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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 298.5 km/sec
density: 2.4 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Sep11
24-hr: A0
2340 UT Sep11
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 11 Sept. 09
The sun is blank--no sunspots.. Photo credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 10 Sept 2009

Spotless Days
Current Stretch: 9 days
2009 total: 202 days (80%)
Since 2004: 713 days
Typical Solar Min: 485 days
explanation | more info
Updated 10 Sept 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= 1
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 4.9 nT
Bz: 4.2 nT north
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 Sept. 13th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Sep 11 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 Sep 11 2201 UTC
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
05 %
10 %
01 %
01 %
01 %
01 %
What's up in Space
September 11, 2009

AURORA ALERT: Did you miss the Northern Lights? Next time get a wake-up call: Spaceweather PHONE.


CALIFORNIA LANDING: Bad weather over Florida has forced NASA to target Edwards Air Force Base in California for today's landing of space shuttle Discovery. The deorbit burn is scheduled to begin at 7:47 p.m. EDT for an 8:53 p.m. landing at Edwards. [ground tracks] [updates]

SPACE STATION FLARES: One of the pleasures of watching the International Space Station (ISS) glide across the night sky is the unexpected. You never know when the ISS is going to flare. "Last night, I caught a beautiful flash of light coming from the space station," reports Tamas Ladanyi of Bend, Hungary. The flare occured just as the ISS was passing behind the battlement of a local castle:

"The parallel streak of light is space shuttle Discovery, which undocked from the ISS on Sept. 8th," says Ladanyi. Discovery did not flare, however, because the aerodynamic shuttle is too curvaceous.

Space station flares happen when sunlight glints off something flat--e.g., a solar array, a thermal radiator, an airlock door. The ISS has thousands of square feet of planar surfaces oriented at a variety of sun-angles. It's such a complicated situation, no one can predict when a glint will occur or where the reflected rays will fall on Earth.

On Sept. 10th, it was a castle in Hungary. Your back yard could be next. Check the Simple Satellite Tracker for a shot at the unexpected.

more images: from Tom King of Watauga, Texas; from Monika Landy-Gyebnar of Bánd, Hungary; from Jared Aicher of Boise, Idaho; from Blattmann of Saint-Etienne de Crossey, France; from Martin Wagner of Sonnenbuehl-Genkingen, Germany

STAR TRAILS IN MOTION: It's an astrophotographer's favorite trick: Point your camera at the stars, open the shutter, and let the world turn. The rotation of the planet beneath your feet causes the stars overhead to curve in graceful arcs known as star trails. Here are some examples.

Renowned astrophotographer Miguel Claro has added a new wrinkle to the old favorite. Click on the image to see star trails in motion:

"I made the movie on September 1st with my camera (Canon 400D) set up in a farm field in Vila Boim, Portugal, about 200km from Lisbon," says Claro. "It consists of sixty-eight 30-second exposures. Later I combined the individual images using Windows Movie Maker."

Each frame in the movie is the sum of all the previous frames. Because of this, "as we advance in the film, the signal-to-noise ratio increases. It's an interesting visual sensation." Watch for it as you play the movie again.

Star trails in motion: It's the astrophotographer's new favorite trick.

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

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 September 11, 2009 there were 1069 potentially hazardous asteroids.
Sept. 2009 Earth-asteroid encounters:
Miss Distance
2009 QC35
Sept. 2
2.9 LD
35 m
2009 HD21
Sept. 29
22.9 LD
1.0 km
1998 FW4
Sept. 29
8.6 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 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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