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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: 568.9 km/sec
density: 0.5 protons/cm3
explanation | more data
Updated: Today at 2245 UT
X-ray Solar Flares
6-hr max: A0
1900 UT May21
24-hr: A0
1900 UT May21
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 19 May 08
These small sunspots pose no threat for solar flares. Credit: SOHO/MDI
Sunspot number: 23
What is the sunspot number?
Updated 20 May 2008
Far side of the Sun:
This holographic image reveals one possible, small high-latitude sunspot on the far side of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 1 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: 4.1 nT
Bz: 1.5 nT south
explanation | more data
Updated: Today at 2245 UT
Coronal Holes:
Earth is inside a solar wind stream flowing from the indicated coronal hole. Credit: SOHO Extreme UV Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2008 May 21 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 21 2203 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
25 %
25 %
MINOR
10 %
10 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
40 %
40 %
MINOR
20 %
20 %
SEVERE
10 %
10 %
What's up in Space
May 21, 2008
FLYBY ALERT! Space shuttle Discovery launches on May 31st. Get your flyby alerts from Space Weather PHONE  

100 EXPLOSIONS ON THE MOON: NASA astronomers have been watching the Moon to see how often meteoroids crash into the lunar surface and they've just video-recorded their 100th explosion. This bountiful data-set allows researchers to start drawing conclusions about when, where, and how hard the Moon gets hit. Get the full story and a video from Science@NASA.

ISS MARATHON: The 2008 "ISS Marathon" is underway . For the next three days, the International Space Station will be in almost constant sunlight. This means sky watchers in Europe and North America can see the spaceship gliding overhead as many as four times each night. When should you look? Click here.

The ISS is not only a beautiful naked-eye object, but also it makes a fine target for backyard telescopes:

This is the view through a 10-inch Newtonian. Ralf Vandebergh took the picture on May 14th when the ISS appeared over his home in the Netherlands. As the bright spacecraft glided slowly overhead, "I tracked the ISS by hand using the telescope's 6x30 finderscope," he explains.

On May 31st, space shuttle Discovery will launch and later rendevous with the ISS. Discovery's mission is construction: the crew will deliver and install a huge (37 feet x 14 feet) Japanese laboratory with its own robotic arm. The new Kibo Pressurized Module will be attached to the point marked "JLP" in Vandebergh's photo, making the ISS even bigger and brighter than it is now. Something to look forward to....

more images: from Sabahattin Bilsel of Erenkoy, Istanbul, Turkey; from Ugur İkizler of Mudanya, Bursa, Turkey; from P. Nikolakakos of Sparta, Greece; from Giuseppe Pappa of Mascalucia, Sicily, Italy; from J. Stone of Auburn, Alabama;

Space Station Flyby Times

PARHELIC CIRCLE: While most ice haloes we see go around the sun, there is one that goes right through it: the parhelic circle. "For a few minutes on the afternoon of May 19th, cloud conditions were right to form both a 22° halo around the sun and a perfectly-defined parhelic circle," reports Alan Dyer who took the photo, below, from Alberta Canada. "This produced a sky filled with two intersecting halos--a rare sight."

"Now is a good time of year to see parhelic circles because they appear high in the sky," notes atmospheric optics expert Les Cowley. "The altitude of the circle always matches the altitude of the sun, hugging the horizon in winter and rising high overhead in summer. The higher the sun, the smaller is the circle, and it can even shrink smaller than the 22o halo seen crossing it in Dyer's photo. Almost all types of ice crystal carve the parhelic circle, it looks very simple but it is made in more ways than any other halo."

Parhelic circles are pale white like the icy clouds that make them. "Look carefully to distinguish it from white clouds," urges Cowley. "With luck you will see a complete circle."

more images: from Aymen Ibrahem at the Bibliotheca Alexandrina in Alexandria, Egypt; from Enzo De Bernardini of Martínez, Buenos Aires, Argentina; from Stanislaw Rokita of Torun, Poland; from Marco Candotti of Palmanova, Friuli, Italy;


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 21, 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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