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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 364.4 km/sec
density: 1.3 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: A4
2305 UT May11
24-hr: A4
2305 UT May11
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 10 May 09
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 10 May 2009

Spotless Days
Current Stretch: 10 days
2009 total: 112 days (86%)
Since 2004: 623 days
Typical Solar Min: 485 days
explanation | more info
Updated 10 May 2009

Far side of the Sun:
This holographic image reveals no sunspots on the far side of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 2
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 2.7 nT
Bz: 0.1 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes:
There are no large coronal holes on the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 May 11 2201 UTC
0-24 hr
24-48 hr
01 %
01 %
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: 2009 May 11 2201 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 %
What's up in Space
May 11, 2009

AURORA ALERT: Did you sleep through the Northern Lights? Next time get a wake-up call: Spaceweather PHONE.


DESTINATION HUBBLE: After a smooth countdown and picture-perfect liftoff, space shuttle Atlantis and a crew of seven astronauts are in space, ready to begin their 11-day mission to service NASA's Hubble Space Telescope. Atlantis lifted off Launch Pad 39A at NASA's Kennedy Space Center in Florida at 2:01 p.m. EDT. [more]

EUROPA OCCULTS GANYMEDE: On May 8th, Anthony Wesley of Murrumbateman, Australia, recorded a very rare event--one of Jupiter's moons eclipsing another. "Here," says Wesley, "is an animation of Europa passing directly in front of Ganymede."

He made the movie using a 13-inch telescope and a digital video camera. "Seeing was not good, so I was only able to use 250 of the 1200 frames I collected." Nevertheless, it is an extraordinary observation, showing the distant moons as genuine world-like disks as they pass in "mutual occultation."

Earth is moving through the orbital plane of Jupiter's satellites, allowing the moons to line up for events such as Wesley recorded on May 8th. This special geometry comes along approximately once every 6 years. The last time was in 2002-2003, and now it is happening again. Between April and December of 2009, observers around the world can see Jupiter's moons passing one in front of another as they circle the giant planet. As part of the International Year of Astronomy, professional astronomers are organizing a worldwide observing campaign to record as many of these events as possible. Click here for details.

SATELLITE COLLISION: On Feb. 10th, 2009, Iridium 33 collided with Cosmos 2251 over northern Siberia, and the two satellites were shattered. US Strategic command has since catalogued 981 pieces of debris. On this three-month anniversary of the collision, veteran satellite observer Daniel Deak has prepared a set of 3D maps showing where the fragments are located:

Maps--Iridium 33: #1, #2, #3, Cosmos 2251: #1, #2, #3

The image above pinpoints the fragments of Cosmos 2251 on May 10th. A complementary map shows the debris from Iridium 33.

A comparison of the two maps, Iridium 33 vs. Cosmos 2251, shows that the Cosmos satellite was not only broken into more pieces but also scattered more widely. "Sixteen pieces of Cosmos 2251 have already reentered Earth's atmosphere vs. only 9 pieces of Iridium 33," notes Deak.

Indeed, the Iridium satellite seems to have held together better than its Russian counterpart. One piece of Iridium wreckage is so large it may be seen with the unaided eye flashing every 4.7 seconds as it tumbles through the night sky. Check the Simple Satellite Tracker for flyby times.

April 2009 Aurora Gallery
[previous Aprils: 2008, 2007, 2006, 2005, 2004, 2003, 2002]

Explore the Sunspot Cycle

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 May 11, 2009 there were 1054 potentially hazardous asteroids.
May 2009 Earth-asteroid encounters:
Miss Distance
2009 JA
May 4
7.5 LD
37 m
2006 FG3
May 6
60.7 LD
1.1 km
2001 SG286
May 17
11.5 LD
280 m
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 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 and Heliospheric Observatory
  Realtime and archival images of the Sun from SOHO.
  3D views of the sun from NASA's Solar and Terrestrial Relations Observatory
Daily Sunspot Summaries
  from the NOAA Space Environment Center
Current Solar Images
  from the National Solar Data Analysis Center
Science Central
  more links...
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