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FOSSIL SUNSPOT:
A sunspot is emerging
near the sun's eastern limb. The spot's low latitude and magnetic
polarity identify it as a fossil from old Solar Cycle 23. This breaks
a string of 23 consecutive spotless days beginning on Jan. 20th.
Readers, if you have a solar
telescope, take a look.
COLLIDING SATELLITES:
Experts are calling it an "unprecedented
event." Two satellites have collided in Earth orbit. Iridium
33 crashed into Kosmos
2251 on Tuesday, Feb. 10th, approximately 800 km over northern
Siberia. Click on the image to launch a 2.3 MB animation of the
collision:
Still images are also available: #1,
#2
Both satellites were completely destroyed. The expanding cloud
of debris contains more than 500 fragments, substantially increasing
the debris population at altitudes near 800 km. According to NASA,
the International Space Station orbiting 350 km above Earth is in
no immediate danger from the much higher-altitude debris.
The US Air Force Space Surveillance Radar in Texas reportedly detected
echoes from the debris cloud when it passed over the facility on
Feb. 11th. Spaceweather.com is streaming live
audio from the radar, and it might be possible to hear
echoes the next time debris passes overhead. Try listening on Thursday,
Feb. 12th, between 10:56 pm and 11:07 pm CST (0456 - 0507
UT on Feb. 13th). That's when Iridium 33 would have passed over
the radar intact had the satellite not been shattered.
UPDATE: Rumors are circulating that the debris
is radioactive. Not true. These satellites were not nuclear powered.
VIRTUAL REALITY MOON
HALO: "Two nights ago, my sister-in-law
Katy phoned me at 1 o'clock in the morning to say that there was
'a big crazy circle around the Moon,'" reports Laurent Laveder
of Quimper, France. "I went outside to look and she was right:
the sky was hazy, the Moon was very high and circled by a bright
22° ice
halo."
Click on the image to experience the halo as if you were there
yourself:
Virtual
Reality Moon Halo
Laveder explains how he created the VR halo: "I
took many pictures with my Canon
30D and a fisheye lens. Then I stitched the images together
into a 360° panoramic view, which we are able to spin around using
Quicktime
VR."
If it's cold where you live, be alert for more halos
tonight. The Moon is bright and northern skies are icy--perfect
conditions for the real thing.
Comet
Lulin Photo Gallery
[Comet
Hunter Telescope] [NASA's
story] [ephemeris]
February
2009 Aurora Gallery
[Previous Februaries: 2008,
2007, 2006,
2004, 2003,
2002]
Explore
the Sunspot Cycle
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