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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 360.2 km/sec
density: 3.2 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Sep13
24-hr: A0
2340 UT Sep13
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 13 Sept. 09
The sun is blank--no sunspots.. Photo credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 12 Sept 2009

Spotless Days
Current Stretch: 11 days
2009 total: 204 days (80%)
Since 2004: 715 days
Typical Solar Min: 485 days
explanation | more info
Updated 12 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= 2 quiet
24-hr max: Kp= 3
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 6.4 nT
Bz: 0.1 nT south
explanation | more data
Updated: Today at 2347 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on Sept. 13th or 14th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Sep 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 Sep 13 2201 UTC
0-24 hr
24-48 hr
10 %
10 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
15 %
01 %
05 %
01 %
01 %
What's up in Space
September 13, 2009

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


SOLAR PROMINENCE: No sunspots, no problem. The sun can still put on a good show. Astronomers are reporting a large prominence dancing along the sun's northwestern limb. If you have a solar telescope, take a look.

sun shots: from Greg Piepol of Rockville, Maryland; from Erika Rix of Zanesville, Ohio; from Cai-Uso Wohler of Bispingen, Germany; from Michael Borman of Evansville, Indiana;

JAPANESE SHIP FLARES, CHASES ISS: Japan's new cargo ship, the HTV-1, is in Earth orbit and chasing the ISS for a rendevous on Sept. 17th. Sky watchers who have seen the vehicle say it is bright, orange, and best of all, sometimes it flares. Marco Langbroek sends this photo from Leiden, the Netherlands:

Photo details: Canon EOS 450D + EF 50/2.5 Macro, 10 seconds

"I photographed the HTV-1 on its maiden flight to the ISS on the evening of Sept. 12th; it was as bright as a 1st magnitude star," says Langbroek. "The picture also shows the trail of an old Russian rocket stage."

"Just before I took the picture, the HTV-1 briefly flared to mag. -1," he adds. Other observers confirm this, reporting flares as bright as mag. -3 or -4. The ship has few flat surfaces to reflect sunlight, so it is unclear what is causing the surges in luminosity. Pictures of the HTV-1 may be found in this JAXA press kit.

Readers, check the Simple Satellite Tracker to see if you are favored with a flyby of HTV-1. The mystery-flares are worth a look.

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 13, 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...
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