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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 577.8 km/sec
density: 3.6 protons/cm3
explanation | more data
Updated: Today at 2245 UT
X-ray Solar Flares
6-hr max: B3
1955 UT Dec11
24-hr: B3
1955 UT Dec11
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 11 Dec 07
Sunspot 978 is large but it does not pose a threat for strong solar flares. Credit: SOHO/MDI
Sunspot number: 43
What is the sunspot number?
Updated 10 Dec 2007
Far side of the Sun:
This holographic image shows no large sunspots on the farside of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 3 quiet
24-hr max: Kp= 3
explanation | more data
Current Auroral Oval:

Switch to: Europe, USA, New Zealand, Antarctica
Updated: 2007 Dec 11 2149 UT
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 6.7 nT
Bz: 0.2 nT south
explanation | more data
Updated: Today at 2246 UT
Coronal Holes:
Earth is inside a solar wind stream flowing from the indicated coronal hole. Credit: Hinode X-ray Telescope
NOAA Forecasts
Updated at: 2007 Dec 11 2204 UTC
0-24 hr
24-48 hr
10 %
10 %
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: 2007 Dec 11 2204 UTC
0-24 hr
24-48 hr
30 %
15 %
15 %
05 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
30 %
15 %
15 %
05 %
10 %
01 %

What's up in Space
December 11, 2007
Where's Saturn? Is that a UFO--or the ISS? What's the name of that star? Get the answers from mySKY--a fun new astronomy helper from Meade.

EXPLOSIVE DISCOVERIES: NASA's fleet of THEMIS satellites has made some surprising new discoveries about outbursts of Northern Lights called "substorms" and the source of their power. Findings include giant magnetic ropes that connect Earth to the Sun and explosions in the outskirts of Earth's magnetic field: full story.

NOT A COMET: Last night , sky watchers from England to Florida to Canada witnessed a new exploding comet--or so it seemed. "It looked like Comet Holmes!" says Alvaro Garay of Casselberry, Florida. Chris Schierer of Cazenovia, New York, saw the same thing and "wondered how such a bright naked-eye comet could have been missed." He snapped this picture using a Canon 20D:

A pair of objects streaking through the cloud suggested "a satellite explosion or fuel dump." The latter is correct. This cloud mimicking Comet 17P/Holmes is fuel dumped from the upper stage of an Atlas rocket that launched a classified satellite into orbit for the National Reconnaissance Office on Dec. 10th. The event created a splendid display for about 50 minutes and then faded into the night.

EXTRA: See the fuel dump on video captured by Kevin Fetter of Ontario, Canada.

[Interactive World Map of Fuel Dump Sightings]

SUNSPOT MIRAGE: There's a smudge on this image of yesterday's setting sun, but it's not a defect in photographer Mila Zinkova's camera. "It's sunspot 978," she says.


The enormous spot, along with the rest of the star, was distorted by temperature inversion layers in the air over San Francisco Bay, producing a beautiful mock mirage. "Yet a mirage without a green flash is like a story without the end," notes Zinkova, "and this mirage produced some very bright flashes." A satisfactory end indeed!

more images: from Pete Lawrence of Selsey, West Sussex, UK; from the Hinode spacecraft in Earth orbit; from J. Fairfull and J. Stetson of South Portland, Maine; from John Nassr of Baguio, the Philippines; from James Kevin Ty of Manila, the Philippines; from Javier Temprano of Santander, Spain; from Eric Soucy of Ohain, Belgium; from Ehsan Rostamizadeh of Kerman, Iran;

Comet 17P/Holmes Photo Gallery
[Interactive World Map of Comet Photos]
[sky map] [ephemeris] [3D orbit] [Night Sky Cameras]

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 11, 2007 there were 911 potentially hazardous asteroids.
Dec-Jan Earth-asteroid encounters:
Miss Distance
2007 XZ9
Dec. 1
8.1 LD
45 m
2007 VD184
Dec. 9
7.8 LD
95 m
3200 Phaethon
Dec. 10
47 LD
5 km
2007 TU24
Jan. 29
1.4 LD
405 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 bureau for real-time monitoring of solar and geophysical events, research in solar-terrestrial physics, and forecasting solar and geophysical disturbances.
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.
Daily Sunspot Summaries
  From the NOAA Space Environment Center
Current Solar Images
  from the National Solar Data Analysis Center
  more links...
©2007, -- This site is penned daily by Dr. Tony Phillips.
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