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

X-ray Solar Flares

6-hr max:
A9 2130 UT May18
24-hr: A9 2130 UT May18
explanation | more data
Updated: Today at 2245 UT

Daily Sun: 18 May '06

There are no spots on the sun today, Solar minimum is here. Credit: SOHO/MDI.

Sunspot Number: 0
What is the sunspot number?
Updated: 17 May 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: 7.8 nT
5.7 nT north
explanation | more data
Updated: Today at 2247 UT

Coronal Holes:

A solar wind stream flowing from the indicated coronal hole should reach Earth on May 20th or 21st. 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 May 18 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 2006 May 18 2204 UTC
0-24 hr 24-48 hr
ACTIVE 25 % 20 %
MINOR 10 % 10 %
SEVERE 01 % 01 %

High latitudes
0-24 hr 24-48 hr
ACTIVE 35 % 25 %
MINOR 20 % 10 %
SEVERE 10 % 01 %

What's Up in Space -- 18 May 2006
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SOLAR WIND: Earth is entering a solar wind stream. The encounter could cause a geomagnetic storm and auroras over Alaska and Canada. Northern sky watchers, pay attention!

SOLAR ACTIVITY: The sunspot number is zero, but that doesn't mean solar activity is zero. John Stetson of Falmouth, Maine, photographed an enormous prominence erupting on May 17th:

Above: The sun viewed through a Coronado solar telescope.

How big is it? If you placed one end of the glowing filament on Earth, the other end would stretch almost to the Moon. Because of its location near the sun's limb, the eruption did not fling any material toward Earth. That's the best kind of solar activity: Pretty, with no harmful side effects.

more images: from Greg Piepol of Rockville, Maryland; from Adrian Guzman of San Jose, California.

DEWBOW: Not all rainbows are in the sky. Look carefully at this field of grass photographed on May 9th by Laurent Laveder of Chateaulin, Brittany, France. Can you see the rainbow running faintly down the middle?

"Dewbow" would be a better name for it, says Laveder. He's right. This rainbow is caused by dew. Little droplets of water hanging on to blades of grass catch the rays of the morning sun, spreading them into the colors you know so well. (True rainbows are formed in the same way, only the droplets are up in the air.)

In a second picture, Laveder caught a strange halo around the head of his shadow. This is caused by dew, too. It's called heiligenschein.

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 18 May 2006 there were 786 known Potentially
Hazardous Asteroids

May 2006 Earth-asteroid encounters




2006 HU50

May 4

3.8 LD


~50 m
2006 HX57

May 6

3.0 LD


~45 m
2006 JY26

May 10

1.1 LD


~8 m
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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