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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: 440.8 km/s
5.7 protons/cm3
explanation | more data
Updated: Today at 2246 UT

X-ray Solar Flares

6-hr max:
B3 2050 UT Apr28
24-hr: C1 0825 UT Apr28
explanation | more data
Updated: Today at 2245 UT

Daily Sun: 28 Apr '06

Sunspot 875 has a "beta-gamma" magnetic field that harbors energy for M-class solar flares. Credit: SOHO/MDI.

Sunspot Number: 63
What is the sunspot number?
Updated: 27 Apr 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: 5.3 nT
4.7 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 today. 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 Apr 28 2203 UTC
FLARE 0-24 hr 24-48 hr
CLASS M 20 % 20 %
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 Apr 28 2203 UTC
0-24 hr 24-48 hr
ACTIVE 10 % 10 %
MINOR 01 % 01 %
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 -- 28 Apr 2006
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Roses. Candy. Spatulas? Make that the stars: Spaceweather PHONE for Mother's Day.

REMEMBER SUITSAT? Three months ago, ISS astronauts hurled an old Russian spacesuit overboard. Amazingly, it is still orbiting Earth. On April 18th, Kevin Fetter videotaped "SuitSat" passing over his home in Brockville, Ontario, Canada: 1 MB movie. (The bright star in the movie is Vega.) Eventually, SuitSat will sink into Earth's atmosphere and disintegrate in spectacular style--a fireball--but not yet!

RADIO BLACKOUT: Yesterday's strong M8-flare from sunspot 875 caused a shortwave radio blackout on Earth. Antennas at the University of Florida Radio Observatory recorded the event in the form of a dynamic spectrum, below. Horizontal lines on the left are radio stations. On the right they vanish, silenced by the flare for more than 10 minutes:

Image Credit: Thomas Ashcraft and the UFRO

How does a solar flare cause a radio blackout? X-rays from solar flares knock electrons from atoms and molecules in Earth's atmosphere. Once free, these electrons can steal energy from radio waves, quenching them.

Some of yesterday's lesser flares produced radio waves of their own. Thomas Ashcraft of New Mexico recorded the sounds using an antenna tuned to 22 MHz: listen.

COMET NEWS: Dying comet 73P/Schwassmann Wachmann 3 is falling apart with a vengeance. Even the fragments are fragmenting. Astronomers using the Hubble Space Telescope took this picture of Fragment B--and entourage--on April 18th:

Good news: You don't need the Hubble to watch these events. As the comet crumbles, fresh veins of ice and dust are exposed to sunlight, causing the pieces to brighten. Fragment B now glows like an 8th magnitude star and is an easy target for backyard telescopes. Look for it in the constellation Corona Borealis an hour or so after sunset: sky map.

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 28 Apr 2006 there were 778 known Potentially
Hazardous Asteroids

April-May 2006 Earth-asteroid encounters




2006 GY2

May 16

6.7 LD


~0.8 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. 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

Daily images from the sun -- 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.

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; 2005; Jan-Mar 2006;

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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