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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: 530.2 km/sec
density: 2.8 protons/cm3
explanation | more data
Updated: Today at 2246 UT
X-ray Solar Flares
6-hr max: A0
2245 UT Feb21
24-hr: A0
2245 UT Feb21
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 21 Feb 08
The sun is blank--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 21 Feb 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= 1 quiet
24-hr max: Kp= 3
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: 2.3 nT
Bz: 0.6 nT north
explanation | more data
Updated: Today at 2247 UT
Coronal Holes:
There are no coronal holes on the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
SPACE WEATHER
NOAA Forecasts
Updated at: 2008 Feb 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 Feb 21 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
10 %
10 %
MINOR
05 %
05 %
SEVERE
01 %
01 %

What's up in Space
February 21, 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-SAT HIT: Last night, the US Navy successfully hit spy satellite USA 193 with a missile over the Pacific Ocean: video. The strike occured at 10:26 p.m. EST on Feb. 20th. "Due to the relatively low altitude of the satellite at the time of the engagement, debris will begin to re-enter Earth's atmosphere immediately," says the US Dept. of Defense. "Nearly all of the debris will burn up on reentry within 24-48 hours." [comment]

SIGHTING: From the summit of Maui's Haleakala volcano, not far from the Navy ships that struck USA 193, Rob Ratkowski may have photographed fragments of the shattered satellite. Read his report.

TOTAL LUNAR ECLIPSE: Last night, the shadow of Earth fell across the full Moon producing a lovely red lunar eclipse. Mohammad Taher Pilevar sends this stunning photo comes from Hamedan, Iran:

Sky watchers from Persia to Hawaii witnessed the spectacle, which won't repeat itself for nearly three years. The next total eclipse of the Moon comes in Dec. 2010. Clouded out? Browse the gallery to see what you missed:

Lunar Eclipse Photo Gallery
[Interactive World Map of Eclipse Photos]

ACID IN THE SKIES: The UK, Netherlands, Germany and Scandinavia are experiencing a series of unusually bright and colorful sunsets. "It looks very mysterous," reports Michiel de Boer of the Netherlands. "The sky does not turn the usual twilight-blue. Instead, it remains yellow even after sunset and only slowly fades." He offers this snapshot taken Feb. 18th:

"I took the picture using my Canon 350D," he says. "Here's another showing the sky 50 minutes after sunset."

What is going on? Atmospheric optics expert Les Cowley explains: "Volcanic ash high in the stratosphere can give us similar twilights but is not the cause this time. A more likely explanation is Type1 polar stratospheric clouds (PSCs). These clouds are located 15-25km (9-16 miles) above the earth and they can be illuminated by the sun even after 'sunset.' The exceptionally low temperatures needed to form Type 1 PSCs have existed over Europe for the last day or so."

"Type1 PSCs are composed of nitric acid compounds and are less colourful and bright than the better known Type2 or nacreous clouds made of ice crystals. Sometimes we see nacreous clouds embedded in their less colourful acidic neighbors."

More images: from Rob Stewart at Mull loch na keal, Western Scotland; from Jacob Kuiper of De Bilt, The Netherlands; from Martin Mc kenna of Maghera, Co. Derry, N. Ireland; from Eva Seidenfaden of Trier, Germany; from Graeme Whipps of Aberdeenshire, Scotland, UK; from Jeremy Housman of Ramsgate, Kent, United Kingdom; from Vincent Phillips of Hale Village (Near Liverpool) England; from Reinhard Nitze of Barsinghausen, North Germany;

React: Comment on this story

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 21, 2008 there were 927 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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