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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 330.9 km/sec
density: 4.3 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Aug13
24-hr: A0
0605 UT Aug13
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 07 Aug 09
The sun is blank--no sunspots. Credit: SOHO/MDI

The Solar and Heliospheric Observatory is passing through a telemetry keyhole. Daily sun images will be intermittently delayed until routine contact is established later this week.
Sunspot number: 0
What is the sunspot number?
Updated 12 Aug 2009

Spotless Days
Current Stretch: 33 days
2009 total: 175 days (78%)
Since 2004: 686 days
Typical Solar Min: 485 days
explanation | more info
Updated 12 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= 1 quiet
24-hr max: Kp= 2
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 3.5 nT
Bz: 1.9 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes:
There are no coronal holes on the Earth-facing side of the sun. Credit: Hinode X-ray Telescope
NOAA Forecasts
Updated at: 2009 Aug 13 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 13 2201 UTC
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
What's up in Space
August 13, 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.


SPACEWEATHER RADIO: The US Air Force Space Surveillance Radar is scanning the skies over North America. When a Perseid meteor passes overhead--"ping"--there is an echo. Tune into Spaceweather Radio for a live audio feed from the radar facility.

SUBSIDING PERSEIDS: The Perseid meteor shower is subsiding. According to the International Meteor Organization, the shower peaked on August 12th with 140 meteors per hour. Now Earth is exiting the debris stream of Comet Swift Tuttle and rates are dropping back to normal lows: data.

During the peak "we recorded a bright meteor or fireball over the Marshall Space Flight Center every 3 minutes--a fabulous rate," says Bill Cooke of NASA's Meteoroid Environment Office. This image is a composite of the 130 brightest:

Cooke's meteor detection system consists of two cameras separated by 100 miles--one in Alabama and one in Georgia. The wide baseline allows him to triangulate the trajectory of meteoroids with some accuracy. Here is a map of the Perseids shown above. "Last night, says Cooke, "the stars really did fall on Alabama!"

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

SPLIT SKY: "On my way to view the Perseid meteor shower on August 11th, I witnessed a spectacular sunset," reports Tyler Burg of Little Sioux, Iowa. "The sky seemed to split in half!"

The dark half was a vast shadow, Burg realized, and he looked around to find the source. "The shadow was cast by a thunderstorm floating between me and the sun," he says. "It was crackling beautifully with lightning."

"Later that night I witnessed 217 meteors in a 6 hour observing session," says Burg. "It was the greatest number of meteors I've ever seen in one night. In one outburst there were 41 meteors in 30 minutes, and once I saw 5 Perseids in only 30 seconds!"

more images: from Mike Holloway of Van Buren, Arkansas; from Tom Soetaert of Lawrence, Kansas; from Alan Dyer of Gleichen, Alberta, Canada; from Doug Zubenel of De Soto, Kansas

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

July 2009 Aurora Gallery
[previous Julys: 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 13, 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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