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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 328.6 km/sec
density: 0.7 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: C1
2136 UT Feb17
24-hr: C6
0146 UT Feb17
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 17 Feb 11
Sunspot 1158 poses a 25% threat for X-class solar flares. Credit: SDO/HMI
Sunspot number: 60
What is the sunspot number?
Updated 16 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 16 Feb 2011


The Radio Sun
10.7 cm flux: 114 sfu
explanation | more data
Updated 16 Feb 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 1
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 3.0 nT
Bz: 2.2 nT north
explanation | more data
Updated: Today at 2343 UT
Coronal Holes: 17 Feb 11
There are no large equatorial coronal holes on the Earth-side of the sun. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Feb 17 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
50 %
50 %
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 Feb 17 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
35 %
30 %
MINOR
20 %
10 %
SEVERE
05 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
35 %
35 %
MINOR
20 %
10 %
SEVERE
05 %
01 %
 
Thursday, Feb. 17, 2011
What's up in space
 

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Satellite flybys

INCOMING CME: A coronal mass ejection (CME) propelled toward Earth by the X2-flare of Feb. 15th should arrive during the late hours of Feb. 17th--that's today. A moderately strong geomagnetic storm is likely when it arrives. High-latitude sky watchers should be alert for auroras after nightfall.

NASA's researchers have made a time-lapse movie of the Feb. 17th explosion. Click on the arrow to play the movie, then scroll down for commentary:

This is a composite of data from two spacecraft: SOHO and the Solar Dynamics Observatory (SDO). SDO took the golden picture in the middle; it's an extreme ultraviolet image of the sun. A flash of UV radiation centered on sunspot 1158 marks the biggest solar flare since Dec. 2006. SOHO took the red picture on the outside; it's a coronagraph image. The CME en route to Earth now is visible as a willowy cloud flying away from the solar disk.

More images and movies of this event may be found here.

MYSTERIOUS SUN HALOES: Most sun haloes are circles. They surround the sun when sunbeams hit ice crystals in the air. The haloes this week in Finland, however, were not circular. Olli Leivo sends this picture from Lahti in southern Finland:


Photo details: Canon EOS 550D, 50mm, f11, 1/250s. More images: #1, #2, #3, #4

"Finland has had a spate of elliptical halos over the last few days produced by ice crystals precipitating out of low clouds. The ones Leivo photographed are superb," says atmospheric optics expert Les Cowley. "Elliptical halos are rare and we do not understand how they are formed. A popular theory is that hexagonal plate-shaped crystals with very blunt pyramidal ends make them. But ray tracing simulations using these crystals do not reproduce the halo’s fine detail properly. Moreover, these crystals are physically unrealistic because crystal faces follow lines of atoms in the crystal lattice – blunt pyramidal ends do not! The mystery remains."


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

  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 17, 2011 there were 1198 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2011 CD66
Feb 13
7.2 LD
--
18 m
2011 CL50
Feb 19
6.2 LD
--
12 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
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
   
  more links...
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