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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 351.9 km/sec
density: 3.5 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: M1
1712 UT Apr15
24-hr: M1
1712 UT Apr15
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 15 Apr 11
Sunspot 1190 has a beta-gamma magnetic field that harbors energy for Earth-directed M-class flares. Credit: SDO/HMI
Sunspot number: 131
What is the sunspot number?
Updated 14 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 14 Apr 2011


The Radio Sun
10.7 cm flux: 119 sfu
explanation | more data
Updated 14 Apr 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: 4.2 nT
Bz: 0.4 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 15 Apr 11
A solar wind stream flowing from the indicated coronal hole should reach Earth sometime between April 18th and 20th. Credit: SDO/AIA.
SPACE WEATHER
NOAA Forecasts
Updated at: 2011 Apr 15 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
55 %
55 %
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 Apr 15 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
10 %
10 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
 
Friday, Apr. 15, 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

SPINNING ASTEROID FLYBY: Newly-discovered asteroid 2011 GP59 is flying past Earth today, April 15th, not far beyond the orbit of the Moon (1.4 LD). There's no danger of a collision, but the 50-meter space rock is remarkable: It is elongated and spinning once every 7.5 minutes. This causes the asteroid to flash like a strobe light. A video taken by Joe Pollock of Appalachian State University on April 11th shows the effect nicely. Experienced amateur astronomers using mid-sized telescopes can watch 2011 GP59 strobe through the constellations Virgo and Hydra tonight with a peak brightness near 13th magnitude. [3D orbit] [ephemeris] [JPL press release] [more images: #1, #2]

STRING OF PEARLS: No, it's not a fleet of alien spacecraft. Nor is it a disintegrating comet, although the resemblence to Shoemaker-Levy 9 is striking. What could it be? Play the video, make your best guess, then scroll down for the answer.

What you just saw was sunlight glinting off a line of ten geosynchronous satellites stretched over Rigikulm, Switzerland, on March 5th. One by one, the illuminated satellites flare and then subside as they enter the shadow of our planet.

"The 'string of pearls' phenomenon is best seen during early-spring nights when the declination of the sun is equal to that of the geosychronous orbit, e.g. -7o as measured from Switzerland," says photographer Roland Stalder. "This short video sequence (130 images at 25 fps) is part of an all-night timelapse with 1630 images, where over 50 geosynchronous satellite flares can be found. A FullHD BlueRay disk can be ordered though me."

SOLAR ACTIVITY HEATS UP: No, it's not your imagination. Solar activity really is picking up, bringing an end to a century-class solar minimum. Get the full story from Science@NASA.

APRIL AURORAS: The auroras this month have been something to shout about. Just ask this happy sky watcher, photographed by Ruslan Akhmetsafin in Siberia on April 13th:

The display came at the tail end of a geomagnetic storm sparked by solar wind hitting Earth's magnetic field on April 12th. The event was so strong, it sent Northern Lights spilling over the Canadian border into US states such as Michigan and Minnesota. It could happen again on April 18-20 when another solar wind stream is expected to reach our planet. Prepare to shout! Aurora alerts: voice, text.

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 15, 2011 there were 1218 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2011 GE
Apr 13
4.8 LD
--
28 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
2011 GP59
Apr 15
1.4 LD
--
58 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
2011 GP59
Apr 15
1.4 LD
--
58 m
2009 UK20
May 2
8.6 LD
--
23 m
2002 DB4
Apr 15
62.5 LD
--
2.2 km
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
2011 GJ3
Apr 27
7.7 LD
--
24 m
2008 UC202
Apr 27
8.9 LD
--
10 m
2004 LO2
Jun 15
9.9 LD
--
48 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
2001 QP181
Jul 2
35.1 LD
--
1.0 km
2011 GA55
Jul 6
63.9 LD
--
1.0 km
2002 JC
Jun 1
57.5 LD
--
1.6 km
2011 EZ78
Jul 10
37.4 LD
--
1.6 km
2009 BD
Jun 2
0.9 LD
--
9 m
2003 YS117
Jul 14
73.9 LD
--
1.0 km
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
2011 GA55
Jul 6
63.9 LD
--
1.0 km
2011 EZ78
Jul 10
37.4 LD
--
1.6 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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