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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 357.7 km/sec
density: 9.1 protons/cm3
explanation | more data
Updated: Today at 2342 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Aug10
24-hr: A0
2340 UT Aug10
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 09 Aug 2009

Spotless Days
Current Stretch: 30 days
2009 total: 172 days (78%)
Since 2004: 683 days
Typical Solar Min: 485 days
explanation | more info
Updated 09 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= 2
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 0.6 nT
Bz: 0.1 nT south
explanation | more data
Updated: Today at 2343 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 10 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 10 2201 UTC
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
10 %
10 %
01 %
01 %
01 %
01 %
What's up in Space
August 10, 2009

THERE'S AN APP FOR THAT: You can now experience the Perseid meteor shower on your iPhone. It's cloud-proof! Learn more and give it a try.


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.

PERSEID FIREBALL: "On August 9th I photographed 17 Perseids," reports John Chumack of Dayton, Ohio. "The best one was a fireball of magnitude -8, about 40 times brighter than Venus. It had a double explosion, too!"

"The Perseid meteor shower is definitely underway," he says.

It should get even better in the nights ahead. Members of the International Meteor Organization are now counting more than 25 Perseids per hour: data. The rate is expected to increase almost 10-fold on the night of August 11th and 12th when Earth passes through a denser-than-usual filament of comet dust crossing Earth's orbit. Oberving tips may be found in the Science@NASA story "The Perseids are Coming."

2009 Perseid Photo Gallery
[previous Perseids: 2008, 2007, 2006, 2005, 2004, 2001]

EVOLUTION OF AN IMPACT: Since July 19th, when Anthony Wesley of Australia discovered the scattered remains of a mystery impactor in the high clouds of Jupiter, amateur astronomers around the world have been photographing the planet every night. "German astronomer Hans Joerg Mettig has converted some of the best images into polar projections," says Theo Ramakers, "and I have stitched them together to make a movie." Click on the image to set the scene in motion:

Animations: large, small, zoom

The 3-week animation, which begins with Wesley's discovery image, shows the cindery cloud expanding, swirling, and ultimately being torn into three or more pieces by turbulent south polar winds. "The spot has really progressed dramatically," says Ramakers.

No one knows how the movie will end. Planetary scientists say the debris could evolve in interesting and unexpected ways before it finally disperses some weeks from now. Astronomers who wish to contribute scenes can monitor the cloud near Jupiter's System II longitude 210°. For predicted times when it will cross the planet's central meridian, add 2 hours to Sky and Telescope's predicted transit times for Jupiter's Great Red Spot.

more images: from Mike Hood of Kathleen, Georgia; from George Tarsoudis of Alexandroupolis - Evros, Greece; from W.Verhesen of Sittard, The Netherlands; from Glenn Jolly of Gilbert, Arizona; from Alphajuno of League City, Texas;

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 10, 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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