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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 450.4 km/sec
density: 2.1 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Sep15
24-hr: A0
2340 UT Sep15
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 15 Sept. 09
The sun is blank--no sunspots.. Photo credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 14 Sept 2009

Spotless Days
Current Stretch: 13 days
2009 total: 206 days (80%)
Since 2004: 717 days
Typical Solar Min: 485 days
explanation | more info
Updated 14 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= 2
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 3.5 nT
Bz: 1.4 nT south
explanation | more data
Updated: Today at 2345 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole could reach Earth as early as Sept. 17th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Sep 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 Sep 15 2201 UTC
0-24 hr
24-48 hr
20 %
15 %
05 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
25 %
20 %
05 %
01 %
01 %
01 %
What's up in Space
September 15, 2009

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


MORNING SHOW: Set your alarm for dawn. On Wednesday morning, Sept. 16th, Venus will rise in the east right beside an exquisite 7% crescent Moon. It's a beautiful way to begin the day: sky map.

SOLAR ACTIVITY: Today, the Solar and Heliospheric Observatory (SOHO) is monitoring an enormous prominence on the sun's southeastern limb. Behold three hours of fiery action:

The prominence has been growing for more than a day. As it towers higher and higher above the surface of the sun, the odds increase that it will erupt and come crashing down--a must-see. Readers, if you have a solar telescope, train your optics on the sun's southeastern limb.

more images: from J. Macieszek and J. Stetson of South Portland, Maine

AUTUMN LIGHTS: For reasons not fully understood by researchers, the weeks around equinoxes are the best times to see Northern Lights. The northern autumnal equinox of 2009 is only a week away and--voilĂ !--the show has begun:


"I had 8 people with me for an Aurora Photography Tour in Yellowknife on Sept. 12th," writes Yuichi Takasaka from the Northwest Territories of Canada. "Northern Lights started to appear from 10pm local time and stayed well after 4am!"

At this time of year, the interplanetary magnetic field near Earth tends to point south, an orientation that weakens Earth's magnetic defenses against the solar wind. Under such conditions, the slightest gust of solar wind can fuel a lovely display. Polar sky watchers should be alert for Northern Lights in the weeks ahead.

Sept. 2009 Aurora Gallery
[previous Septembers: 2008, 2007, 2006, 2005, 2004, 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 15, 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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