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AURORA WATCH:
Arctic sky watchers should be alert for Northern Lights tonight.
A solar wind stream is heading for Earth, and NOAA forecasters estimate
a 30% chance of high-latitude geomagnetic activity when it arrives
sometime during the next 24 hours: gallery.
THE GREEN COMET COMETH:
From remote Portal, Arizona, astrophotographer
Jack Newton reports: "Comet Lulin has brightened considerably
and is now an easy naked eye object in dark, country skies."
He photographed it using a Meade 14" HyperStar and sends this
16-minute exposure:
Comet Lulin's vivid green atmosphere is about three times as wide
as the planet Jupiter, and its dusty tail stretches more than 1.5
million km into space. The comet is so big that "it no longer
completely fits in my telescope's field of view," says Newton.
On Feb. 24th, Comet Lulin will swing past Earth only 38 million
miles away. Got clouds? No problem. The Coca-Cola
Space Science Center in Columbus, Georgia, plans to webcast
the encounter. "We're going to transmit the view through our
observatory's 16-inch Schmidt-Cassegrain telescope," says astronomy
professor Rosa Williams of Columbus State University. "The
webcast begins at 11:30 EST on Monday, Feb. 23rd and will continue
until 5 a.m. EST on Tuesday the 24th." Tune
in!
UPDATED: Comet
Lulin Photo Gallery
[Comet
Hunter Telescope] [Sky maps: Feb.
18, 19,
20]
SATELLITE DEBRIS UPDATE:
US Strategic Command has identified a new
batch of fragments from the Feb. 10th satellite
collision over northern Siberia. "The count is now at 49
pieces for Iridium 33 and 85 for Kosmos 2251," says Canadian
satellite tracker Daniel Deak, who has prepared some 3D maps of
the debris for readers of spaceweather.com. Click on the image to
view a snapshot of Iridium fragments on Feb 20th:
A similar map
traces the Kosmos debris.
Observations: Both satellites are now smeared all the way around
Earth; the original orbits are completely populated with fragments.
Furthermore, for reasons not fully understood, Kosmos is more widely
scattered than Iridium.
"The Kosmos debris ranges in altitude from 260 to 1450 km,
so some of the pieces now reach lower than the 350-km orbit of the
ISS," points out Deak. "For the Iridium debris, the fragments
are confined to orbits between 687 and 1127 km."
This doesn't mean the ISS is in immediate peril. Most of the Kosmos
scatter occurs over Antarctic latitudes. For comparison, the ISS
stays within 51.6 degrees of Earth's equator, so the dangers are
slight. The situation could change, however, as more fragments are
identified and their spread increases. Stay tuned for updates.
A complete set of debris maps: #1,
#2, #3,
#4, #5
February
2009 Aurora Gallery
[Previous Februaries: 2008,
2007,
2006,
2004,
2003,
2002]
Explore
the Sunspot Cycle
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