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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 483.5 km/sec
density: 0.7 protons/cm3
explanation | more data
Updated: Today at 2245 UT
X-ray Solar Flares
6-hr max: A0
1720 UT Apr25
24-hr: A0
0900 UT Apr25
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 25 Apr 08
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 25 Apr 2008
Far side of the Sun:
This holographic image reveals no sunspots on the farside of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 3
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 3.4 nT
Bz: 1.7 nT south
explanation | more data
Updated: Today at 2246 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on April 26th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2008 Apr 25 2203 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: 2008 Apr 25 2203 UTC
0-24 hr
24-48 hr
10 %
10 %
05 %
05 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
20 %
10 %
05 %
05 %
01 %
01 %
What's up in Space
April 25, 2008
FLYBY ALERT! Would you like a phone call when the International Space Station (ISS) is about to fly over your back yard? Sign up for Space Weather PHONE.  

SATURN AND REGULUS: When the sun sets tonight, go outside and look south. You'll find a pair of starry eyes staring back at you. On the left is Saturn, on the right Regulus. The ringed planet and the first-magnitude star are only 2o apart--a very pretty pair. sky map.

AURORA AUSTRALIS: A solar wind stream is buffeting Earth's magnetic field, causing not only Northern but also Southern Lights. NSF research engineer Dana Hrubes sends this picture directly from the South Pole in Antarctica:

"This is aurora australis backlighting the 10-meter South Pole Telescope, which is bathed in moonlight at the geographic south pole where the sun has set for 6 months," says Hrubes.

Affectionately known as "SPoT," the telescope is dedicated to the study of cosmic microwave background radiation--the afterglow of the Big Bang itself. Researchers use SPoT to probe the origins of the Universe and gather data on mysterious dark energy. Because it is a radio telescope, SPoT is not adversely affected by the dancing lights overhead. Only the research engineers are distracted.

Sky watchers around both poles should be alert for more lights tonight as the solar wind continues to blow.

April 2008 Aurora Gallery
[Aurora Alerts] [Night-sky Cameras]

END OF THE RAINBOW: At long last, Lorne Thompson of Las Vegas, Nevada, has found out what lies at the end of the rainbow. It's an outhouse:

You were expecting a pot of gold?

Actually, there is no end to a rainbow. If the ground were removed, you would see that the rainbow makes a complete circle; this is called the "rainbow cone." Usually, less than half of the circle is visible because ground, hills and little blue buildings get in the way. To see more than half, go to the lofty perch of a mountaintop or an airplane. Voila!--no outhouse.

more images: from Steve Wainwright of South Wales UK; from Aslaug Ally of Ski, Norway; from Gary Shunk of Boulder, Colorado

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. [comment]
On April 25, 2008 there were 946 potentially hazardous asteroids.
April 2008 Earth-asteroid encounters:
Miss Distance
2008 FH5
Apr. 2
7.6 LD
17 m
2001 QO142
Apr. 6
34 LD
685 m
2008 GF1
Apr. 7
0.8 LD
10 m
2005 BE2
Apr. 10
62 LD
1.0 km
2005 NB7
Apr. 17
16 LD
705 m
2008 FU6
Apr. 22
62 LD
1.4 km
2005 TB
Apr. 28
47 LD
1.3 km
2001 DQ8
Apr. 30
74 LD
1.1 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 Links
NOAA Space Weather Prediction Center
  The official U.S. government bureau for real-time monitoring of solar and geophysical events, research in solar-terrestrial physics, and forecasting solar and geophysical disturbances.
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.
Daily Sunspot Summaries
  From the NOAA Space Environment Center
Current Solar Images
  from the National Solar Data Analysis Center
  more links...
©2008, -- This site is penned daily by Dr. Tony Phillips.
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