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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 537.5 km/sec
density: 0.5 protons/cm3
explanation | more data
Updated: Today at 2247 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Dec23
24-hr: A0
2245 UT Dec23
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 23 Dec 08
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 21 Dec. 2008
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= 3 quiet
24-hr max: Kp= 3
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 4.7 nT
Bz: 2.5 nT south
explanation | more data
Updated: Today at 2247 UT
Coronal Holes:
Earth is inside a solar wind stream flowing from the indicated coronal hole. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2008 Dec 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: 2008 Dec 23 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 %
01 %
01 %
01 %
What's up in Space
December 23, 2008

UNIQUE CHRISTMAS GIFT: For less than the cost of a night at the movies, you can give someone the heavens for Christmas. Now available: gift subscriptions to Spaceweather PHONE.


SATURN'S CRAZY CHRISTMAS TILT: The planet Saturn is doing something rare and beautiful this holiday season. Find out what in today's story from Science@NASA.

COLD SHOWER: Every year on Dec. 22nd, the Ursid meteor shower puts on a mild but pleasing show. Almost no one watches, and here's why: "Last night was the coldest night of the year with wind chills near -30 F," reports John Chumack of Dayton, Ohio. "I could not stay outside more than 10 minutes at a time." Nevertheless, he did manage to photograph a few Ursids:

"I hope others who braved the cold saw some, too," he says.

Several thousand people decided to stay inside and listen. is broadcasting a live audio feed from the Air Force Space Surveillance Radar in Texas. When a meteor passes over the facility--"ping"--there is an echo. Listeners say the Ursids put on a nice radio show with as many as dozens of pings per hour.

Another cold shower is coming: the Quadrantids. Much stronger than the Ursids, the Quadrantids could produce 100+ meteors per hour when the shower peaks over western North America on the morning of Jan. 3, 2009. It's going to be cold outside and the Spaceweather meteor radar will be running. Stay tuned.

more images: from P-M Hedén of Ålbo, Sweden; from Brian Emfinger of Ozark, Arkansas; from Doug Zubenel at Pottawatomie State Fishing Lake, Kansas;

INDUSTRIAL GRADE DIAMOND DUST: "A few mornings ago, I was driving to work on Green Bay's highest bridge when a mixture of fog and emissions from local smokestacks drifted across the highway," reports Peg Zenko from Wisconsin. "Traffic slowed to a crawl. I looked up in my rearview mirror and noticed this beautiful sun pillar."

"I call the photo Industrial Grade Diamond Dust," she says.

Diamond dust is a fanciful name for low-temperature ice crystals floating close to the ground. "The air temperature over the bridge was only -9 F," notes Zenko, "and winds were mild." These conditions caused water vapor in the smog to crystallize and hover at traffic-level. The crystals caught the rays of the rising sun and voilà--a sun pillar!

Winter weather storming across Canada and the northern USA is setting the stage for some wonderfully icy displays. There are sun pillars, sundogs, 22o haloes and a variety of luminous arcs. "I suggest pulling to the side of the road," says Zenko. Diamond dust can be very distracting!

more images: from Dave Boyle of Edmonton, Alberta, Canada; from Gary Cobus near Belle Plain, Minnesota;

Dec. 2008 Northern Lights Gallery
[Previous Decembers: 2007, 2006, 2005, 2001, 2000]

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 December 23, 2008 there were 1011 potentially hazardous asteroids.
Dec. 2008 Earth-asteroid encounters:
Miss Distance
2008 WY94
Dec. 5
3.2 LD
35 m
2008 WG14
Dec. 5
4.8 LD
49 m
2008 XK
Dec. 6
1.7 LD
15 m
2008 XC1
Dec. 12
4.3 LD
102 m
2008 XB2
Dec. 13
5.8 LD
47 m
2006 VB14
Dec. 14
36 LD
795 m
2008 EV5
Dec. 23
8.4 LD
435 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
  a one-stop hub for all things scientific
  more links...
©2008, -- This site is penned daily by Dr. Tony Phillips.
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