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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
SPACE WEATHER
Current conditions
Solar wind
speed: 474.6 km/sec
density: 2.5 protons/cm3
explanation | more data
Updated: Today at 2246 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Mar18
24-hr: A1
1440 UT Mar18
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 18 Mar 08
Small sunspot 986 is disappearing over the sun's western limb. Credit: SOHO/MDI
Sunspot number: 11
What is the sunspot number?
Updated 17 Mar 2008
Far side of the Sun:
This holographic image reveals no sunspots on the far side of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 4
unsettled
explanation | more data
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 3.9 nT
Bz: 1.3 nT north
explanation | more data
Updated: Today at 2247 UT
Coronal Holes:
There are no well-defined coronal holes on the Earth-facing side of the sun. Credit:SOHO Extreme UV Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2008 Mar 18 2203 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: 2008 Mar 18 2203 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
05 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
05 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
What's up in Space
March 18, 2008
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.   mySKY

LOOKING FOR SATURN? Tonight it's easy to find. Go outside after sunset, locate the Moon (you can't miss it), and note the golden star beside it. That "star" is Saturn. One quick slew takes your telescope from lunar craters to icy rings and back again--it's all good!

EXTRA: Science@NASA story: The Vanishing Rings of Saturn

LUNAR IMPACT: On March 13th, amateur astronomer George Varros of Mt. Airy, Maryland, was monitoring the dark limb of the Moon using his 8-inch Celestron telescope. With no warning, an explosion ensued:

The flash in this short movie is a meteoroid hitting the Moon with about as much energy as ~100 kg of TNT. "This gives new meaning to 'shoot the Moon'," says Varros. "The flash was also seen by three NASA telescopes in Alabama and Georgia."

Since 2005, careful monitoring by astronomers at NASA's Meteoroid Environment Office has shown that space rocks hit the Moon with surprising regularity and the resulting flashes are visible in ordinary backyard telescopes. Varros has recorded three impacts this year alone.

The best time to look is during a meteor shower, but sometimes a random meteoroid associated with no known shower plummets to the ground. Such was the case on March 13th. "It seems to have been a sporadic meteor," says Varros. "It struck at lunar coordinates 78oW, 23oS, not far from crater Darwin."

Readers, are you ready to join the hunt? Start here.

MOON FINGERS: "A couple of nights ago, the sky was clear in Northern Ireland apart from some long fingers of cirrus cloud," reports photographer John C McConnell. "I watched as they passed in front of the Moon and this fragmented halo appeared."


Photo details: Canon 400D, 18mm lens, 20 seconds

Moon halos, like better-known sun halos, are caused by ice crystals in high clouds. If the clouds are fragmented, so are the halos. "Later," continues McConnell, "the sky became uniformly hazy and indeed a full halo appeared."

The Moon is big and bright this week, which makes it a good time to watch for halos and their cousins, moondogs and pillars. "It always pays to keep an eye on the sky!"

more images: from Jeffrey Berkes of West Chester, PA; from Nicolai Wiegand of Germany, Schöningen; from D. Clark of Jonesville, VA; from Jesus Pelaez of Lodoso (Burgos) SPAIN;

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. [comment]
On March 18, 2008 there were 943 potentially hazardous asteroids.
March 2008 Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2008 DH5
Mar. 5
7.1 LD
18
60 m
2008 EZ7
Mar. 9
0.4 LD
18
18 m
2008 ED8
Mar. 10
1.4 LD
12
64 m
2008 EF32
Mar. 10
0.2 LD
18
6 m
2008 EM68
Mar. 10
0.6 LD
18
12 m
1620 Geographos
Mar. 17
49 LD
13
3 km
2003 FY6
Mar. 21
6.3 LD
15
145 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 Weather Prediction 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...
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