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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: 666.2 km/s
2.7 protons/cm3
explanation | more data
Updated: Today at 2247 UT

X-ray Solar Flares

6-hr max:
B4 2235 UT Mar21
24-hr: C1 1425 UT Mar21
explanation | more data
Updated: Today at 2245 UT

Daily Sun: 21 Mar '03
Sunspot 314 has decayed. It now has a beta-gamma magnetic field that harbors energy for M-class solar flares. Image credit: SOHO/MDI

The Far Side of the Sun

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

Sunspot Number: 45
What is the sunspot number?
Updated: 20 Mar 2003

Coronal Holes:

Solar wind gusts from the indicated coronal hole could buffet Earth's magnetic field as early as March 25th. Image credit: SOHO Extreme UV Telescope.
More about coronal holes

Interplanetary Mag. Field
Btotal: 8.2 nT
3.2 nT south
explanation | more data
Updated: Today at 2247 UT


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 2003 Mar 21 2200 UTC
FLARE 0-24 hr 24-48 hr
CLASS M 10 % 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 2003 Mar 21 2200 UTC
0-24 hr 24-48 hr
ACTIVE 25 % 20 %
MINOR 10 % 10 %
SEVERE 05 % 05 %

High latitudes
0-24 hr 24-48 hr
ACTIVE 35 % 30 %
MINOR 15 % 10 %
SEVERE 10 % 05 %

What's Up in Space -- 21 Mar 2003
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MARCH EQUINOX: The Sun, heading north in the sky, crosses the celestial equator on March 21st at 01:00 UT. This marks the beginning of spring in the northern hemisphere and the beginning of fall in the southern hemisphere. Day and night will be of approximately equal length on March 21st--hence the name equinox, which means "equal night."

ANALEMMA: If you took a picture of the Sun at the same time each day, would it remain in the same position? The answer is no, and the figure-8 shape traced out by the Sun over the course of a year is called an analemma. (continued below)

This analemma was recorded by Anthony Ayiomamitis of Athens, Greece. Using a single piece of film, he photographed the rising Sun on 38 mornings between January and December 2002. He completed the picture with a single exposure of the Tholos--a mysterious Greek ruin from 380 B.C.

The upper and lower tips of the "8" represent the solstices--the longest and shortest days of the year. Equinoxes (such as today) lie on the analemma exactly midway between the tips. [more]

AURORA WATCH: Earth remains inside a high-speed solar wind stream for the 7th day in a row. Sky watchers should be alert for auroras after local nightfall on March 21st. The best viewing sites would be at high-latitudes: e.g., New Zealand, southern Australia, Canada, northern Europe, Alaska and northern continental US states like Michigan and Wisconsin.

Above: Try as it might, the Moon couldn't overwhelm these bright auroras over Alaska on March 19th. Image credit: Chuck Johnson, Cleary Summit Bed & Breakfast. [gallery]


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 are on a collision course with our planet, although astronomers are finding new ones all the time.

On 21 Mar 2003 there were 498 known Potentially
Hazardous Asteroids

March 2003 Earth-asteroid encounters


2003 DW10

 Mar. 3

1.4 LD

2003 ED50

 Mar. 19

26 LD

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.

  • LEONIDS 2002: The Leonids have come and gone, but our meteor gallery keeps growing. Check out the latest additions, which include a stunning image of 44 meteors emerging from the radiant in Leo.
  • DAWN PLANETS: Just before dawn on Sunday, Dec. 1st, the planets Venus and Mars converged and formed a lovely triangle with the slender crescent Moon. [gallery]
  • SUMMER AURORAS: August was a good month for auroras. Visit our gallery and see what happened in the skies of Europe and North America.
  • NEARBY ASTEROID: Asteroid 2002 NY40 came so close to Earth on August 18th that people could see it through binoculars or small telescopes. [gallery]
  • PERSEIDS 2002: Sky watchers spotted plenty of bright shooting stars--including some colorful earthgrazers--during the 2002 Perseid meteor shower. [gallery]
  • AURORA SURPRISE: An unexpected geomagnetic storm began on August 1st as night fell across North America. Sky watchers spotted vivid auroras over both the United States and Canada.
  • CRESCENT SUN: See strange shadows, weird sunsets, eclipse dogs, crescent-eyed turkeys and extraordinary rings of fire photographed during the June 10th solar eclipse. [gallery]
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.

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.

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.

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

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

Daily Solar Flare and Sunspot Data -- from the NOAA Space Environment Center.

Lists of Coronal Mass Ejections -- from 1998 to 2001
What is an Iridium flare?

Vandenberg AFB missile launch schedule.

What is an Astronomical Unit, or AU?

Mirages: Mirages in Finland; An Introduction to Mirages;

NOAA Solar Flare and Sunspot Data: 1999; 2000; 2001; Jan-Mar., 2002; Apr-Jun., 2002; Jul-Sep., 2002; Oct-Dec., 2002;

Recent International Astronomical Union Circulars





Editor's Note: Space weather and other forecasts that appear on this site are formulated by Dr. Tony Phillips. They are not official statements of any government agency (including NASA) nor should they be construed as guarantees of space weather or other celestial activity.

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Dr. Tony Phillips
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