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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 309.2 km/sec
density: 2.6 protons/cm3
explanation | more data
Updated: Today at 2246 UT
X-ray Solar Flares
6-hr max: B7
1850 UT May31
24-hr: C1
1250 UT May31
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 31 May 07
Sunspot 958 is decaying rapidly and poses a diminishing threat for solar flares. Credit: SOHO/MDI
Sunspot number: 12
What is the sunspot number?
Updated 30 May 2007
Far side of the Sun:
This holographic image reveals no large spots on the farside of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 1 Quiet
24-hr max: Kp= 1
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Updated: 2007 May 31 2103 UT
Interplanetary Mag. Field
Btotal: 6.5 nT
Bz: 2.1 nT south
explanation | more data
Updated:Today at 2246 UT
Coronal Holes:
A solar wind stream flowing from the indicated coronal hole should reach Earth on June 2nd or 3rd. Credit: SOHO Extreme Ultraviolet Telescope
NOAA Forecasts
Updated at: 2007 May 31 2203 UTC
0-24 hr
24-48 hr
10 %
10 %
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 31 2203 UTC
0-24 hr
24-48 hr
15 %
15 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
15 %
05 %
05 %
01 %
01 %
What's up in Space
May 31, 2007
He already has a neck tie. This year give Dad something truly heavenly for Father's Day: SpaceWeather PHONE.

BLUE MOON & JUPITER: Tonight's Blue Moon has a companion: Jupiter. All night long, the giant planet will be located right beside the Moon. You can see them with the naked eye or, for a real treat, scan the pair with a backyard telescope. Behold the moons of Jupiter, lunar mountains and craters, and maybe even the Great Red Spot: sky map.

BONUS: Blue Moons are supposed to be absurd, but on May 21st, the Moon over Vecsés, Hungary, really did turn blue. "It was a unique and unforgettable sight," says photographer Ágnes Kiricsi who took these pictures: #1, #2, #3. The display was caused by a Sahara dust storm that filled the air above Hungary with micron-sized dust particles. Clouds of fine dust can act as a color filter, turning the Moon (or Sun) blue: more.

SUDDEN IONOSPHERIC DISTURBANCE: Yesterday at 1415 UT, a C2-class solar flare erupted from sunspot 958. C-class flares are generally considered weak, but solar flares are so powerful, even a "weak" one can directly affect our planet. Here's proof:

When the flare erupted, amateur radio astronomer Rudolf Slosiar of Bojnice, Slovakia, was monitoring a distant 20 kHz terrestrial radio transmitter. The flare caused the signal to surge; note the spike in the plot, above. How do flares do this? X-rays from solar flares knock electrons off molecules in Earth's upper atmosphere, boosting the density of electrons in the ionosphere. This, in turn, improves the propagation of very low frequency (VLF) radio waves around Earth. Such events are called "sudden ionospheric disturbances" or SIDs.

If you would like to observe SIDs yourself, visit the American Association of Variable Star Observer's website for instructions.

BACKWARD SHADOWS: "Is it the end of the world?" asks photographer Nick King of Harrow, UK. "I was in the garden at home when I saw this cloud silhouetted by the sun. It looked like a mushroom cloud to me!"

Photo details: Canon 300D, 18-35mm lens

In fact, it's just an ordinary cumulous cloud--a billowing tower of moist air rising to the heavens where the water will eventually fall back to the ground as rain.

The cloud may be ordinary, but the shadows it cast are quite interesting, says atmospheric optics expert Les Cowley. Note the dark shadows at the top of the cloud; while the sun is shining down, those shadows seem to be going up. He explains: "The cloud top is actually casting shadows downwards onto two thin haze layers below it. Perspective effects make the shadows appear larger and the sunbeams appear to radiate outwards."

Backward shadows? The end of the world? You see, it's all an illusion....

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 May 31, 2007 there were 863 potentially hazardous asteroids.
May 2007 Earth-asteroid encounters:
Miss Distance
1862 Apollo
May 8
72 LD
2.4 km
2007 JD
May 11
12 LD
100 m
2007 JZ2
May 14
7.0 LD
30 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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