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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 310.8 km/sec
density: 5.0 protons/cm3
explanation | more data
Updated: Today at 2246 UT
X-ray Solar Flares
6-hr max: A1
1910 UT Aug21
24-hr: A4
0250 UT Aug21
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 20 Aug 07
Not shown in this SOHO image, a new sunspot is emerging over the sun's eastern limb. PHOTOS: from Pavol Rapavy of Rimavska Sobota, Slovakia; from P-M Heden of Sweden; from Howard Eskildsen of Florida.
Sunspot number: 0
What is the sunspot number?
Updated 20 Aug 2007
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= 3
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Updated: 2007 Aug 21 2148 UT
Interplanetary Mag. Field
Btotal: 2.1 nT
Bz: 0.4 nT south
explanation | more data
Updated: Today at 2247 UT
Coronal Holes:
There are no large coronal holes on the Earth-facing side of the sun today. Credit: SOHO Extreme Ultraviolet Telescope
NOAA Forecasts
Updated at: 2007 Aug 21 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: 2007 Aug 21 2203 UTC
0-24 hr
24-48 hr
20 %
15 %
05 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
25 %
20 %
10 %
01 %
01 %
01 %
What's up in Space
August 21, 2007
Where's Saturn? Is that a UFO--or the ISS? What's the name of that star? Get the answers from mySKY--a fun new astronomy helper from Meade.

LONDON FIREBALL? Andrew J. Brown of Chelmsford in Essex (35 miles north of London) reports a bright fireball tonight at 20:41 UT. "I happened to look out of the window and saw through the thin cloud layer a bizarre 'flaming' orange object about 1/4 the diameter of the full moon. It moved slowly from north to south at about the same pace as the ISS." Confirming reports and photos are welcomed.

DOUBLE FLYBYS COME TO AN END: Space shuttle Endeavour landed today at Kennedy Space Center. This brings to an end the spectacular double flybys of Aug. 19th and 20th when Endeavour and the International Space Station (ISS) orbited in tandem over the USA and Canada. Joe Westerberg took this picture of the pair soaring over the Joshua Tree National Park in California:

The ISS will continue to make nighttime appearances for the rest of the week--alone now but still splendid in isolation: flyby alerts.

more images: from Brian Klimowski of Flagstaff, Arizona; from Jeremy Perez of Flagstaff, Arizona, USA; from Michael Reuter of Oak Ridge, TN; from Ted Jerome of West Lebanon, NH; from Bill R. of Longmont, CO; from Richard McCoy of Mead, CO; from Ron Hodges of Midland, TX; from Michael Boschat of Halifax, Nova Scotia; from Sam Ballin of Tujunga, CA; from Peter Lipscomb of Santa Fe, NM.

MARK YOUR CALENDAR: Where will you be ten years from now? Hopefully in the path of totality. On Aug. 21, 2017, there will be a total eclipse of the sun directly above the continental United States. Graphic artist Larry Koehn created this animated preview:

Click to view a full-sized map

The path of totality crosses hundreds of US towns and cities including Salem, Kansas City, St. Louis, and Nashville. Residents of those places can experience the cool sweep of the Moon's shadow and the ghostly, shimmering solar corona without even leaving their own back yard. But many people will travel--to Kentucky. A spot just northwest of Hopkinsville KY will be in the Moon's shadow longer than any other, a full 2 minutes and 40 seconds. Eclipse chasers--people who once were normal, but now race to the four corners of the Earth to catch their next eclipse--say that's enough time to change your life. Learn more from

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 August 21, 2007 there were 878 potentially hazardous asteroids.
July 2007 Earth-asteroid encounters:
Miss Distance
2007 FV42
July 2
53 LD
1.2 km
2007 MB4
July 4
7.6 LD
130 m
2007 DT103
July 29
9.3 LD
550 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 Environment 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...
©2007, -- This site is penned daily by Dr. Tony Phillips.
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