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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: 308.8 km/s
4.1 protons/cm3
explanation | more data
Updated: Today at 2246 UT

X-ray Solar Flares
6-hr max:
A0 2025 UT Mar20
24-hr: A1 1155 UT Mar20
explanation | more data
Updated: Today at 2245 UT

Daily Sun: 20 Mar '07

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

Sunspot Number: 0
What is the sunspot number?
Updated: 19 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: 3.1 nT
0.0 nT
explanation | more data
Updated: Today at 2247 UT

Coronal Holes:

A solar wind stream flowing from the indicated coronal hole could reach Earth on March 22nd. 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 20 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 20 2203 UTC
0-24 hr 24-48 hr
ACTIVE 15 % 15 %
MINOR 01 % 01 %
SEVERE 01 % 01 %

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

What's Up in Space -- 20 Mar 2007
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The space shuttle flies in April. Would you like a call when it soars over your backyard? Spaceweather PHONE!

VENUS AND THE MOON: When the sun goes down tonight, step outside and look west. You'll see Venus and the slender crescent Moon beaming together through the glow of sunset--beautiful!

ECLIPSE MIRAGE: What do you get when you combine a solar eclipse with a temperature inversion? Answer--a very strange Alaskan sunset. James Helmericks took this picture from the Colville River Delta of Alaska's North Slope on March 18th:

Photo details: Canon 300D, 400mm, 1/1000, f5.6

The crescent shape of the sun is caused by a partial eclipse--the Moon passed off-center in front of the sun on March 18th and 19th. This was widely seen from India, China, and the northern reaches of Alaska. The rest is a mirage....

"Alaska is the place for strong mirages," explains atmospheric optics expert Les Cowley. "Often, layers of very cold air sit beneath warmer layers. Here the abnormal refraction has produced a distorted and strongly flattened partially eclipsed sun. The miraging temperature inversion layers can be seen crossing the sun and at each side."

"Conditions like these often produce green flashes," he adds, but so far no one has reported a flash to go with this eclipse. Photos welcomed!

March 19th Solar Eclipse Gallery
Updated March 20, 2007

NEW COMET LOVEJOY: On March 15th, Terry Lovejoy of Thornlands, Australia, discovered a new comet (C/2007 E2) in the southern constellation Indus. Remarkably, to make the find he used not a telescope but just an off-the-shelf digital camera--a Canon 350D. At Lovejoy's request, John Drummund of Gisborne, New Zealand, confirmed the comet with this photo taken through a 0.41-m reflector:

Photo details:
16" Newtonian @f5.2, SBIG STL11000M CCD, 3 minutes

The new comet is green and shines like a 9th magnitude star, too dim for the unaided eye but an easy target for large backyard telescopes in the southern hemisphere: ephemeris.

After five days of tracking, Comet Lovejoy's trajectory is known. The orbit is cockeyed, almost perpendicular to the rest of the solar system. At the moment the comet is swooping up from below, moving from southern to northern skies. At closest approach to Earth (0.44 AU) in late April, Comet Lovejoy is expected to brighten to 7th magnitude, still not a naked-eye comet but easy to see through small telescopes.

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 20 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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