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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 365.5 km/sec
density: 2.3 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: A6
1845 UT Feb21
24-hr: B1
0155 UT Feb21
explanation | more data
Updated: Today at: 2340 UT
Daily Sun: 21 Feb. 10
Sunspot 1049 is slowly growing but it does not yet pose a threat for strong solar flares. Image credit: SOHO/MDI
Sunspot number: 19
What is the sunspot number?
Updated 20 Feb 2010

Spotless Days
Current Stretch: 0 days
2010 total: 2 days (4%)
2009 total: 260 days (71%)
Since 2004: 772 days
Typical Solar Min: 485 days
explanation | more info
Updated 20 Feb 2010

The Radio Sun
10.7 cm flux: 84 sfu
explanation | more data
Updated 20 Feb 2010

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 1
explanation | more data
Interplanetary Mag. Field
Btotal: 6.8 nT
Bz: 3.4 nT north
explanation | more data
Updated: Today at 2345 UT
Coronal Holes:
There are no large coronal holes on the Earth-facing side of the sun. Credit: SOHO Extreme UV Telescope
NOAA Forecasts
Updated at: 2010 Feb 21 2201 UTC
0-24 hr
24-48 hr
01 %
01 %
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: 2010 Feb 21 2201 UTC
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
05 %
05 %
01 %
01 %
01 %
01 %
What's up in Space
February 21, 2010

NEW AND IMPROVED: Turn your iPhone or iPod into a field-tested global satellite tracker. The Satellite Flybys app now works in all countries.


3D SUN FOR THE iPHONE: Imagine holding the entire sun in the palm of your hand. Now you can. A new iPhone app developed by NASA-supported programmers delivers a live global view of the sun directly to your cell phone: full story.

SHUTTLE SIGHTINGS: On Friday night, about three and a half hours after Endeavour undocked from the International Space Station, the shuttle performed a routine waste water dump. Two hundreds miles below on Earth, Ralf Vandebergh was standing in his backyard in the Netherlands pointing his camera at the sky. The picture he took was anything but routine:

"When I inspected the images," says Vandebergh, "I noted a misty cloud moving together with the two spacecraft. I quickly realized, it must be the Waste and Condensate Water dump performed by George Zamka and Terry Virts shortly after undocking."

Onboard the shuttle, astronauts likened the view out their window to a beautiful winter snowfall. The snowflakes in this case contained a fair measure of crystallized urine. It's got to go somewhere!

Endeavour is scheduled to land at the Kennedy Space Center on Sunday night, Feb. 21st, at 10:16 pm EST. However, unfavorable weather in Florida and at the backup landing site in California could keep the shuttle in orbit an extra day. This would give sky watchers one more chance to see the ISS and Endeavour together. Check the Simple Satellite Tracker to see if you are favored with an apparition.

more images: from Olivier Staiger of V├ętroz, Switzerland; from Marco Langbroek of Leiden, the Netherlands; from John C McConnell of Maghaberry, Northern Ireland; from Richard P. Nugent of Framingham, Massachusetts;

MAGNIFICENT MAGNETISM: NASA spacecraft and amateur astronomers alike are monitoring a staggeringly-long filament of magnetism on the sun. It is snaking more than a million kilometers around the sun's southeastern hemisphere. Click on the image to launch a 48-hour movie recorded by the Solar and Helioospheric Observatory (SOHO):

As the movie shows, this magnificent magnetic structure has remained mostly stable for at least two days. However, filaments like this one have been known to collapse, and when they hit the surface of the sun--bang!--a tremendous explosion results. Such blasts are known as "Hyder flares," and they can rival the strongest flares produced by sunspots. Solar physicists have not yet learned to predict Hyder flares, so we cannot estimate the odds of one now.

Readers with solar telescopes are encouraged to monitor developments.

more images: from C. Swiger and J. Stetson of South Portland, Maine; from Mark Townley of Brierley Hill, West Mids, UK; from Cai-Uso Wohler of Bispingen, Germany; from Alan Friedman of downtown Buffalo, NY; from Michael Wilk of Augsburg, Germany

February Northern Lights Gallery
[previous Februarys: 2009, 2008, 2007, 2006, 2004, 2003, 2002]

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.
On February 21, 2010 there were 1100 potentially hazardous asteroids.
Feb. 2010 Earth-asteroid encounters:
Miss Distance
2009 UN3
Feb. 9
14.3 LD
1.2 km
2010 CK19
Feb. 17
0.9 LD
11 m
2001 FD58
Feb. 19
58.5 LD
0.9 km
2010 CJ18
Feb. 19
3.3 LD
20 m
2002 EZ11
Feb. 24
77.5 LD
1.0 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 space weather bureau
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.
  3D views of the sun from NASA's Solar and Terrestrial Relations Observatory
Daily Sunspot Summaries
  from the NOAA Space Environment Center
Current Solar Images
  from the National Solar Data Analysis Center
Science Central
  more links...
©2008, -- This site is penned daily by Dr. Tony Phillips.













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