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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 279.6 km/sec
density: 0.9 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: A8
2120 UT Dec29
24-hr: A8
2120 UT Dec29
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 29 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 28 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 28 Dec 2009

The Radio Sun
10.7 cm flux: 76 sfu
explanation | more data
Updated 28 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= 0
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Interplanetary Mag. Field
Btotal: 2.3 nT
Bz: -0.0 nT
explanation | more data
Updated: Today at 2346 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 29 2241 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 29 2241 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 29, 2009

SATELLITE FLYBYS APP: Turn your iPhone or iPod into a field-tested satellite tracker! presents the Satellite Flybys app.


PARTIAL LUNAR ECLIPSE: On Dec. 31st, the Moon will dip into Earth's shadow for a partial lunar eclipse. The event is visible from Europe, Africa and Asia. At maximum eclipse, around 19:24 UT, approximately 10% of the Moon will be darkly shadowed. [animated preview] [visibility map]

MOON HALO ALERT: It's cold outside. The Moon is waxing full. There's ice in the air. Add them all together and you have perfect conditions for a ring around the Moon:

Photo details: Canon EOS 5D, 8mm fisheye lens, ISO 200, 10s

"I happened to take a stroll outside last night," says photographer David Harvey of Tucson, Arizona. "The Moon was nearly overhead and surrounded by this eye-catching 22o halo."

Such haloes are formed when moonlight passes through pencil-shaped ice crystals floating in high freezing clouds. When you see a 22o moon halo, be alert for moondogs and moon pillars, too. They are formed by plate-shaped ice crystals that often accompany their pencil-shaped cousins.

The Moon is full on Dec. 31st. Mark your calendar for haloes.

more images: from James Helmericks on the Colville River Delta in northern Alaska; from John C McConnell of Maghaberry Northern Ireland; from Jens Hackmann of Bad Mergentheim, Germany; from Gerhard Dangl of Nonndorf, Austria;

SOLAR ACTIVITY: This morning, Dec. 29th, a slow-moving coronal mass ejection (CME) lumbered over the western limb of the sun. A coronagraph onboard the Solar and Heliospheric Observatory (SOHO) recorded the eruption:

Click to launch a 0.9 MB movie

The billion-ton cloud could have come from any of several active regions now on the back side of the sun--namely, former sunspots 1035, 1036 and/or 1038. Earth is not in the cloud's path (and neither is Venus, despite how it looks in the SOHO movie) so the event will not produce any Northern Lights. For auroras, browse the gallery:

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 29, 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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