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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: 337.8 km/sec
density: 2.6 protons/cm3
explanation | more data
Updated: Today at 2245 UT
X-ray Solar Flares
6-hr max: A1
2020 UT May18
24-hr: A1
2020 UT May18
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 17 May 08
Three new sunspots have emerged. These are small, old-Cycle 23 spots that pose no threat for solar flares. Credit: SOHO/MDI
Sunspot number: 23
What is the sunspot number?
Updated 16 May 2008
Far side of the Sun:
This holographic image reveals no sunspots on the farside of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 2
quiet
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: 5.3 nT
Bz: 3.3 nT south
explanation | more data
Updated: Today at 2245 UT
Coronal Holes:
There are no large coronal holes on the Earth-facing side of the Sun. Credit: SOHO Extreme UV Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2008 May 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 May 18 2203 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
20 %
25 %
MINOR
10 %
15 %
SEVERE
01 %
09 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
25 %
45 %
MINOR
15 %
25 %
SEVERE
01 %
10 %
What's up in Space
May 18, 2008
FLYBY ALERT! Space shuttle Discovery launches on May 31st. Get your flyby alerts from Space Weather PHONE  

TWIST AND SHOOT: Last week, over a period of two days (May 9th and 10th), NASA's Stereo-B spacecraft observed a troupe of magnetic filaments dancing along on the limb of the sun. For reasons that will become clear when you watch the performance, mission scientists have entitled the movie Twist and Shoot: 4.4 MB Quicktime, 8.1 MB mpeg.

ISS MARATHON: The 2008 "ISS Marathon" gets underway this week when the International Space Station spends three days (May 21-23) in almost-constant sunlight. Sky watchers in Europe and North America can see the bright spaceship gliding overhead two to four times each night. Please try our new and improved Simple Satellite Tracker to find out when to look.

The station is not only bright and easy to see with the naked eye, but also it makes a fine target for backyard telescopes:


Click to the view the 0.9 MB movie

"I took these pictures during the early morning hours of May 12th using a 5-inch refracting telescope." says amateur astronomer Dirk Ewers of Hofgeismar, Germany. For five minutes, he tracked the ISS across the sky and his movie of the entire 75o transit is a must see.

3D BONUS: Grab your 3D glasses. Spaceweather reader Sylvain Weiller of France has combined two frames of Dirk Ewer's movie to create a stereo view of the space station. If you don't have 3D glasses, try the cross-eyed version instead.

HALE'S LAW: On the sun this weekend, "four new active regions have appeared for us to look at in awe and wonderment," reports Stephen Ames of Hodgenville, Kentucky, who sends this sketch of the view through his Coronado PST. Each "active region" is a small sunspot or proto-sunspot struggling to coelesce.

Because these regions straddle the sun's equator, they nicely illustrate a basic law of sunspots: Hale's Law states that sunspots on opposite sides of the sun's equator have opposite magnetic polarity. Consider this magnetic map made by the Solar and Heliospheric Observatory (SOHO) on May 17th:


White represents N magnetic polarity; black represents S.

Sunspots are essentially magnetic, and each spot has its own "personal" north and south magnetic pole. Above the sun's equator, the poles are arranged S-N; below the sun's equator, they are reversed, N-S. That's Hale's Law, named after George Ellery Hale, who studied the magnetism of sunspots in the early 20th century.

more images: from Matthias Juergens of Gnevsdorf, Germany; from Pavol Rapavy of Rimavska Sobota, Slovakia; from Michael Borman of Evansville, Indiana; from Peter Paice of Belfast, Northern Ireland;


April 2008 Aurora Gallery
[Aurora Alerts] [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. [comment]
On May 18, 2008 there were 953 potentially hazardous asteroids.
May 2008 Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2008 HG
May 5
17 LD
18
90 m
2008 DE
May 9
17 LD
16
550 m
2008 HD2
May 9
6.5 LD
19
40 m
2008 JL24
May 10
0.4 LD
18
5 m
2008 HR3
May 11
3.1 LD
17
50 m
2008 HW1
May 14
72 LD
17
1.4 km
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...
©2008, SpaceWeather.com -- This site is penned daily by Dr. Tony Phillips.
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