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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
SPACE WEATHER
Current conditions
Solar wind
speed: 326.4 km/sec
density: 2.4 protons/cm3
explanation | more data
Updated: Today at 2247 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Dec19
24-hr: A0
0135 UT Dec19
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 19 Dec 08
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 18 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
quiet
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 3.6 nT
Bz: 2.8 nT south
explanation | more data
Updated: Today at 2118 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on Dec. 21st or 22nd. Credit: SOHO Extreme UV Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2008 Dec 19 2201 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
01 %
01 %
CLASS X
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 19 2201 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
10 %
10 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
10 %
10 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
What's up in Space
December 19, 2008

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.

 

RADIO METEORS: The Ursid meteor shower caused by Comet 8P/Tuttle peaks this year on Dec. 22nd. About a dozen meteors per hour will fly out of the Little Dipper (Ursa Minor) as Earth passes through the comet's debris stream. Watching these northern meteors can be a chilling experience, so why not stay inside and listen to them instead? Spaceweather.com is broadcasting live audio from the Air Force Space Surveillance Radar in Texas. When a meteor passes over the radar--"ping"--there is an echo. Give it a try; feedback is welcomed.

FIND THE COMET: On Dec. 12th and 13th, NASA's STEREO spacecraft photographed a coronal mass ejection (CME) billowing over the limb of the sun. Click on the image to set the scene in motion:


Play the movie: 5 MB Quicktime or avi

Now play it again. Did you see the comet? It's just a speck among the stars and billowing debris; look for it along this flight path.

The comet's name is P/2003 K2 (Christensen). It was discovered in May 2003 by astronomer Eric Christensen and then, as sometimes happens to new comets with poorly-known orbits, it was lost again. Comet Christensen went missing for more than five years until STEREO found it again. Spacecraft (especially SOHO) have discovered many comets, but this is the first time a spacecraft has recovered one: full story.

SATURN'S RINGS: You might never see Saturn's rings this skinny again. Since 2008 began, the rings have been tilting toward Earth and now they are nearly edge-on with an opening angle of only 0.8o. A composite image submitted by Efrain Morales Rivera of Aguadilla, Puerto Rico, shows how the geometry has changed:

As Saturn goes around the sun, it periodically turns its rings edge-on to Earth—once every 14-to-15 years. That's what is happening now. Earth is approaching Saturn's "ring plane," a vantage that transforms the normally wide and bright rings into a dark line bisecting Saturn's two hemispheres.

The rings will completely disappear on Sept. 4, 2009, when Earth crosses through the ring plane. Unfortunately, no one will be able to see it because Saturn will be so close to the Sun. The next ring plane crossing in plain view of Earth won't come until the year 2038.

Until then, the skinniest you're likely to see Saturn's rings is now. Saturn is easy to find in the constellation Leo just before dawn. Point your backyard telescope and behold the edge: sky map.


Dec. 2008 Aurora 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 19, 2008 there were 1010 potentially hazardous asteroids.
Dec. 2008 Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2008 WY94
Dec. 5
3.2 LD
19
35 m
2008 WG14
Dec. 5
4.8 LD
17
49 m
2008 XK
Dec. 6
1.7 LD
17
15 m
2008 XC1
Dec. 12
4.3 LD
16
102 m
2008 XB2
Dec. 13
5.8 LD
18
47 m
2006 VB14
Dec. 14
36 LD
15
795 m
2008 EV5
Dec. 23
8.4 LD
13
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.
STEREO
  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, SpaceWeather.com -- This site is penned daily by Dr. Tony Phillips.
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