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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 340.1 km/sec
density: 0.1 protons/cm3
explanation | more data
Updated: Today at 2343 UT
X-ray Solar Flares
6-hr max: C4
1719 UT Mar21
24-hr: C4
1719 UT Mar21
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 21 Mar 11
Sunspot 1175 is quiet and poses no immediate threat for strong flares. Credit: SDO/HMI
Sunspot number: 47
What is the sunspot number?
Updated 20 Mar 2011

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

Updated 20 Mar 2011


The Radio Sun
10.7 cm flux: 92 sfu
explanation | more data
Updated 20 Mar 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: 7.1 nT
Bz: 2.8 nT south
explanation | more data
Updated: Today at 2344 UT
Coronal Holes: 21 Mar 11
A solar wind stream flowing from this minor coronal hole could reach Earth on March 23rd or 24th. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Mar 21 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
30 %
30 %
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 Mar 21 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
15 %
15 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
 
Monday, Mar. 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

AURORA SEASON: Today is the first day of northern spring. Winter ended on March 20th at 7:21 pm EDT when the sun crossed the equator heading north. This event has special significance for readers of spaceweather.com because, for reasons not fully understood, spring is aurora season. Get your geomagnetic storm alerts here.

HERE COMES TROUBLE? A big sunspot is emerging over the sun's southeastern limb, and it is crackling with activity. NASA's Solar Dynamics Observatory recorded a surge of extreme ultraviolet radiation from the sunspot's magnetic canopy on March 21st:

This appears to be the return of old sunspot 1165, last seen in early March when it formed on the sun's southwestern limb. Since then it has been transiting the far side of the sun, apparently growing in size and restlessness. The potential for trouble will become more clear in the hours ahead as the active region emerges in full. Stay tuned.

SUPER LUNAR GREEN FLASH: With the moon extra-close on March 19th, sky watchers got a rare chance to see if lunar terrain is really made of green cheese. Sure enough, many people witnessed a verdant fringe atop the rising lunar disk. John Stetson sends this example from Cape Elizabeth, Maine:

"This photo is a very close approximation of how the Moon looked at the eyepiece of my telescope," says Stetson. "The orange-colored Moon was definitely topped with green."

Case closed?

"No," says atmospheric optics expert Les Cowley, "this is not proof that the Moon is made of green cheese! These green flashes are the result of a temperature inversion, abnormally warm air lying over colder air. The Moon’s rays are bent when they pass between the air layers and their colors are separated to make the mock-mirage flash."

Browse the links for more lunar green: from Malcolm Park of Whitby Ontario, Canada; from Gary A. Becker of Bethlehem, PA


March 2011 Aurora Photo Gallery
[previous Marches: 2010, 2009, 2008, 2007, 2006, 2005, 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 March 21, 2011 there were 1204 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2011 EB74
Mar 16
0.9 LD
--
18 m
2011 BE38
Apr 10
48 LD
--
1.0 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
2001 QP181
Jul 2
35.1 LD
--
1.1 km
2003 YS117
Jul 14
73.9 LD
--
1.0 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
Conquest Graphics
  for out-of-this-world printing and graphics
Science Central
   
  more links...
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