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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 371.2 km/sec
density: 3.2 protons/cm3
explanation | more data
Updated: Today at 2245 UT
X-ray Solar Flares
6-hr max: A0
2235 UT Jul31
24-hr: A0
2235 UT Jul31
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 31 Jul 08
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 31 July 2008
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: 4.8 nT
Bz: 0.9 nT south
explanation | more data
Updated: Today at 2246 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: 2008 Jul 31 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 Jul 31 2203 UTC
0-24 hr
24-48 hr
10 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
10 %
01 %
01 %
01 %
01 %
What's up in Space
July 31, 2008
AURORA ALERTS: Did you miss the Northern Lights of July 12th? Next time get a wake-up call from Space Weather PHONE.  

FLYING SPACE JUNK: The Early Ammonia Servicer (EAS), a refrigerator-sized piece of space junk thrown overboard from the International Space Station last year, is expected to re-enter Earth's atmosphere in late 2008 or early 2009. It should make a nice fireball. Meanwhile, you can see the EAS intact as it zips across the night sky almost as bright as the stars of the Big Dipper. Check the Simple Satellite Tracker for flyby times.

GET READY FOR THE SOLAR ECLIPSE: Consider it an overture. This morning in Iran, Mohamad Soltanolkottabi photographed the Moon tantilizingly close to the rising sun. "I went to Naghsh-e Jahan Square and took this picture in front of the Sheykh Lutfullah Mosque," he says.

Less than 24 hours from now, the sun and Moon will meet, converging to produce a solar eclipse. The narrow path of totality stretches from arctic Canada, across Greenland and Siberia, to millions of waiting eyes in populous China. NASA TV will broadcast the event beginning Friday, August 1st, at 6 am EDT. Don't miss it!

OVER THE HORIZON: NASA's STEREO-B spacecraft has beamed back a movie of a spectacular eruption on the sun's eastern limb. Click on the image to launch a 6 MB mpeg:

The movie spans a two day period, July 12-14, and shows a blob of gas five times the size of Earth being hurled away from the sun. Earth was not in the "line of fire" so no geomagnetic storms or auroras resulted from the blast.

Astronomers on Earth witnessed only the upper regions of the explosion. From our point of view, the action took place over the sun's horizon. STEREO-B, however, has a different point of view. STEREO-B shares Earth's orbit around the sun (approximately), but lags behind Earth by about 30 degrees. This allows the spacecraft to see "around the bend," revealing solar activity hidden from terrestrial eyes.

Seeing the hidden side of the sun is just one of many benefits of the ongoing STEREO mission; learn more from

2008 Noctilucent Cloud Gallery
[Strange Clouds] [Sky Cameras]

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 July 31, 2008 , there were 965 potentially hazardous asteroids.
July 2008 Earth-asteroid encounters:
Miss Distance
2003 YE45
July 13
16.5 LD
1.4 km
2008 BT18
July 14
5.9 LD
1.0 km
2003 LC5
July 15
62 LD
1.4 km
2008 NP3
July 17
6.8 LD
85 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 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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