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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 517.4 km/sec
density: 1.4 protons/cm3
explanation | more data
Updated: Today at 2347 UT
X-ray Solar Flares
6-hr max: A0
2345 UT Aug20
24-hr: A0
2345 UT Aug20
explanation | more data
Updated: Today at: 2345 UT
Daily Sun: 20 Aug 09
The sun is blank--no sunspots. Photo credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 19 Aug 2009

Spotless Days
Current Stretch: 40 days
2009 total: 182 days (79%)
Since 2004: 693 days
Typical Solar Min: 485 days
explanation | more info
Updated 19 Aug 2009

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= 4
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 3.8 nT
Bz: 0.5 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes:
There are no large coronal holes on the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Aug 20 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: 2009 Aug 20 2201 UTC
0-24 hr
24-48 hr
10 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
05 %
01 %
01 %
01 %
01 %
What's up in Space
August 20, 2009

AURORA ALERT: Did you miss the Northern Lights? In July they descended as far south as Nebraska. Next time get a wake-up call: Spaceweather PHONE.


BLANK SUN: The sun is entering its 41st consecutive day without sunspots. This remarkable string of blank suns shows that we are still in the pits of the deepest solar minimum in a century. If the streak continues for 11 more days, it will match the longest blank spell of the current cycle.

AURORA WATCH: Last night, Aug. 19-20, a solar wind stream hit Earth's magnetic field and sparked Northern Lights around the arctic circle. Sylvain Serre photographed the display under the crystal-clear skies of Salluit, an Inuit village in Nunavik, Canada:

Photo details: Canon EOS 30D, 10mm, 800iso, 3.5f, 15 sec.

"I was very surprised by the vivid colors of the auroras," says Serre. "It was a good show."

The solar wind is still blowing. High-latitude sky watchers should be alert for more auroras tonight.

August 2009 Aurora Gallery
[previous Augusts: 2008, 2007, 2006, 2005, 2004, 2003, 2002, 2001]

UNRULY STAR TRAILS: When a photographer points his camera at the North Celestial Pole and opens the shutter, stars are supposed to make long, graceful arcs around Polaris. They're called "star trails." On August 11th, some of the stars did not cooperate:

That's because they were shooting stars. "I took the picture during the Perseid meteor shower," says Tom Warner of Rapid City, South Dakota. "It is an all-night composite of 20-second exposures from my Nikon D700. The bright Moon is visible along with some of the brighter Perseids cutting across the star trails."

Browse the gallery for updated images of the best Perseid shower since 1993:

2009 Perseid Photo Gallery
[Science@NASA: The Perseids are Coming, Horse Flies and Meteors]

2009 Noctilucent Photo Gallery
[previous years: 2008, 2007, 2006, 2005, 2004, 2003]

Explore the Sunspot Cycle

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 20, 2009 there were 1067 potentially hazardous asteroids.
August 2009 Earth-asteroid encounters:
Miss Distance
2009 MC9
Aug. 7
70.3 LD
1.2 km
2009 OF
Aug. 8
15.4 LD
220 m
2007 RQ17
Aug. 9
8.4 LD
130 m
2000 LC16
Aug. 17
75.6 LD
2.0 km
2006 SV19
Aug. 21
59.2 LD
1.3 km
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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