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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: 509.4 km/s
8.0 protons/cm3
explanation | more data
Updated: Today at 2245 UT

X-ray Solar Flares

6-hr max:
A2 1825 UT Sep30
24-hr: A2 1825 UT Sep30
explanation | more data
Updated: Today at 2245 UT

Daily Sun: 30 Sep '05

These sunspots pose no threat for strong solar flares. Credit: SOHO/MDI

Sunspot Number: 22
What is the sunspot number?
Updated: 29 Sep 2005

Far Side of the Sun

This holographic image reveals on the farside of the sun an old friend: sunspot 798, which sparked bright auroras in August and Sept. 2005. Image credit: SOHO/MDI

Interplanetary Mag. Field
Btotal: 8.7 nT
1.9 nT north
explanation | more data
Updated: Today at 2246 UT

Coronal Holes:

There are no big coronal holes on the Earth-facing side of the sun nthis week. 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 2005 Sep 29 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 2005 Sep 29 2204 UTC
0-24 hr 24-48 hr
ACTIVE 20 % 20 %
MINOR 10 % 10 %
SEVERE 01 % 01 %

High latitudes
0-24 hr 24-48 hr
ACTIVE 30 % 30 %
MINOR 20 % 20 %
SEVERE 05 % 05 %

What's Up in Space -- 30 Sep 2005
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Did you miss the auroras of Sept.? Next time get a phone alert: Sign up for SpaceWeather PHONE.

QUIET SUN: Solar activity is very low. Strong flares and auroras are unlikely this week.

SOLAR ECLIPSE: On October 3rd, the moon will glide in front of the sun, producing a solar eclipse visible from Europe, Africa and the Middle East. The eclipse won't be total, but rather annular, meaning that the moon won't be big enough to completely cover the sun. Observers along the narrow path of annularity (the red line in the map, below) will see a ring of fire encircling the moon--spectacular!

Click to view a full-sized animated map

On either side of the red line, the eclipse will be partial; the sun will look like a crescent--thin near the path of annularity and fat far from it. Fun activity: Look for crescent-shaped sunbeams dappling the ground through the leaves of trees. It works for dogs, too!

MYSTERY RAINBOW: What does it take to make a rainbow? Two things: raindrops and sunlight. Raindrops act like tiny prisms, catching sunbeams and splitting them into their primary colors.

On Sept. 26, Bruno Nolf of Belgium observed something strange: a rainbow with no sun and no rain. "It was a very strange rainbow," says Nolf, who snapped this picture:

"This red rainbow is a mystery because the sun had set four minutes earlier and was well below the horizon," says atmospheric optics expert Les Cowley. "Furthermore, according to Nolf, there was no rain falling and none visible on local weather radar!"

Cowley and colleague Gunther Konnen, a meteorologist, may have an explanation: Thousands of feet above Nolf, the sun had not yet set. (Think about it: "If your flight has ever taken off shortly after sunset you will see the sun rising again as the airplane climbs," notes Cowley.) Somewhere off in the distance, they speculate, a mile-high rainstorm that somehow evaded the radar caught the reddened rays of the setting sun, producing the Bruno's 'bow.

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 30 Sep 2005 there were 710 known Potentially
Hazardous Asteroids

August 2005 Earth-asteroid encounters



1992 UY4

August 8

16 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.

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

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? See also Photographing Satellites by Brian Webb.

What is an Astronomical Unit, or AU?

Mirages: Mirages in Finland; An Introduction to Mirages;

NOAA Solar Flare and Sunspot Data: 1999; 2000; 2001; 2002; 2003; 2004; Jan-Mar., 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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