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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 570.5 km/sec
density: 1.6 protons/cm3
explanation | more data
Updated: Today at 2245 UT
X-ray Solar Flares
6-hr max: A3
2000 UT Jul11
24-hr: B7
1205 UT Jul11
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 11 July 07
Sunspot 963 poses a threat for M-class solar flares. Credit: SOHO/MDI
Sunspot number: 25
What is the sunspot number?
Updated 10 July 2007
Far side of the Sun:
This holographic image reveals no large sunspots on the farside of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 5
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Updated: 2007 Jul 11 2125 UT
Interplanetary Mag. Field
Btotal: 3.2 nT
Bz: 2.3 nT north
explanation | more data
Updated:Today at 2246 UT
Coronal Holes:
Earth is inside a solar wind stream flowing from the indicated coronal hole. Credit: SOHO Extreme Ultraviolet Telescope
NOAA Forecasts
Updated at: 2007 Jul 11 2203 UTC
0-24 hr
24-48 hr
01 %
01 %
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 Jul 11 2203 UTC
0-24 hr
24-48 hr
30 %
10 %
15 %
05 %
05 %
01 %
High latitudes
0-24 hr
24-48 hr
35 %
15 %
25 %
05 %
10 %
01 %
What's up in Space
July 11, 2007
Where's Saturn? Is that a UFO--or the ISS? What's the name of that star? Get the answers from mySKY--a fun new astronomy helper from Meade.

AURORA BOREALIS: Last night a solar wind stream hit Earth sparking a mild geomagnetic storm and auroras as far south as Montana: gallery. Earth is still inside the stream, but the storm has subsided and more auroras are unlikely tonight.

SUNSPOT ARCHIPELAGO: Dynamic sunspot 963 has morphed into "a beautiful sunspot archipelago," says John Stetson of South Portland, Maine. Yesterday, working with students S. Dall and B. Morrissette, he snapped this picture:

The islands in the chain are as big as planets: the large leading spot is about as wide as Neptune while the others range in size from Mars to Earth. Magnetic fields connecting the leader to the trailers are unstable and crackling with C-class solar flares. It's a good show.

UPDATE: This morning in Brazil, Rogerio Marcon used his Coronado SolarMax40 to catch the sunspot in mid-flare: photo.

more images: from Didier Favre of Brétigny sur Orge, France; from Pete Lawrence of Selsey, West Sussex, UK; from Howard Eskildsen of Ocala, Florida; from John C McConnell of Maghaberry Northern Ireland; from Curtasu Mihai of Bucharest, Romania; from Pavol Rapavy of Rimavska Sobota, Slovakia; from Ettore Ruga of Italy; from Michel Hersen of Portland, Oregon; from David Lerner of Monmouth Junction, NJ;

COMET LINEAR VZ13: On July 11th, Comet Linear VZ13 glides by Edasich, a 3rd magnitude star in the constellation Draco. Also known as iota Draconis, this star is best known for its big planet, a giant world 9 times more massive than Jupiter. Tonight, consider it a guidestar to the comet. [sky map] [3D orbit] [ephemeris]

At 8th magnitude, Linear VZ13 is too dim for the naked eye, but it materializes readily enough as a charming fuzzball in binoculars. And "it is an easy target for backyard telescopes of all sizes," reports John Chumack who sends this picture from his observatory in Yellow Springs, Ohio:

Photo details: 16-inch Newtonian telescope, SBIG ST9 CCD, 2 min. exposure

"It has a large coma and a very bright stellar nucleus," notes Chumack. "The comet's tail, however, is small and faint."

What makes the comet's atmosphere (coma) green? Answer: The coma contains cyanogen (CN), a poisonous gas, and diatomic carbon (C2). Both of these substances glow green when illuminated by sunlight--a process called "resonant fluorescence."

more images: ; from Günther Strauch of Borken, NRW, Germany; from Vincent Jacques of Breil, France; from Stanescu Octavian of Silagiu, Romania; from Dalibor Hanžl of Brno, Czech Republic; from Doug Zubenel of De Soto, Kansas.

2007 Noctilucent Cloud Gallery
["Noctilucent Cloud"--the song] [Night-Sky Cameras]

Near-Earth Asteroids
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 July 11, 2007 there were 874 potentially hazardous asteroids.
July 2007 Earth-asteroid encounters:
Miss Distance
2007 FV42
July 2
53 LD
1.2 km
2007 MB4
July 4
7.6 LD
130 m
2007 DT103
July 29
9.3 LD
550 m
Notes: LD means "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 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.
Daily Sunspot Summaries
  From the NOAA Space Environment Center
Current Solar Images
  from the National Solar Data Analysis Center
  more links...
©2007, -- This site is penned daily by Dr. Tony Phillips.
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