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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: 297.6 km/s
0.9 protons/cm3
explanation | more data
Updated: Today at 2245 UT

X-ray Solar Flares
6-hr max:
B1 2220 UT May13
24-hr: B1 2220 UT May13
explanation | more data
Updated: Today at 2245 UT

Daily Sun: 13 May '07

Sunspot 955 is poses no threat for strong solar flares. Credit: SOHO/MDI

Sunspot Number: 21
What is the sunspot number?
Updated: 12 May 2007

Far Side of the Sun

This holographic image reveals no sunspots on the farside of the sun, mage credit: SOHO/MDI

Interplanetary Mag. Field
Btotal: 1.6 nT
0.9 nT south
explanation | more data
Updated: Today at 2245 UT

Coronal Holes:

A solar wind stream flowing from the indicated coronal hole will reach Earth on or about May 18th. 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 2007 May 13 2203 UTC
FLARE 0-24 hr 24-48 hr
CLASS M 05 % 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 2007 May 13 2203 UTC
0-24 hr 24-48 hr
ACTIVE 15 % 15 %
MINOR 05 % 05 %
SEVERE 01 % 01 %

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

What's Up in Space -- 13 May 2007
Subscribe to Space Weather News

What's the name of that star? Where's Saturn? Get the answers from mySKY--a fun new astronomy helper from Meade.

MERCURY RISING: Tonight when the sun sets, step outside, face west, and look for Mercury hanging just above the tree tops. Elias Chasiotis of Markopoulo, Greece, snapped this picture on May 12th. "Mercury is brighter than magnitude -1 and visible to the naked eye," he reports. Can't find it? Wait a few days. Mercury is emerging from the sun's glare, making itself easier to find with each passing night in May.

CALCIUM STAR: The sun is made mainly of hydrogen (73%) and helium (25%), but there are small amounts of other things, too, such as calcium (0.003%), the element of human bone! If you could see the sun's calcium, what would it look like? Larry Alvarez provides the answer with this picture taken yesterday from his home in Flower Mound, Texas:

Photo details: Coronado 70mm Calcium CaK telescope and Lumenera ccd.

He captured the image using a CaK filter tuned to the violet glow of singly-ionized calcium. "I pumped up the gain on my ccd detector and was able to image beautiful flowing fountains of plasma on the edge of the solar disk," he says. "The view was amazing."

GREEN COMET: Comet Lovejoy (C/2007 E2) is not quite bright enough to see with the unaided eye, but the sea-green comet is a lovely sight through backyard telescopes. Using a 6-inch refractor, John Chumack took this picture last night:

"Several little galaxies are visible in the background," notes Chumack. "Look below the comet's tail."

Comet Lovejoy enjoys minor fame for the method of its discovery. Australian Terry Lovejoy found it two months ago using no telescope, only a digital camera (a Canon 350D). The comet's green head, glowing about as brightly as an 8th magnitude star, is one and a half times wider than the giant planet Jupiter. This comet is big!

You can find Comet Lovejoy this week gliding through the constellation Draco, high in the northern sky after sunset. A good night is May 14th when Lovejoy passes right by the 2nd magnitude star eta Draconis. The star will guide you to the comet. Sky maps: May 12, 13, 14, 15.

more images: from Mike Holloway of Van Buren, Arkansas

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 13 May 2007 there were 861 known Potentially
Hazardous Asteroids

April 2007 Earth-asteroid encounters




2007 DS84

Apr. 14

16 LD


325 m
2007 GU1

Apr. 16

2.1 LD


45 m
2007 HA

Apr. 17

6.5 LD


300 m
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.

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 -- from the National Solar Data Analysis Center

Recent Solar Events -- a summary of current solar conditions from

What is the Magnetosphere?

The Lion Roars -- visit this site to find out what the magnetosphere sounds like.

List of Potentially Hazardous Asteroids -- from the Harvard Minor Planet Center.

Observable Comets -- from the Harvard Minor Planet Center.

Real-time Solar Wind Data -- from NASA's ACE spacecraft.

How powerful are solar wind gusts? Not very! 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 1996 to 2006

Mirages: Mirages in Finland; An Introduction to Mirages;

NOAA Solar Flare and Sunspot Data: 1994, 1995, 1996, 1997, 1998, 1999; 2000; 2001; 2002; 2003; 2004; 2005; Jan-Mar 2006; Apr-Jun 2006; Jul-Sep 2006; Oct-Dec 2006.

This site is penned daily by Dr. Tony Phillips: email

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