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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: 476.9 km/sec
density: 2.7 protons/cm3
explanation | more data
Updated: Today at 2243 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Feb17
24-hr: A0
2245 UT Feb17
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 17 Feb 08
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 17 Feb 2008
Far side of the Sun:
This holographic image reveals no large sunspots on the far side of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 2
quiet
explanation | more data
Current Auroral Oval:

Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Updated:
What is the auroral oval?
Interplanetary Mag. Field
Btotal: 4.2 nT
Bz: 0.6 nT north
explanation | more data
Updated: Today at 2247 UT
Coronal Holes:
Earth is exiting a solar wind stream flowing from the indicated coronal hole. Credit: SOHO Extreme UV Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2008 Feb 17 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 Feb 17 2203 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
01 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
25 %
20 %
MINOR
05 %
01 %
SEVERE
01 %
01 %

What's up in Space
February 17, 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

SPY SATELLITE: Doomed spy satellite USA 193 is still orbiting Earth and making evening flybys of US towns and cities. Last night it passed over El Cajon, California, "fairly bright and right on time," reports Mike O'Leary who snapped this picture. The US Navy plans to hit USA 193 with an Aegis missile after space shuttle Atlantis returns to Earth (out of harm's way) on Feb. 20th. Stay tuned for updates. [flyby alerts] [comments] [more images: #1, #2]

TWO SPACESHIPS: The streak of light in this photo is about to split in two:

"The International Space Station (ISS) and space shuttle Atlantis flew over Nishapur, Iran, on Feb. 16th," says photographer Saeid Aghaei. "The docked spaceships appeared as a single streak of light through the branches of a Khayyam grape vine."

On Monday morning, Feb. 18, at 4:26 am EST, Atlantis will undock from the ISS, causing the streak to split. This is big news for many sky watchers across the United States who will be able to see Atlantis and the ISS on Monday evening as distinct points of light gliding in tandem across the twilight sky--an unforgettable sight. Flyby alerts are available to subscribers of Spaceweather PHONE.

more images: from Steve Newcomb of Oakland, MD; from Joseph Westerberg at the Joshua Tree National Park, California; from Kirk Benson of Yorba Linda, California; from Matt Ridley of Gaithersburg, Maryland; from Ralf Vandebergh of the Netherlands;

PARALLAX: Last week, Mila Zinkova photographed the sun through a thick San Francisco fog. Inspecting the photo, "I noticed that the sun's reflection in the pond appears at the tip-top of a street light--but the actual sun in the sky is much higher than the street light." What's going on? Scroll down for the answer.

Atmospheric optics expert Andrew Young explains: "The answer is parallax. The reflection in the water shows the view as seen from a 'reflected camera'--that is, a point that is the camera's reflection in the water, as far below the surface as the real camera is above it." From that point of view, the streetlight has moved up to partially cover the sun. "These perspective effects are always present in pictures of reflections in water -- but not often as obvious as in Mila's picture, which is a 'textbook example' of the effect."

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 February 17, 2008 there were 926 potentially hazardous asteroids.
Feb. 2008 Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Mag.
Size
2008 CT1
Feb. 5
0.3 LD
15
13 m
2007 DA
Feb. 12
9.8 LD
18
140 m
2008 CK70
Feb. 15
1.0 LD
16
40 m
4450 Pan
Feb. 19
15.9 LD
13
1.6 km
2002 TD66
Feb. 26
16.7 LD
15
440 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...
©2008, SpaceWeather.com -- This site is penned daily by Dr. Tony Phillips.
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