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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 351.0 km/sec
density: 1.3 protons/cm3
explanation | more data
Updated: Today at 2344 UT
X-ray Solar Flares
6-hr max: B7
2300 UT Feb09
24-hr: M1
0131 UT Feb09
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 09 Feb 11
Sunspot 1153 is growing more active, now crackling with C- and M-class solar flares. Credit: SDO/HMI
Sunspot number: 71
What is the sunspot number?
Updated 08 Feb 2011

Spotless Days
Current Stretch: 0 days
2011 total: 1 day (3%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 820 days
Typical Solar Min: 486 days

Updated 08 Feb 2011

The Radio Sun
10.7 cm flux: 90 sfu
explanation | more data
Updated 08 Feb 2011

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: 2.2 nT
Bz: 1.3 nT north
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 09 Feb 11
Solar wind flowing from the indicated coronal holes should reach Earth on Feb. 13th or 14th. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Feb 09 2200 UTC
0-24 hr
24-48 hr
20 %
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: 2011 Feb 09 2200 UTC
0-24 hr
24-48 hr
20 %
20 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
20 %
20 %
01 %
01 %
01 %
01 %
Wednesday, Feb. 9, 2011
What's up in space

Turn your cell phone into a field-tested satellite tracker. Works for Android and iPhone.

Satellite flybys

CLOSE ENCOUNTER WITH A VW-BUG: Newly-discovered asteroid 2011 CA7 is flying past Earth today only 63,000 miles away, or 1/4th the distance to the Moon. At closest approach around 1930 UT on Feb. 9th, the VW-Bug-sized space rock will zip through the constellation Orion glowing like a 17th magnitude star. [ephemeris] [3D orbit]

SOLAR ACTIVITY HEATS UP: Formerly quiet sunspot 1153 is suddenly crackling with C- and M-class solar flares. NASA Solar Dynamics Observatory recorded this eruption during the waning hours of Feb. 8th:

Movie formats: 1.8 MB iPad, 0.4 MB iPhone, 2 MB mpeg. See also the big still image.

Because sunspot 1153 is rounding the sun's western horizon, these eruptions are not Earth-directed. They are, however, Venus-directed. The second planet from the sun could receive glancing blows from solar plasma clouds in the days ahead. Readers with solar telescopes are encouraged to monitor the action.

HUBBLE FLARE: The Hubble Space Telescope (HST) is famous for many reasons, but visibility isn't one of them. On most nights, the great observatory registers a modest +3 on the magnitude scale, making a disappointingly faint streak as it moves among the stars. But every now and then, Hubble flares:

"I didn't know Hubble could do this," says M. Raşid Tuğral of Antalya, Turkey, who took the picture on Feb. 7th. "The HST suddenly flared to magnitude -2, almost as bright as the planet Jupiter." This is the kind of streak you could see even from brightly-lit cities; in the remote Turkish countryside, "it was dazzling."

Although not widely publicized, Hubble flares have been observed for years by members of the satellite-watching community. The luminous outbursts are caused by sunlight glinting from one of the spacecraft's flat surfaces--possibly the telescope's aperture door or its "aft skirt." Predicting Hubble flares is tricky because they depend sensitively on the telescope's observing schedule. Slewing from one galaxy to another, stopping for calibration, detouring to a newly-reported supernova: any of these actions could produce--or forestall--an absolute shadow-caster.

The only way to see a Hubble flare is to take a chance on looking. Let your cell phone be your guide.

February 2011 Aurora Photo Gallery
[previous Februaries: 2010, 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 9, 2011 there were 1196 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2011 BE24
Feb 3
9.3 LD
35 m
2011 CQ1
Feb 4
0.03 LD
2 m
2011 CF22
Feb 6
0.1 LD
3 m
2011 CA7
Feb 9
0.3 LD
4 m
2011 CZ3
Feb 10
2.5 LD
24 m
2003 YG118
Feb 20
67.7 LD
1.8 km
2000 PN9
Mar 10
45.5 LD
2.6 km
2002 DB4
Apr 15
62.5 LD
2.2 km
2008 UC202
Apr 27
8.9 LD
10 m
2009 UK20
May 2
8.6 LD
23 m
2008 FU6
May 5
75.5 LD
1.2 km
2003 YT1
May 5
65.3 LD
2.5 km
2002 JC
Jun 1
57.5 LD
1.6 km
2009 BD
Jun 2
0.9 LD
9 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 web 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 Dynamics Observatory
  Researchers call it a "Hubble for the sun." SDO is the most advanced solar observatory ever.
  3D views of the sun from NASA's Solar and Terrestrial Relations Observatory
Solar and Heliospheric Observatory
  Realtime and archival images of the Sun from SOHO.
Daily Sunspot Summaries
  from the NOAA Space Environment Center
  the underlying science of space weather
Science Central
  more links...
©2010 All rights reserved. This site is penned daily by Dr. Tony Phillips.
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