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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 335.8 km/sec
density: 1.5 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: A2
2220 UT Dec28
24-hr: A3
0640 UT Dec28
explanation | more data
Updated: Today at: 2225 UT
Daily Sun: 28 Dec. 09
Sunspot 1039 is a member of new Solar Cycle 24. Image credit: SOHO/MDI
Sunspot number: 17
What is the sunspot number?
Updated 27 Dec 2009

Spotless Days
Current Stretch: 0 days
2009 total: 260 days (72%)
Since 2004: 771 days
Typical Solar Min: 485 days
explanation | more info
Updated 27 Dec 2009

The Radio Sun
10.7 cm flux: 77 sfu
explanation | more data
Updated 27 Dec 2009

Far side of the Sun:
This holographic image reveals no large 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: 3.0 nT
Bz: 0.9 nT south
explanation | more data
Updated: Today at 2345 UT
Coronal Holes:
There are no large coronal holes in the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2009 Dec 28 2201 UTC
0-24 hr
24-48 hr
05 %
05 %
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 28 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 28, 2009

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


SIGNS OF LIFE ON THE SUN: 2009 is ending with a flurry of sunspots. So far this month, the visible disk of the sun has had spots 67% of the time, a sharp increase compared to the annual average. Furthermore, all six of December's sunspot groups have been members of new Solar Cycle 24. These numbers could herald the sun's awakening from the deepest solar minimum in nearly a century and a livelier sun in 2010.

ARCTIC SUNRISESET: At this time of year, the sun never rises above the Arctic Circle. But that doesn't mean it's dark up there. Consider this photo taken yesterday from the Inuit village of Kivalina in arctic Alaska:

"Here in Kivalina (latitude 67°43' N), the sunrises and sunsets meld together as the sun stays just below the horizon during the middle of the day," explains photographer Patrick Stonehouse. "These 'sunrisesets' paint the sky and Arctic Ocean in vivid colors. The figure in the foreground is an Inuit paddling his boat out on a seal hunt."

The sunriseset will fracture on Jan. 6, 2010, when the noon sun appears in full over Kivalina and produces a distinct sunrise and sunset for the first time in more than a month. Stay tuned for photos of that.

JACK FROST: Over the weekend, Jack Frost paid a visit to Pennsylvania. "This morning when I went out to get my newspaper, I found my cars covered in a spectacular assortment of frost patterns," says Jeff Orner of Boiling Springs. "I had to hurry before the sun rose and rendered them gone forever."

The evening before there had been "a light rain and sub-freezing temperatures," says Orner. This set the stage for a great display of morning frost.

It works like this: When air is saturated with water, water molecules can crystalize on freezing surfaces, transforming directly from an amorphous vapor to a crystalline solid. This is called depositional frost or hoarfrost. Tiny manufacturing imperfections, scratches, and/or dust on car doors, windshields and hoods serve as nucleation points for the crystalization process. From such humble beginnings, spectacular frost patterns form.

Is it cold and damp where you live? Be alert for Jack Frost.

more images: from Charlie Flindt of Hinton Ampner, Hampshire, England.

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 28, 2009 there were 1091 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
2009 XO2
Dec. 23
8.6 LD
85 m
2009 YR
Dec. 25
4.3 LD
10 m
24761 Ahau
Jan. 11
70.8 LD
1.4 km
2000 YH66
Jan. 12
69.5 LD
1.1 km
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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