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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: 304.4 km/s
1.7 protons/cm3
explanation | more data
Updated: Today at 2245 UT

X-ray Solar Flares

6-hr max:
B2 1650 UT Apr30
24-hr: C5 0155 UT Apr30
explanation | more data
Updated: Today at 2245 UT

Daily Sun: 30 Apr '06

Sunspot 875 is decaying, but it still poses a threat for M-class solar flares. Credit: SOHO/MDI.

Sunspot Number: 64
What is the sunspot number?
Updated: 29 Apr 2006

Far Side of the Sun

This holographic image reveals one mid-sized spot on the far side of the sun. Image credit: SOHO/MDI

Interplanetary Mag. Field
Btotal: 3.2 nT
2.5 nT north
explanation | more data
Updated: Today at 2246 UT

Coronal Holes:

A solar wind gust flowing from the indicated coronal hole could reach Earth on May 5th or 6th. 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 30 2204 UTC
FLARE 0-24 hr 24-48 hr
CLASS M 25 % 25 %
CLASS X 05 % 05 %

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 30 2204 UTC
0-24 hr 24-48 hr
ACTIVE 10 % 20 %
MINOR 05 % 10 %
SEVERE 01 % 05 %

High latitudes
0-24 hr 24-48 hr
ACTIVE 15 % 20 %
MINOR 05 % 15 %
SEVERE 01 % 05 %

What's Up in Space -- 30 Apr 2006
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Roses. Candy. Spatulas? Make that the stars: Spaceweather PHONE for Mother's Day.

SUN SOUNDS: Sunspot 875 is decaying, but it continues to produce C-class solar flares and shortwave radio bursts. Thomas Ashcraft is recording the sounds using a radio telescope in New Mexico: listen.

EARTHSHINE: A crescent Moon with Earthshine is one of the prettiest sights in the heavens. See for yourself this evening when the crescent Moon pops out of the western twilight at sunset.

Click to view the complete 4 MB movie

Above: "Note the increased effect of Earthshine as the Moon approaches the horizon," says photographer Thad V'Soske who took these pictures from the Colorado National Monument on April 29th.

more images: from John Stetson of Falmouth, Maine; from Denis Joye near Paris, France; from Shahrin of Teluk Kemang, Malaysia;

SUN HALO: "Winter has lingered so long here in central California that we have had virtually no views of the disintegrating comet or anything else in the night sky," says Andy Skinner of Mariposa, California. "However, there have been sun halos for days and days." He photographed this one on April 25th:

Sun halos are caused by tiny ice crystals in high cirrus clouds. The crystals catch the rays of the sun and bend them into a rainbow-colored circle 22 degrees in radius. Winter is not required: it's always cold enough for ice crystals to form 10 km above the ground where cirrus clouds float.

*Solar Chat*

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 30 Apr 2006 there were 784 known Potentially
Hazardous Asteroids

May 2006 Earth-asteroid encounters




2006 HU50

May 4

3.8 LD


Comet 73P-C

May 12

31 LD


~1 km
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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