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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 391.8 km/sec
density: 1.1 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: A0
2340 UT Oct23
24-hr: A0
0450 UT Oct23
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 23 Oct. 09
A new sunspot is forming at te indicated location. Photo credit: SOHO/MDI

more images: from Robert Arnold on the Isle of Skye, Scotland;
Sunspot number: 0
What is the sunspot number?
Updated 22 Oct 2009

Spotless Days
Current Stretch: 2 days
2009 total: 232 days (79%)
Since 2004: 743 days
Typical Solar Min: 485 days
explanation | more info
Updated 22 Oct 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= 4
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 2.7 nT
Bz: 1.2 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes:
Solar wind streams flowing from the indicated coronal holes could reach Earth on Oct. 23rd or 24th. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Oct 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 Oct 23 2201 UTC
0-24 hr
24-48 hr
15 %
10 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
20 %
15 %
05 %
05 %
01 %
01 %
What's up in Space
October 23, 2009

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


METEOR SHOWER UPDATE: The Orionid meteor shower is subsiding, but it's not done yet. International observers are still reporting as many as 25 Orionids per hour as Earth exits the debris stream of Halley's Comet. Readers, if you are up before dawn, keep an eye on the sky for last-minute Orionids. [sky map] [gallery]

GEOMAGNETIC ACTIVITY: High-latitude sky watchers should be alert for Northern Lights. A sharp gust of solar wind hit Earth on Oct. 21st, and the Arctic Circle is still ringing with geomagnetic activity. "[We had a] stunning display of active auroras last night," reports Thomas Hagen, who sends this picture from Tromsø, Norway:

"The entire sky turned green and stayed green for much of the night," adds Fredrik Broms of Kvaløya, Norway.

The solar wind gust that sparked the display is interesting because it likely originated with a spotless explosion in the Sun's southern hemisphere on Oct. 17th: movie. The blast hurled a faint coronal mass ejection (CME) toward Earth. Normally, CMEs reach Earth in only 2 or 3 days, but this one took a leisurely 4 days to cross the Sun-Earth divide. Why so long? Since solar minimum began in ~2007, solar physicists have noticed that CMEs have been moving in slow motion. They take a long time to get here, and they don't hit very hard when they arrive. Nevertheless, this one managed to spark some nice auroras. Browse the gallery for more.

October 2009 Northern Lights Gallery
[previous Octobers: 2008, 2007, 2006, 2004, 2003, 2002, 2001]

LOOK AT THE MOOOOON: "Last night while traveling through the Black Forest, we saw some cows on a hill with the crescent Moon behind," says German photographer Achim Schaller. "I laid down on the meadow with my Nikon D700 and photographed the close encounter."

Another close encounter is just around the corner. The Moon is moving away from the cows of the Black Forest and toward the king of planets. Look for Jupiter and the Mooooon side by side on Monday evening, Oct. 26th: sky map.

2009 Orionid Photo Gallery
[full story] [sky map] [previous years: 2006, 2008]

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 October 23, 2009 there were 1076 potentially hazardous asteroids.
Oct. 2009 Earth-asteroid encounters:
Miss Distance
2001 CV26
Oct. 8
9.8 LD
2.2 km
2009 TJ
Oct. 13
10.8 LD
130 m
2009 TM8
Oct. 17
0.9 LD
10 m
2009 TF8
Oct. 17
7.6 LD
20 m
2009 TH8
Oct. 19
4.5 LD
45 m
2009 UE
Oct. 19
2.5 LD
40 m
2009 UD
Oct. 20
2.0 LD
17 m
1999 AP10
Oct. 20
29.7 LD
2.7 km
2009 TO8
Oct. 21
7.4 LD
27 m
2009 UJ
Oct. 22
6.8 LD
25 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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