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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 331.9 km/sec
density: 6.2 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: C2
1704 UT Apr16
24-hr: C5
1414 UT Apr16
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 16 Apr 11
Sunspot 1190 has a beta-gamma magnetic field that harbors energy for M-class flares. Credit: SDO/HMI
Sunspot number: 124
What is the sunspot number?
Updated 15 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 15 Apr 2011

The Radio Sun
10.7 cm flux: 129 sfu
explanation | more data
Updated 15 Apr 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 1
explanation | more data
Interplanetary Mag. Field
Btotal: 3.0 nT
Bz: 1 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 16 Apr 11
A solar wind stream flowing from the indicated coronal hole should reach Earth sometime between April 18th and 20th. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Apr 16 2200 UTC
0-24 hr
24-48 hr
40 %
40 %
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 16 2200 UTC
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
10 %
10 %
01 %
01 %
01 %
01 %
Saturday, Apr. 16, 2011
What's up in space

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

Satellite flybys

LIVE FROM THE MOON: As the Moon waxes full this weekend, is broadcasting live views of lunar terrain from telescopes in Europe and North America. Tune in for a lunar tour, or become a broadcaster yourself.

SUNSPOT SUNSET: The face of the sun is dotted with active regions. Andrew Chan of Manila, the Philippines, 'spotted' three of them at sunset on April 15th:

Circled above, from top to bottom, are sunspots 1193, 1191 and 1190. All three showed up clearly when the low sun was dimmed by thick hazy air.

"I was driving home from work," says Chan, "and I could tell that a perfect sunset was imminent. I drove fast, arriving home just in time to grab my camera and dash toward our rooftop observatory. The sun quickly waved goodbye for the day...but not before I captured this image."

Chan didn't bother fixing a filter to his camera because Earth's atmosphere had already reduced the glare. Nevertheless, solar filters are strongly recommended for sunspot photography. Even a low sun can damage your eyes when viewed through optics. Safe and affordable sunspot observing systems are available from the Space Weather Store.

more sunsets: from Adrian Scott of Sutton, London, UK; from Bruno Nolf of Ieper- Astrolab Iris, Belgium

M-FLARE: The magnetic canopy of sunspot 1190 erupted on April 15th, producing an M-class solar flare (SDO movie). The brief blast did not, however, hurl a cloud of plasma toward Earth. NOAA forecasters estimate a 55% chance of more M-flares during the next 24 hours.

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."

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 16, 2011 there were 1218 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
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
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
2011 GA55
Jul 6
63.9 LD
1.0 km
2011 EZ78
Jul 10
37.3 LD
1.5 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.
  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
  the underlying science of space weather
Conquest Graphics
  for out-of-this-world printing and graphics
Science Central
  more links...
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