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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 302.5 km/sec
density: 0.4 protons/cm3
explanation | more data
Updated: Today at 2247 UT
X-ray Solar Flares
6-hr max: A4
1955 UT Sep23
24-hr: A7
0800 UT Sep23
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 23 Sept. 09
Sunspots 1026 and1027 are members of new Solar Cycle 24. Photo credit: SOHO/MDI
Sunspot number: 26
What is the sunspot number?
Updated 22 Sept 2009

Spotless Days
Current Stretch: 0 days
2009 total: 212 days (80%)
Since 2004: 723 days
Typical Solar Min: 485 days
explanation | more info
Updated 22 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= 0 quiet
24-hr max: Kp= 1
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 2.0 nT
Bz: -0.0 nT
explanation | more data
Updated: Today at 2346 UT
Coronal Holes:
There are no large coronal holes on the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Sep 23 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 23 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
September 23, 2009

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


SPACE STATION FLYBYS: If you see a spaceship tonight, it's not your imagination. The International Space Station is flying over many US towns and cities this week. It's brighter than any star, easy to see, the only trick is knowing when to look. Check the Simple Satellite Tracker for flybys.

SOLAR ACTIVITY: "Finally, the sun seems to be waking up," says astrophotographer Pete Lawrence. "There is a lot going on around new sunspot 1026. The spot's dark core is surrounded by active fibrils and a swirling magnetic filament that gives the region a nice 3D appearance." He took this picture using a Solarscope SF70:

"Moreover," he adds, "a second sunspot has appeared, number 1027, and it is growing rapidly."

Two big sunspots in one day? That hasn't happened in more than a year. Two is not enough to end the deepest solar minimum in a century; nevertheless, it is a welcome interruption. Readers with solar telescopes are encouraged to monitor developments.

more images: from Chin Wei Loon of As-syams Solar Observatory, University of Malaya, Malaysia; from Adrian Guzman of San Jose, California; from Guenter Kleinschuster of Feldbach, Austria; from Vahan Yeterian of Lompoc, California; from John C McConnell of Maghaberry Northern Ireland; from Francisco A. Rodriguez of Cabreja Mountain Observatory, Canary Islands; from Peter Paice of Belfast, Northern Ireland;

AUTUMN LIGHTS: Northern autumn has begun, and that means it's aurora season around the poles. "Last night, the Northern Lights returned to our arctic skies," reports Claus Vogel of Baffin Island, Canada. "After a summer dominated by the midnight sun, it was good to see the autumn lights again."

The display was sparked by a mild gust of solar wind. At this time of year, a mild gust is all it takes. During the weeks around equinoxes, the interplanetary magnetic field (IMF) near Earth tends to tilt south, an orientation that weakens our planet's magnetic defenses against the solar wind. The slightest gust can produce a lovely show.

"I'm looking forward to more dancing lights in the weeks ahead," says Vogel.

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 23, 2009 there were 1074 potentially hazardous asteroids.
Sept. 2009 Earth-asteroid encounters:
Miss Distance
2009 QC35
Sept. 2
2.9 LD
35 m
2009 RY3
Sept. 11
1.9 LD
50 m
2009 RR
Sept. 16
2.8 LD
33 m
2009 RG2
Sept. 21
9.1 LD
31 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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