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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: 272.2 km/s
3.4 protons/cm3
explanation | more data
Updated: Today at 2246 UT

X-ray Solar Flares
6-hr max:
A0 1825 UT Mar21
24-hr: A0 1255 UT Mar21
explanation | more data
Updated: Today at 2245 UT

Daily Sun: 21 Mar '07

The sun is blank today--no sunspots. Credit: SOHO/MDI

Sunspot Number: 0
What is the sunspot number?
Updated: 20 Mar 2007

Far Side of the Sun

This holographic image reveals a possible sunspot group on the far side of the sun. Image credit: SOHO/MDI

Interplanetary Mag. Field
Btotal: 1.3 nT
1.1 nT south
explanation | more data
Updated: Today at 2247 UT

Coronal Holes:

A solar wind stream flowing from this coronal hole could reach Earth on March 24th. 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 2007 Mar 21 2203 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 2007 Mar 21 2203 UTC
0-24 hr 24-48 hr
ACTIVE 15 % 20 %
MINOR 05 % 05 %
SEVERE 01 % 01 %

High latitudes
0-24 hr 24-48 hr
ACTIVE 15 % 25 %
MINOR 05 % 10 %
SEVERE 01 % 01 %

What's Up in Space -- 21 Mar 2007
Subscribe to Space Weather News

The space shuttle flies in April. Would you like a call when it soars over your backyard? Spaceweather PHONE!

AURORA SPRING: Today is the first day of northern spring--a.k.a. the "vernal equinox." This is good news for sky watchers because, statistically speaking, equinoxes are the best times of year to spot auroras. A solar wind stream is due to hit Earth on March 24th, so stay tuned for Northern Lights.

BONUS: Inspired by the coming of spring, artist Mark Siebold created a pastel interpretation of Earth's 23.5 degree tilt. The reason for seasons has never been so beautiful.

VENUS AND THE MOON: Actually, her name is Sabine. "Last night, my girlfriend posed for this shot on the beach at La Torche," explains French photographer Laurent Laveder. "I call it Moon Temple Guardian."

Photo details: Canon 30D, Sigma 70-300mm lens, 1/4 s.

Sabine and Laurent had lots of fun with the crescent Moon; they caught it in a net, lassooed it, and threw it like a boomerang. Click here for a gallery of images.

Tonight at sunset, the crescent Moon will appear again hovering just above the planet Venus: sky map. What will you do?

CHROMOSPHERE SURPRISE: It's enough to make you leap out of your seat: A magnetic vortex almost as big as Earth races across your computer screen, twisting, turning, finally erupting in a powerful solar flare. Japan's Hinode spacecraft recorded just such a blast on Jan. 12, 2007. Click on the image to see the movie:

Above: An H-alpha image of the sun from Japan's Hinode spacecraft.

The footage is visually stunning, but the most surprising thing is where the scene unfolds--in the solar chromosphere, a layer of the sun's atmosphere previously thought to be relatively uneventful. Get the full story from Science@NASA.

March 19th Solar Eclipse Gallery
Updated March 20, 2007

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 21 Mar 2007 there were 853 known Potentially
Hazardous Asteroids

March 2007 Earth-asteroid encounters




2007 EH

Mar. 11

0.5 LD


10 m
2007 EK

Mar. 13

0.7 LD


5 m
2006 VV2

Mar. 31

8.8 LD


2 km
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

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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