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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
SPACE WEATHER
Current conditions
Solar wind
speed: 335.8 km/sec
density: 1.0 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: A0
2340 UT May21
24-hr: A0
1215 UT May21
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 21 May 09
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 21 May 2009

Spotless Days
Current Stretch: 1 days
2009 total: 115 days (83%)
Since 2004: 626 days
Typical Solar Min: 485 days
explanation | more info
Updated 21 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= 2 quiet
24-hr max: Kp= 2
quiet
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Interplanetary Mag. Field
Btotal: 2.7 nT
Bz: 1.1 nT north
explanation | more data
Updated: Today at 2346 UT
Coronal Holes:
There are no coronal holes on the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2009 May 21 2201 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
01 %
01 %
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: 2009 May 21 2201 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 %
What's up in Space
May 21, 2009

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

 

SEVEN SISTERS AND THE SUN: You can't see it, but the Solar and Heliospheric Observatory (SOHO) can. A conjunction is underway between the Pleiades and the sun. Using its coronagraph to block the sun's glare, SOHO is monitoring the heavenly encounter. Click here for a ringside seat.

JUST HANGIN' AROUND: Regard the pair of photos below. Now cross your eyes and you will see what it is like to work on the Hubble Space Telescope:


Click to view a larger image and alternate left-right pairs

The stereo pair, prepared by graphic artist Patrick Vantuyne of Belgium, shows spacewalker Andrew Feustal "just hangin' around" shuttle Atlantis' cargo bay on May 18th. Feustal had paused for fellow spacewalker John Grunsfeld to take his picture during a grueling 7 hour 2 minute spacewalk that put the finishing touches on NASA's masterpiece STS-125 Hubble repair mission. Thanks to their efforts, Hubble is back in orbit and working again, better than ever. Meanwhile, the crew of Atlantis is scheduled to land in Florida on Friday, May 22nd, at 10:00 am EDT, although bad weather threatens to delay their return. Stay tuned for updates.

GREEN FLASH: Green flashes from the sun are brief and elusive. You can miss one simply by blinking. So imagine the surprise of Lance B. of the Cayman islands on May 17th when he watched a flash endure for two ... long ... seconds. "I had enough time to take this picture," he says:

The green spot on the horizon is the flash showing itself during the very last seconds of sunset.

Green flashes happen when the normally mild refraction of Earth's atmosphere is amplified by a mirage. "The mirage occurs when there is warm air immediately over the ocean and the air temperature gradient changes rapidly with height," says atmospheric optics expert Les Cowley. "For the flash to be visible the warm air layers must be below you."

"The air was still and very hot; I knew the conditions were favorable," says Lance. "This was the longest green flash I've ever seen!"

more images: from Paul Edmondson of Point Reyes, CA; from Wolfgang Ott of Stuttgart, Germany; from James Helmericks of Colville River Delta, Northern Alaska;


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 21, 2009 there were 1056 potentially hazardous asteroids.
May 2009 Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2009 JA
May 4
7.5 LD
18
37 m
2006 FG3
May 6
60.7 LD
17
1.1 km
2001 SG286
May 17
11.5 LD
16
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.
STEREO
  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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