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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 249.6 km/sec
density: 0.4 protons/cm3
explanation | more data
Updated: Today at 2121 UT
X-ray Solar Flares
6-hr max: A0
2350 UT Nov30
24-hr: A0
0125 UT Nov30
explanation | more data
Updated: Today at: 2350 UT
Daily Sun: 04 Dec. 09
The Earth-facing side of the sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 03 Dec 2009

Spotless Days
Current Stretch: 11 days
2009 total: 254 days (76%)
Since 2004: 765 days
Typical Solar Min: 485 days
explanation | more info
Updated 02 Dec 2009

Far side of the Sun:
This holographic image reveals one possible sunspot 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
Interplanetary Mag. Field
Btotal: 2.0 nT
Bz: 0.4 nT south
explanation | more data
Updated: Today at 2345 UT
Coronal Holes:
A minor solar wind stream flowing from the indicated coronal hole could reach Earth today or tomorow. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Dec 04 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 Dec 04 2201 UTC
0-24 hr
24-48 hr
20 %
10 %
10 %
05 %
05 %
01 %
High latitudes
0-24 hr
24-48 hr
30 %
20 %
15 %
10 %
05 %
05 %
What's up in Space
December 4, 2009

SPACESHIP SIGHTINGS: Would you like a call when the space station is about to fly over your backyard? Sign up for Spaceweather PHONE.


GEMINID METEOR SHOWER: Mark your calendar. The Geminid meteor shower peaks on Dec. 13th and 14th when Earth passes through a stream of debris from extinct comet 3200 Phaethon. The Geminids have been intensifying in recent years, and 2009 could be the best year yet. Forecasters expect 140+ meteors per hour under the dark skies of a new Moon. [sky map]

SANDTRAPPED ON MARS: NASA engineers are working mightily to free Spirit from a sandtrap in the Columbia Hills of Mars. During one recent effort on Nov. 28th, Spirit's stuck wheel turned enough to roll forward 1.4 meters. The rover itself, however, moved less than a millimeter:

The view from Spirit's front hazard camera. Note the stuck wheel at left.

In this two-frame animation, the shifting of Spirit's shadow is caused not by locomotion, but rather by the sun moving overhead. All the turning really did was churn up more sand. Mission planners expect slow, if any, progress during similar drives in the weeks ahead. "The probability of success in escaping is uncertain," says NASA.

On the bright side, the soil Spirit is churning up turns out to be "supremely interesting," according to mission scientist Ray Arvidson of Washington University. It is rich in sulfates--"minerals formed in steam vents," he explains. "Steam is associated with hydrothermal activity – evidence of water-charged explosive volcanism. Such areas could have once supported life." If Spirit must be stuck, this is a good place to be. Stay tuned for updates on NASA's efforts to Free Spirit.

FULL MOON AT NOON: Full Moons are opposite the sun. That's why you can see a full Moon at midnight, but never at noon. It's an unbreakable rule. On Dec. 2nd, Brian Whittaker broke the rule. "I photographed the full Moon in the middle of the day!"

He took the picture from an airplane flying 34,000 feet above Greenland at a latitude just south of the Arctic Circle.

"It was lunchtime and the sun popped up in the south for its brief daily appearance," he says. "I looked due north, over the North Pole, and there was the Moon hanging over Japan--a full Moon at noon!"

"It is always a pleasure to fly through the Arctic," he adds. "You can see things from such a different point of view."

more points of view: from Rolando De Michiel of Bonnet Bay, New South Wales, Australia; from Ernie Mross of Boulder, Colorado; from P-M Hedén of Vallentuna, Sweden; from Pete Strasser of Tucson, AZ; from Doug Zubenel of Lenexa, Kansas

November Northern Lights Gallery
[previous Novembers: 2008, 2007, 2006, 2004, 2003, 2002, 2001]

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 December 4, 2009 there were 1084 potentially hazardous asteroids.
Nov. 2009 Earth-asteroid encounters:
Miss Distance
2009 UK14
Nov. 1
9.1 LD
29 m
2006 JY26
Nov. 2
6.7 LD
10 m
2000 XK44
Nov. 4
28.8 LD
1.1 km
2009 VA
Nov. 6
0.05 LD
6 m
2000 UJ1
Nov. 7
43.3 LD
1.2 km
2009 VT1
Nov. 9
1.4 LD
6 m
2000 TO64
Nov. 10
44.2 LD
1.9 km
2009 UK20
Nov. 12
6.5 LD
20 m
2009 VX
Nov. 12
2.6 LD
26 m
2009 VR
Nov. 13
6.6 LD
10 m
2009 WQ6
Nov. 16
0.9 LD
7 m
2009 WX7
Nov. 16
3.7 LD
20 m
2009 VC1
Nov. 18
6.0 LD
21 m
2009 WJ6
Nov. 20
0.5 LD
14 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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