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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 372.0 km/sec
density: 6.9 protons/cm3
explanation | more data
Updated: Today at 2245 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Jul21
24-hr: A0
2245 UT Jul21
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 21 Jul 08
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 21 July 2008
Far side of the Sun:
This holographic image reveals no large sunspots on the far side of the sun. Yesterday's tentative detection of a far side spot is not confirmed. 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
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 5.2 nT
Bz: 0.6 nT north
explanation | more data
Updated: Today at 2246 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on July 22nd or 23rd. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2008 Jul 21 2204 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 21 2204 UTC
0-24 hr
24-48 hr
20 %
30 %
05 %
15 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
25 %
50 %
10 %
20 %
01 %
05 %
What's up in Space
July 21, 2008
AURORA ALERTS: Did you miss the Northern Lights of July 12th? Next time get a wake-up call from Space Weather PHONE.  

SPACE STATION FLYBYS: Sky watchers in Europe and North America are in for a treat. For the next few days, the International Space Station will be orbiting over the two continents, appearing brightly in the morning and evening sky. Check the Simple Satellite Tracker to find out when to look.

images: from Doug Zubenel of De Soto, Kansas

SHREDDED STORM: (Updated) On July 1st, a Mars-sized storm on Jupiter called the "Little Red Spot" (LRS) ran into two of its siblings: the Great Red Spot and Oval BA. Caught between the two larger storms, the Little Red Spot was torn apart. These "before and after" shots come from the Hubble Space Telescope:

One can only imagine the turmoil and shredding action that took place on July 1st when the Little Red Spot tried to squeeze itself between the other two storms, because Hubble wasn't looking when it happened; the great telescope was scheduled to observe something else that day. Nevertheless, Hubble's image of the aftermath reveals something very interesting. John Rogers, director of the Jupiter Section of the British Astronomical Association, explains:

"The July 8th Hubble image is very beautiful and informative, clearly showing the re-emerging LRS (gray arrow) at the east end of the GRS," says Rogers. "A bright ribbon from it forms a 360-deg spiral into the GRS, and I believe this is the complete remnant of the LRS, as shown in a montage I made with images from Miyazaki and other amateurs. It is amazing that the Little Red Spot has remained continuous while being stretched into a loop all the way round the GRS!"

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 21, 2008 , there were 962 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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