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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 275.9 km/sec
density: 2.9 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Aug15
24-hr: A0
2340 UT Aug15
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 15 Aug 09
The sun is blank--no sunspots. Photo credit: Howard Eskildsen, Ocala, Florida
Sunspot number: 0
What is the sunspot number?
Updated 14 Aug 2009

Spotless Days
Current Stretch: 35 days
2009 total: 177 days (78%)
Since 2004: 688 days
Typical Solar Min: 485 days
explanation | more info
Updated 14 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: 2.3 nT
Bz: 1.3 nT south
explanation | more data
Updated: Today at 2346 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on or about Aug. 18th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Aug 15 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 15 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 15, 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.


MORNING SHOW: If you wake up before sunrise this weekend, look east. The crescent Moon is approaching Venus for a Monday-morning close encounter. The International Space Station is likely to be there, too. So be alert for a gathering of bright lights in the dawn sky; it's a great way to start the day. Sky maps: Aug. 16th, 17th.

SPACE STATION SILHOUETTE: The sun is blank--no sunspots. That makes it a perfect backdrop for passing spaceships:

Amateur astronomer Levin Dieterle photographed the transit this morning, August 15th, from Hofstetten, Germany. "The ISS crossed the entire sun in only 0.64 seconds," he says. He captured the split-second event using a solar-filtered telescope and a Canon 40D digital camera.

The station's silhouette traces solar arrays, science labs, living quarters and a docked Russian supply ship. Next year, the outline will expand to include a cosmic ray telescope called the Alpha Magnetic Spectrometer. From its perch atop the station's massive backbone, or "truss," the telescope will scan the heavens for antimatter galaxies, strangelets, dark matter and other exotic phenomena only detectable from Earth orbit. Get the full story from Science@NASA.

PERSEIDS CUBED: Why was this year's Perseid meteor shower so good? Three reasons:

According to the International Meteor Organization, the shower peaked an extraordinary three times. The first peak, around 0800 UT on August 12th, was caused by Earth hitting a filament of dust shed by Perseid parent Comet Swift-Tuttle in 1610. The second peak, around 1800 UT on August 12th, was another cloud of dust from Comet Swift-Tuttle nudged toward Earth by the gravity of Saturn. The third peak, around 0600 UT on August 13th, is a mystery. Researchers are working now to "reverse-forecast" the shower and figure out the source of the third outburst. Stay tuned for spectulation.

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]

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 15, 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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