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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 332.8 km/sec
density: 3.5 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: A0
2340 UT May20
24-hr: A0
2340 UT May20
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 20 May 09
Sunspot group 1017 is fading rapidly and probably will be gone by the end of the day. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 20 May 2009

Spotless Days
Current Stretch: 0 days
2009 total: 115 days (83%)
Since 2004: 626 days
Typical Solar Min: 485 days
explanation | more info
Updated 20 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
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 5.7 nT
Bz: 4.2 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
NOAA Forecasts
Updated at: 2009 May 20 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 20 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 20, 2009

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


CELESTIAL TRIANGLE: Set your alarm for dawn. On Thursday morning, May 21st, Venus, Mars and the crescent Moon will form a lovely triangle in the eastern sky. It's a nice way to begin the day. Sky maps: May 20, May 21.

SPACESHIPS IN THE SUN, AGAIN: How often do you see spaceships flying in front of the sun? Astrophotographer Thierry Legault has seen it happen three times in the past week. Here he is standing on the grounds of the Kennedy Space Center with his solar-filtered telescope trained on the action:

The view through the eyepiece looked like this. It shows space shuttle Atlantis with the Hubble Space Telescope in the cargo bay on May 18th during the fifth and final spacewalk of the STS-125 Hubble repair mission.

"One hour after I took the picture, rain began to fall and it hasn't stopped for 30 hours," says Legault. "Note the shuttle sitting on pad 39B over my left shoulder. That is Endeavour, ready to fly to the rescue in the unlikely case that Atlantis could not come back."

Legault also photographed a solar transit of Atlantis on May 12th and a transit of Hubble and Atlantis in tandem on May 13th. That makes three times. You never know what you might see when you look at the sun.

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 20, 2009 there were 1056 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...
©2008, -- This site is penned daily by Dr. Tony Phillips.
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