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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 337.2 km/sec
density: 0.2 protons/cm3
explanation | more data
Updated: Today at 2230 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Dec09
24-hr: A0
0415 UT Dec09
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 09 Dec 08
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 08 Dec. 2008
Far side of the Sun:
This holographic image reveals a possible sunspot group on the far side of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 0
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 3.5 nT
Bz: 0.4 nT north
explanation | more data
Updated: Today at 2231 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole could reach Earth on Dec. 11th or 12th. However, because of the high northern latitude of the hole, the stream could miss Earth, sailing over the north pole of our planet. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2008 Dec 09 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 09 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 9, 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 120/hr to only 30/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]

CME BUBBLE: Yesterday, Dec. 8th, something exploded on the far side of the sun. The blast propelled a huge bubble of magnetized plasma over the sun's western limb where the Solar and Heliospheric Observatory (SOHO) photographed it expanding into space:

Click to play the movie

The bubble (a coronal mass ejection or "CME") is heading in the general direction of Saturn and will not hit Earth. Nevertheless, it does merit our attention. After a long spell of eerie quiet, the sun is showing signs of life, raising expectations that solar minimum is coming to an end. The months ahead will likely bring more CMEs, and not all of them will miss. Stay tuned for space weather.

SATURN'S RINGS: If you haven't looked at Saturn lately, you should. The planet's rings are vanishing. At least, that's how it seems. Saturn's rings are now almost edge-on to Earth forming a razor-thin line across the gas giant.

With the rings out of the way, Hong Kong astrophotographer "Wah!" was able to observe on Dec. 6th a transit of Saturn's moon Titan:

"This event should be quite rare, because we can see it only when Saturn's rings become very thin," he says.

He's right, it is rare, but rare is able to become commonplace. Saturn's rings are going to be this thin (and even thinner) for many months to come. Earth is experiencing a ring plane crossing. As Saturn goes around the sun, it periodically (once every 14-to-15 years) turns its rings edge-on to Earth. Because the rings are so thin, they can actually disappear when viewed through a small telescope. The moment of disappearance for this crossing is about 10 months away: Sept. 4, 2009. Thin is in!

Saturn is easy to see. Before dawn, point your backyard telescope at the bright yellow "star" in Leo: sky map.

more images: from Neil Phillips of Crayford, Kent, UK; from Dan Petersen of Racine, Wisconsin; from Masa Nakamura of Otawara, Tochigi, Japan; from Pete Lawrence of Selsey, West Sussex, UK; from David M. Frost of League City, Texas;

UPDATED: 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 9, 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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