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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 325.8 km/sec
density: 1.1 protons/cm3
explanation | more data
Updated: Today at 2345 UT
X-ray Solar Flares
6-hr max: C1
1729 UT Feb25
24-hr: C1
0544 UT Feb25
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 25 Feb 11
New sunspot 1163 produced a spectacular M3-class solar flare on Feb. 24th. Credit: SDO/HMI
Sunspot number: 23
What is the sunspot number?
Updated 24 Feb 2011

Spotless Days
Current Stretch: 0 days
2011 total: 1 day (2%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 820 days
Typical Solar Min: 486 days

Updated 24 Feb 2011

The Radio Sun
10.7 cm flux: 89 sfu
explanation | more data
Updated 24 Feb 2011

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 1
explanation | more data
Interplanetary Mag. Field
Btotal: 3.7 nT
Bz: 2.5 nT north
explanation | more data
Updated: Today at 2346 UT
Coronal Holes: 25 Feb 11
A large coronal hole is emerging over the sun's eastern limb. Credit: SDO/AIA.
NOAA Forecasts
Updated at: 2011 Feb 25 2200 UTC
0-24 hr
24-48 hr
50 %
50 %
05 %
05 %
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 25 2200 UTC
0-24 hr
24-48 hr
10 %
10 %
01 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
15 %
01 %
01 %
01 %
01 %
Friday, Feb. 25, 2011
What's up in space

Metallic photos of the sun by renowned photographer Greg Piepol bring together the best of art and science. Buy one or a whole set. They make a stellar gift.

Metallic pictures of the Sun

LAST FLIGHT OF DISCOVERY: The final voyage of space shuttle Discovery is underway. The orbiter lifted off at 4:53 p.m. EST Thursday from NASA’s Kennedy Space Center on a 12-day mission to deliver Robonaut 2 and supplies to the International Space Station. Discovery is currently chasing the ISS around Earth, and it may be possible to see them both as they converge in the night sky. Check the Simple Satellite Tracker for flyby times.

launch images: from Pete Lardizabal at the Canaveral National Seashore Park, FL; from Mike Theiss at the Kennedy Space Center

EARTH DODGES A BULLET: New sunspot 1163 doesn't look very impressive, but the M3-class flare it unleashed yesterday was absolutely spectacular. Click to play a movie recorded by NASA's Solar Dynamics Observatory:

When the eruption occurred, sunspot 1163 was behind the sun's eastern limb. Nevertheless, enough ultraviolet radiation spilled over to create waves of ionization in Earth's upper atmosphere. Low-frequency radio signals, which bounce off of ionized air, were strongly disturbed, as shown in this plot from a VLF monitoring station in Slovakia. Otherwise, Earth was little affected. Plasma clouds produced by the blast did not come our way.

Sunspot 1163 will continue turning toward Earth in the days ahead, setting the stage for more potent geo-effects if the eruptions continue. Stay tuned.

SOLAR SAIL FLARE: Last night (Feb. 23), NanoSail-D sailed over Seinäjoki, Finland, and when it did, the spacecraft's reflective fabric caught a sunbeam and flared. "I've never seen anything like it," says Juha Peräsaari who recorded the event using a Canon 400D digital camera:

Photo details: Canon EOS 400D, 20mm lens, f2.8, ISO100, 10s exposure. [more]

"NanoSail-D 'flashed' just as it passed the star Procyon," he says. "For a moment, the sail was the brighter of the two." This means NanoSail-D can flare at least to magnitude +0.3 (the brightness of Procyon), or almost twice as bright as a first magnitude star.

Even brighter flares could be in the offing. The orbit of NanoSail-D is decaying as it skims the top of Earth's atmosphere. Sunglints from the descending sail could intensify to Venus-brightness and beyond. Anyone who photographs such an event could win $500.

NanoSail-D Photo Gallery
[NASA: Solar Sail Stunner] [Photo Contest]

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 25, 2011 there were 1201 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2011 DS
Feb 18
2 LD
18 m
2011 CL50
Feb 19
6.2 LD
13 m
2003 YG118
Feb 20
67.7 LD
1.8 km
2011 DQ
Feb 26
9.7 LD
24 m
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
2002 JB9
Jun 11
71.5 LD
3.2 km
2001 VH75
Jun 12
42.2 LD
1.1 km
2004 LO2
Jun 15
9.9 LD
48 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
Conquest Graphics
  for out-of-this-world printing and graphics
Science Central
  more links...
©2010 All rights reserved. This site is penned daily by Dr. Tony Phillips.
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