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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 407.5 km/sec
density: 0.0 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: B4
1702 UT Apr09
24-hr: C1
1545 UT Apr09
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 09 Apr 11
The Earthside of the sun is peppered with spots, but none poses a threat for strong solar flares. Credit: SDO/HMI
Sunspot number: 97
What is the sunspot number?
Updated 08 Apr 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 08 Apr 2011


The Radio Sun
10.7 cm flux: 109 sfu
explanation | more data
Updated 08 Apr 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= 3
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 4.1 nT
Bz: 0.0 nT
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 09 Apr 11
A solar wind stream flowing from the indicated coronal hole could brush against Earth's magnetic field on April 10th or 11th. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Apr 09 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
05 %
05 %
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 Apr 09 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
35 %
35 %
MINOR
10 %
05 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
40 %
40 %
MINOR
20 %
10 %
SEVERE
05 %
05 %
 
Saturday, Apr. 9, 2011
What's up in space
 

Turn your cell phone into a field-tested satellite tracker. Works for Android and iPhone.

 
Satellite flybys

AURORA WATCH: High latitude sky watchers should be alert for auroras. NOAA forecasters estimate a 40% chance of geomagnetic activity during the next 48 hours, when a solar wind stream is expected to buffet Earth's magnetic field. A coronal mass ejection (movie) detected by NASA's STEREO probes on April 9th could also reach Earth and contribute to the display on April 11th. [aurora gallery]

GRAND FILAMENT: A magnificent filament of magnetism is curling around the sun's southeastern quadrant today. Measuring more than 700,000 km from end to end, the vast structure is about twice as long as the separation between Earth and the Moon. Arrows trace the filament's meandering path in this extreme UV image from NASA's Solar Dynamics Observatory:

It's not easy for such a filament to remain suspended indefinitely above the stellar surface, and indeed a collapse is possible. Filaments falling onto the sun can trigger explosions called "Hyder flares." Is one in the offing? Readers with solar telescopes are encouraged to monitor developments.

SUN HALO: Today in upstate New York, amateur astronomer Mike Taormina aimed his solar telescope at the Grand Filament--but he saw something else instead. "A thin layer of clouds created a beautiful circular halo around the sun." He stepped back from the eyepiece and took this picture:

Sun haloes are caused by ice crystals in high clouds. With its abundance of wispy cirrus, northern spring is a good time to see the phenomenon. Keep an eye out for luminous circles and other forms around the sun.

more images: from Rana Khan of Salt lake, Kolkata, India; from Sandra Kelly of Shoreline, Washington


UPDATED: April 2011 Aurora Gallery
[previous Aprils: 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 April 9, 2011 there were 1214 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2011 GW9
Apr 6
0.5 LD
--
10 m
2011 GP28
Apr 6
0.2 LD
--
6 m
2011 FT29
Apr 7
6.3 LD
--
38 m
2011 GZ2
Apr 8
2.7 LD
--
26 m
2011 FT53
Apr 9
6 LD
--
34 m
2011 GE
Apr 13
4.8 LD
--
28 m
2002 DB4
Apr 15
62.5 LD
--
2.2 km
2011 GJ3
Apr 27
7.7 LD
--
24 m
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
--
1.0 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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