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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 445.4 km/sec
density: 1.5 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: A4
2325 UT Apr23
24-hr: A4
2325 UT Apr23
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 23 Apr. 10
Yesterday's tiny proto-sunspot dissolved before it could be numbered by NOAA. Officially, the sun remains blank for the 8th day in a row. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 22 Apr 2010

Spotless Days
Current Stretch: 8 days
2010 total: 15 days (13%)
2009 total: 260 days (71%)
Since 2004: 785 days
Typical Solar Min: 485 days
explanation | more info
Updated 21 Apr 2010

The Radio Sun
10.7 cm flux: 76 sfu
explanation | more data
Updated 22 Apr 2010

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 5
explanation | more data
Interplanetary Mag. Field
Btotal: 5.4 nT
Bz: 0.3 nT south
explanation | more data
Updated: Today at 2347 UT
Coronal Holes:
Earth is inside a solar wind stream flowing from the indicated coronal hole. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2010 Apr 23 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: 2010 Apr 23 2201 UTC
0-24 hr
24-48 hr
10 %
10 %
05 %
05 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
15 %
10 %
10 %
01 %
01 %
What's up in Space
April 23, 2010

NEW AND IMPROVED: Turn your iPhone or iPod Touch into a field-tested global satellite tracker. The Satellite Flybys app now works in all countries.


BREATHTAKING IMAGES OF THE SUN: NASA's Solar Dynamics Observatory is beaming back stunning new images of the sun, revealing our own star as never seen before. Even veteran solar physicists say they are amazed by the data. Take a deep breath, then take a look.

ASH AND AURORAS: There something in the air in Iceland--and its not all volcanic ash. Last night (April 22nd), recently-gray Icelandic skies turned green when a solar wind stream hit Earth's magnetic field:

"I hope these are not the last auroras of spring," says photographer Wioleta Zarzycka. "The midnight sun is coming to the Arctic Circle, and soon we may not be able to see the Northern Lights." Then it would be all ash.

But it hasn't come to that yet. The solar wind is still blowing and more geomagnetic activity is possible tonight. High-latitude sky watchers should remain alert for auroras.

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

SHUTTLE FLARE: On April 20th, just hours before space shuttle Discovery landed in Florida, the orbiter soared over Germany. From the darkness of his backyard observatory, Dirk Ewers watched the shuttle's last pass and was amazed when Discovery suddenly and dazzlingly flared. Here are three frames from a video he recorded through his 5-inch refracting telescope:

Click to make the shuttle flare!

There was no explosion. The flare is sunlight reflecting from shiny surfaces in the shuttle's payload bay. The bay doors were open at the time of the overpass, and the bay contained the big, glistening Leonardo Multi-Purpose Logistics Module. "At the beginning of the flare, I think Leonardo can be seen as a bright point in a partially dark open payload bay," says Ewers.

Leonardo is a cargo container. It was used this month by the crew of Discovery to ferry supplies and laboratory equipment to the International Space Station (ISS). Later this year, Leonardo will be pressurized and permanently attached to the ISS as a roomy new module. Then the ISS will have the same "flare capability" just demonstrated by the shuttle.

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 23, 2010 there were 1116 potentially hazardous asteroids.
April 2010 Earth-asteroid encounters:
Miss Distance
2010 GV23
April 5
2.1 LD
12 m
2010 GF7
April 8
2.8 LD
30 m
2010 GA6
April 9
1.1 LD
27 m
2010 GM23
April 13
3.4 LD
47 m
2005 YU55
April 19
5.9 LD
185 m
2009 UY19
April 23
8.8 LD
87 m
2002 JR100
April 29
8.0 LD
65 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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