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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 394.0 km/sec
density: 0.9 protons/cm3
explanation | more data
Updated: Today at 2247 UT
X-ray Solar Flares
6-hr max: A0
1915 UT Dec13
24-hr: A0
1915 UT Dec13
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 13 Dec 08
Sunspot 1009 has rotated over the western limb, leaving the Earth-facing side of the sun blank. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 13 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= 0 quiet
24-hr max: Kp= 1
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 3.0 nT
Bz: 1.2 nT south
explanation | more data
Updated: Today at 2247 UT
Coronal Holes:
There are no large equatorial coronal holes on the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2008 Dec 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: 2008 Dec 13 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
December 13, 2008
NORTHERN LIGHTS: Did you sleep through the auroras of November? Next time get a wake-up call: Spaceweather PHONE.  

GEMINID METEOR SHOWER: The annual Geminid meteor shower peaks on Dec. 13th and Dec. 14th when Earth passes through a stream of debris from extinct comet 3200 Phaethon. Bright moonlight will reduce the number of visible meteors from the usual 100/hr to only 20/hr or so. That's still a nice show. For best results, watch the sky starting 10 pm local time on Saturday night (Dec 13th) until dawn on Sunday morning (Dec. 14th). [live updates] [photo]

SOMETHING NEW: is broadcasting a live audio stream from the Air Force Space Surveillance Radar in Texas. When a Geminid meteor passes over the facility, the radar echo sounds like this. Our experimental system can support 1000 simultaneous listeners. Give it a try; feedback welcomed.

GOODBYE PERIGEE MOON: Last night's full Moon was the biggest of the year, a "perigee moon" 14% wider and 30% brighter than lesser full Moons earlier in 2008. "We really didn't think we would notice the difference, but it did look bigger than usual!" says Raquel S. of Cocoa, Florida. "My whole family just watched in awe."

It's gone now, though. Elias Chasiotis photographed it this morning setting behind a hillside in Markopoulo, Greece:

Good-bye, perigee Moon!

In case you missed the show, another perigee full Moon is coming on Jan. 10, 2009. Just as last night's full Moon was the biggest of 2008, the Jan. 10th full Moon will be the biggest of 2009. Mark your calendar.

more images: from John Stetson of Sebago Lake, Maine; from Larry Fischer of Topeka, Kansas; from Kevin Witman of Cochranville, Pennsylvania; from Glenn Johnson of Tallahassee Florida; from Bill Bradley of West Hempstead, New York; from Anthony Ayiomamitis of Athens, Greece; from Carl Bernhardt of Riverside, California; from Paulo Neiva of Praia da Aguda, Portugal; from Bill Davis of Albuquerque, New Mexico; from Michael Prokosch of Huntsville, Texas; from Mariusz Lemiecha of Warsaw, Poland; from Oscar Martín Mesonero of Salamanca, Spain; from Doug Zubenel of De Soto, Kansas;

NEW ICE HALOES: Ice haloes are normally found high in the sky among frosty clouds. But lately researchers in Finland have been making their own halos near the ground. They do it by shining halogen lamps into the air downwind of snow-making machines:

Marko Riikonen of Rovaniemi, Finland, created these fantastic "angel wings" on November 5, 2008. It's more than just a pretty picture; the wings represent a serious attempt to discover new haloes and to understand old ones.

Atmospheric optics expert Les Cowley explains: "Early researchers had to rely on chance sightings of rare displays to unravel the mysteries of ice halos. Later on they journeyed to Polar Regions and especially the South Pole where halos are at their finest. They explained the halos well using models of geometrically perfect crystals aligned in just a few ways in the sky. But mysteries remain. For instance, rare Lowitz arcs refuse to be fully understood, while perfect crystals cannot explain new arcs like Moilanen's or the elliptical halos."

"Now researchers in Finland have new lamps and tools. Working at night they use halogen beams to light the high-quality crystals found a mile or more downwind of ski-slope snow guns. It’s almost (but not quite!) a laboratory where the crystals can be collected, examined and compared with the halos they make. Careful lamp and camera placement lets the 'sun' be raised or lowered and even halos normally invisible beneath our feet can be projected into the dark sky. In just one night a few days ago Marko Riikonen captured several new halos. Marko Mikkilä is even experimenting with a home-made 'Halogun.'"

"The new methods are starting to teach us that nature is richer than we thought. There are new halos galore, some from crystals with special shapes and others needing particular orientations. Will the new tools ‘clean up’ halo research or remove their mystery? More likely, they will reveal yet more puzzles. But at the same time greater understanding will be gained which will enhance the beauty and enchantment of the halos we all see from that 'old lamp' – the sun."

Great Conjunction Photo Gallery

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 13, 2008 there were 1010 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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