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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Science news and information about the Sun-Earth environment.


Solar Wind
speed: 317.8 km/s
3.3 protons/cm3
explanation | more data
Updated: Today at 2246 UT

X-ray Solar Flares
6-hr max:
A6 2050 UT Dec31
24-hr: C1 0715 UT Dec31
explanation | more data
Updated: Today at 2245 UT

Daily Sun: 31 Dec '06

Sunspot 930, the source of four X-flares in mid-December, has returned. Note: NOAA has renumbered this sunspot 933. Credit:

Sunspot Number: 11
What is the sunspot number?
Updated: 30 Dec 2006

Far Side of the Sun

This holographic image reveals no large sunspots on the far side of the sun. Image credit: SOHO/MDI

Interplanetary Mag. Field
Btotal: 4.7 nT
2.8 nT south
explanation | more data
Updated: Today at 2247 UT

Coronal Holes:

A solar wind stream flowing from the indicated coronal hole should hit Earth on Jan. 2nd. Credit: GOES-13 Solar X-ray Imager.


Solar Flares: Probabilities for a medium-sized (M-class) or a major (X-class) solar flare during the next 24/48 hours are tabulated below.
Updated at 2006 Dec 31 2203 UTC
FLARE 0-24 hr 24-48 hr
CLASS M 05 % 05 %
CLASS X 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 2006 Dec 31 2203 UTC
0-24 hr 24-48 hr
ACTIVE 10 % 30 %
MINOR 05 % 15 %
SEVERE 01 % 05 %

High latitudes
0-24 hr 24-48 hr
ACTIVE 15 % 40 %
MINOR 05 % 20 %
SEVERE 01 % 10 %

What's Up in Space -- 31 Dec 2006
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Did you sleep through the auroras of Dec. 14th? Next time get a wake-up call: Spaceweather PHONE.

IT'S BACK: Sunspot 930, which unleashed four X-flares and sparked intense auroras in mid-December, is back. It is emerging over the sun's eastern limb following a two-week transit around the far side of the sun. Since we last saw it, the spot has probably decayed and now poses little threat for strong solar flares. Stay tuned for confirmation.

HAPPY NEW YEAR: 2006 was a good year for space weather: bright auroras, backward sunspots, powerful flares. Click on the image below to browse some of the highlights.

Image credit: Greg Piepol of Rockville, Maryland.

Next year should be even better. 2006 was a year of solar minimum, a low point at the end of Solar Cycle 23. 2007 should bring the first stirrings of Solar Cycle 24, predicted to be one of the biggest in history. There's a lot to look forward to.... Happy New Year!

DARK CLOUDS: Four hundred years ago, astronomers thought sunspots might be dark clouds in the sun's atmosphere. Galileo proved otherwise. By tracking the motions of sunspots, he showed that they were not clouds but islands (of magnetism) on the sun's surface. Case closed.

Except for one thing: There are dark clouds in the sun's atmosphere. Eric Roel of Valle de Bravo, Mexico, photographed one yesterday:

Photo details: SolarMax40, 76mm TeleVue, f/6.3.

It's called a filament--a hundred-thousand-mile long cloud of hydrogen held above the sun's surface by magnetic force fields. Filaments existed 400 years ago, but Galileo couldn't see them because he didn't have a filter tuned to the deep-red glow of solar hydrogen.

This filament is moving toward the sun's western horizon, where it will vanish a few days from now. If you have a solar telescope, take a look before it goes. You might see something Galileo never did.

BONUS: December Aurora Gallery
updated Dec. 28, 2006

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 31 Dec 2006 there were 831 known Potentially
Hazardous Asteroids

Dec 2006 Earth-asteroid encounters




2006 WQ127

Dec. 2

7.9 LD


~94 m
2006 WB

Dec. 5

7.0 LD


~130 m
2004 XL14

Dec. 20

10.1 LD


~225 m
2006 XD2

Dec. 24

10.7 LD


~260 m
Notes: LD is a "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 Web Links

NOAA Space Environment 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. (European Mirror Site)

Daily Sunspot Summaries -- from the NOAA Space Environment Center.

Current Solar Images -- from the National Solar Data Analysis Center

X-ray images of the Sun: GOES-12 and GOES-13

Recent Solar Events -- a summary of current solar conditions from

What is the Magnetosphere?

The Lion Roars -- visit this site to find out what the magnetosphere sounds like.

List of Potentially Hazardous Asteroids -- from the Harvard Minor Planet Center.

Observable Comets -- from the Harvard Minor Planet Center.

Real-time Solar Wind Data -- from NASA's ACE spacecraft.

How powerful are solar wind gusts? Not very! Read this story from Science@NASA.

More Real-time Solar Wind Data -- from the Solar and Heliospheric Observatory Proton Monitor.

Lists of Coronal Mass Ejections -- from 1996 to 2006

Mirages: Mirages in Finland; An Introduction to Mirages;

NOAA Solar Flare and Sunspot Data: 1994, 1995, 1996, 1997, 1998, 1999; 2000; 2001; 2002; 2003; 2004; 2005; Jan-Mar 2006; Apr-Jun 2006; Jul-Sep 2006; Oct-Dec 2006.

This site is penned daily by Dr. Tony Phillips: email

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