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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: 384.5 km/s
0.5 protons/cm3
explanation | more data
Updated: Today at 2245 UT

X-ray Solar Flares

6-hr max:
A5 2105 UT Jan04
24-hr: A9 0945 UT Jan04
explanation | more data
Updated: Today at 2245 UT

Daily Sun: 04 Jan '06

These sunspots do not pose a threat for strong solar flares. Credit: SOHO/MDI

Sunspot Number: 39
What is the sunspot number?
Updated: 03 Jan 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: 5.0 nT
2.6 nT north
explanation | more data
Updated: Today at 2246 UT

Coronal Holes:

There are no large coronal holes on the sun today. Image credit: SOHO Extreme UV Telescope.


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 Jan 04 2204 UTC
FLARE 0-24 hr 24-48 hr
CLASS M 01 % 01 %
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 Jan 04 2204 UTC
0-24 hr 24-48 hr
ACTIVE 10 % 10 %
MINOR 05 % 05 %
SEVERE 01 % 01 %

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

What's Up in Space -- 4 Jan 2006
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The space station is visible in the night sky this month. Would you like to see it? Sign up for SpaceWeather PHONE.

AURORA MEGA-GALLERY: Have you ever wondered what it would be like to fly through the aurora borealis? Can you see auroras from Florida? Is there a season for geomagnetic storms? Answers await in the new Aurora Mega-Gallery.

EARTH AT PERIHELION: Don't look, but the Sun is bigger than usual this week. That's because Earth is at perihelion. Earth's orbit is not a perfect circle, it is an ellipse. Our distance from the Sun therefore varies throughout the year. Perihelion is the least distance: 147 million km on Jan. 4th.

For comparison, aphelion is the greatest distance: 152 million km on July 4th. The picture above, contributed by Anthony Ayiomamitis of Athens, Greece, shows how the sun's apparent diameter varies throughout the year. He took the pictures on the dates of aphelion and perihelon 2005. [more]

VENUSIAN RAINBOW: Venus is hanging low in the sunset sky: map. Amateur astronomers who've looked at it lately have noticed something extraordinary: Venus looks like a rainbow. This picture comes from Ron Wayman of Tampa, Florida:

Venus on Jan. 3rd, seen through an 8-inch telescope.

Venus has phases, and at the moment it is a crescent. That explains the shape. But what about the colors?

Atmospheric optics expert Les Cowley has the answer: "Our atmosphere is curved around the Earth and acts as a huge lens," he explains. "It bends the rays from objects close to the horizon so that they appear higher in the sky than they actually are. Blue and green light are bent more than red light. The result: the blue/green image of Venus rides highest in the sky while the red image hangs lowest, producing an upper blue/green rim and a lower red rim. Our giant lens is also unsteady and sometimes we see Venus rippling and flashing all the colors of the rainbow."

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 4 Jan 2006 there were 755 known Potentially
Hazardous Asteroids

January 2006 Earth-asteroid encounters




2005 XO4

Jan. 1

18.5 LD


~150 m
2005 YM128

Jan. 1

19.8 LD


~75 m
2005 YO128

Jan. 3

6.5 LD


~60 m
2005 YU8

Jan. 13

19.8 LD


~70 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. See also Snow Crystals.

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 --a gallery of up-to-date solar pictures from the National Solar Data Analysis Center at the Goddard Space Flight Center. See also the GOES-12 Solar X-ray Imager.

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

SOHO Farside Images of the Sun from SWAN and MDI.

The Latest SOHO Coronagraph Images -- from the Naval Research Lab

The Sun from Earth -- daily images of our star from the Big Bear Solar Observatory

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

Observable Comets -- from the Harvard Minor Planet Center.

What is the Interplanetary Magnetic Field? -- A lucid answer from the University of Michigan. See also the Anatomy of Earth's Magnetosphere.

Real-time Solar Wind Data -- from NASA's ACE spacecraft. How powerful are solar wind gusts? Read this story from Science@NASA.

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

Aurora Forecast --from the University of Alaska's Geophysical Institute

Lists of Coronal Mass Ejections -- from 1998 to 2001

Mirages: Mirages in Finland; An Introduction to Mirages;

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

Space Audio Streams: (University of Florida) 20 MHz radio emissions from Jupiter: #1, #2, #3, #4; (NASA/Marshall) INSPIRE: #1; (Stan Nelson of Roswell, New Mexico) meteor radar: #1, #2;

Recent International Astronomical Union Circulars


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

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