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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 357.0 km/sec
density: 3.3 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: A7
2000 UT Dec24
24-hr: A8
0250 UT Dec24
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 24 Dec. 09
Sunspots 1036 and 1038 are members of new Solar Cycle 24. Another new-cycle sunspot may be forming in the circled region. Image credit: SOHO/MDI
Sunspot number: 23
What is the sunspot number?
Updated 23 Dec 2009

Spotless Days
Current Stretch: 0 days
2009 total: 259 days (73%)
Since 2004: 770 days
Typical Solar Min: 485 days
explanation | more info
Updated 23 Dec 2009

The Radio Sun
10.7 cm flux: 78 sfu
explanation | more data
Updated 23 Dec 2009

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
Interplanetary Mag. Field
Btotal: 1.5 nT
Bz: 0.4 nT south
explanation | more data
Updated: Today at 2346 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: 2009 Dec 24 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 24 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 24, 2009

ASTRONOMY ALERTS: Looking for a unique and affordable gift? Give the heavens for Christmas at Spaceweather PHONE.


BIG INTERSTELLAR DISCOVERY: The solar system is passing through an interstellar cloud that physics says should not exist. In the Dec. 24th issue of Nature, a team of scientists reveal how NASA's Voyager spacecraft have solved the mystery. Get the full story from Science@NASA.

OH, CHRISTMAS TREE: A few days ago near Anchorage, Alaska, Shawn Standley went out to search for the perfect Christmas tree. A helpful column of light led him right to it:

"This spruce tree and a flock of passing waxwings was highlighted by a setting sun pillar," says Standley. "It was a beautiful sight."

Sun pillars are caused by ice in the air. Plate-shaped ice crystals flutter down from freezing clouds like leaves falling from trees. They act like thousands of little mirrors reflecting the light of the setting sun into a towering pillar--or Christmas-tree finder, as the case may be.

Look for sun pillars at dawn or dusk when the air is cold and the sun is hanging low. 'tis the season!

SOLAR POWER: The sun is in the pits of the deepest solar minimum in a century. For the past two years, sunspots have been rare and solar flares almost nonexistant. Fortunately, the warmth of the sun does not come from sunspots. While sunspot numbers have dropped to record lows, the total luminosity of the sun has barely changed at all, dropping less than about 0.1%.

Indeed, says English nature photographer Andrew Greenwood, "although the winter air here in Cheshire is frigid, the sun's warmth can still be felt, and shows its presence through the melting of snow." To illustrate the point in an artistic way, he took this picture yesterday using a Nikon D50:

"Here we see our world reflected in a tiny droplet of meltwater," he continues. "The surface curvature of the droplet was such that the sun appeared twice! It just goes to show that wondrous optical effects can be seen even on the smallest scale."

Take a closer look. Sunshine is powerful stuff, indeed.

December Northern Lights Gallery
[previous Decembers: 2008, 2007, 2006, 2005, 2001, 2000]

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 24, 2009 there were 1090 potentially hazardous asteroids.
Dec. 2009 Earth-asteroid encounters:
Miss Distance
2009 WV25
Dec. 1
2.9 LD
65 m
2009 WA52
Dec. 5
8.2 LD
23 m
2002 WP
Dec. 6
71.2 LD
950 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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