aurora Photo Gallery
[previous Februaries: 2010, 2009, 2008, 2007, 2006, 2004, 2003, 2002]


NanoSail-D Photo Gallery
[NASA: Solar Sail Stunner] [Photo Contest]

  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 February 23, 2011 there were 1198 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2011 CL50
Feb 19
6.2 LD
--
13 m
2003 YG118
Feb 20
67.7 LD
--
1.8 km
2000 PN9
Mar 10
45.5 LD
--
2.6 km
2002 DB4
Apr 15
62.5 LD
--
2.2 km
2008 UC202
Apr 27
8.9 LD
--
10 m
2009 UK20
May 2
8.6 LD
--
23 m
2008 FU6
May 5
75.5 LD
--
1.2 km
2003 YT1
May 5
65.3 LD
--
2.5 km
2002 JC
Jun 1
57.5 LD
--
1.6 km
2009 BD
Jun 2
0.9 LD
--
9 m
2002 JB9
Jun 11
71.5 LD
--
3.2 km
2001 VH75
Jun 12
42.2 LD
--
1.1 km
2004 LO2
Jun 15
9.9 LD
--
48 m
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
Conquest Graphics
  for out-of-this-world printing and graphics
Science Central
   
  more links...
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