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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 429.0 km/sec
density: 4.7 protons/cm3
explanation | more data
Updated: Today at 2246 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Aug16
24-hr: A1
0850 UT Aug16
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 16 Aug 07
Sunspot 966 has faded away, leaving the sun devoid of spots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 14 Aug 2007
Far side of the Sun:
This holographic image reveals one possible sunspot 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 16 2140 UT
Interplanetary Mag. Field
Btotal: 3.7 nT
Bz: 0.6 nT south
explanation | more data
Updated: Today at 2247 UT
Coronal Holes:
Earth is entering a solar wind stream flowing from the indicated coronal hole. Credit: SOHO Extreme Ultraviolet Telescope
NOAA Forecasts
Updated at: 2007 Aug 16 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 16 2203 UTC
0-24 hr
24-48 hr
20 %
15 %
05 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
25 %
20 %
05 %
05 %
01 %
01 %
What's up in Space
August 16, 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.

BIG SURPRISE: Astronomers have discovered something they've never seen before: a star with a tail like a comet. Even more amazing is the fact that the newfound tail is attached to one of the most popular stars in the sky, a red giant named Mira. Astronomers have been watching Mira for 400 years and only recently has a NASA space telescope spotted its massive tail: full story.

SPACESHIP SIGHTING: The International Space Station (ISS) is under construction, and with each new addition the sprawling complex becomes easier to see from the ground. Last night, Mario Weigand took this picture from his balcony in Offenbach, Germany:

"I used my 11-inch Celestron telescope, and I tracked the ISS manually as it moved across the sky," he says. "Space Shuttle Endeavour is also visible in the photo."

How big is the ISS? The solar arrays (lower left) span 256 feet from tip to tip, almost as wide as a football field. The entire complex fills the eyepiece of a backyard telescope about the same as Jupiter or the rings of Saturn. Sky watchers, be alert for flybys!

more images and video: from Ralf Vandebergh of the Netherlands; from Hanno Falk of Flensburg, Germany (cross your eyes!)

NOCTILUCENT WAVES: On August 10th, scientists from SRI International at NSF's research facility in Sondrestrom, Greenland, shot a laser into a bank of noctilucent clouds (NLCs) passing overhead. "This is the best way to probe these mysterious clouds from the ground," says lidar team member Jeff Thayer of the University of Colorado. Their experiment revealed not only the clouds' height and thickness (80+ km high and ~1 km thick), but also some strange undulating waves:

"We believe the waves are caused by atmospheric gravity waves, or buoyancy waves, generated in the lower atmosphere and propagating vertically to the edge of space where noctilucent clouds are located," explains Thayer. When the waves reach the upper limit of Earth's atmosphere, "they can become unstable and crash – much like waves approaching and crashing on a beach."

"We have been 'pinging' NLCs from Greenland for more than 12 years, but every time it is exciting and novel," he says. During this particular observation, NASA's AIM satellite was flying overhead and observing the same waves from above. "The combined analysis will be extremely informative and exciting."

2007 Perseid Meteor Gallery
Updated Aug. 14, 2007

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 16, 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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