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ATMOSPHERIC OPTICS
EXHIBITION: The Boyden Gallery of St.Mary's
College in Maryland is planning a major exhibition of atmospheric
optics photos during the summer of 2010. Got images? The deadline
for submissions is Nov. 30, 2009. Atmospheric optics expert
Les Cowley has the full
story.
RETURNING SUNSPOT:
The most active sunspot of the year, sunspot
1029, has spent the past week transiting the far side of the
sun. It is still invisible from Earth, but the active region
is coming into range of cameras onboard NASA's STEREO-B probe.
The spacecraft beamed back this extreme ultraviolet image
just hours ago:
A farside eruption on Nov. 5th (movie)
suggests that the sunspot is still active. In late October,
the last time we saw it on the Earth-facing side of the sun,
sunspot 1029 unleashed more than 10 C-class
solar flares, single-handedly quadrupling the total number
of flares in all of 2009. The sun's rotation will turn the
active region back toward Earth about four days from now.
Until then, STEREO-B will keep us informed. Stay tuned.
BONUS: weekend
solar images: from
Pete Lawrence of Selsey, West Sussex, UK; from
Alan Friedman of Buffalo, New York; from
Jan Timmermans of Valkenswaard, The Netherlands
WEEKEND FIREBALLS:
On Saturday, Nov. 7th, just as the sun was
setting over San Francisco Bay, a brilliant meteor glided
across the sky and disappeared into the sunset. Witnesses
say it was "slow-moving," "white and green,"
and that it left behind "a trail of smoke and sparkles
of debris." The fireball was gone before most photographers
had a chance to raise their cameras, but several people managed
to capture the lingering trail of debris:
Gwen Wagy took this picture out the window of a car in Marina,
Califonia. "The twisting trail resembled a noctilucent
cloud," notes husband Chris.
Meteor expert Peter Jenniskens of NASA's Ames Research Center
believes the fireball was "a small asteroid that crashed
into our atmosphere. The remains [of the space rock] probably
landed in the Pacific Ocean."
Another possibility is that the fireball was a piece of periodic
Comet 2P/Encke. Every year around this time, Earth passes
through a stream of debris from the comet, and the encounter
causes meteors to shoot out of the constellation Taurus. "The
Taurid shower is definitely active," notes Bill Cooke
of NASA's Meteoroid Environment Office. "Our all-sky
cameras have been picking up a couple of Taurid fireballs
every night." At the time of the Bay Area fireball, the
constellation Taurus was rising in the east, so a Taurid identification
is not yet out of the question.
On the same night a few hours later, Brian Emfinger
of Ozark, Arkansas, photographed a definite Taurid: movie.
"I estimate its brightness at around magnitude -10 (almost
200 times brighter than Venus)." Sky watchers should
be alert for more fireballs in the nights ahead as Taurid
activity continues until at least Nov. 12th. The best time
to look is during the hours around midnight when the constellation
Taurus is high overhead: sky
map.
more images: from
Bryan Murahashi of Sunnyvale, California; from
Rick Baldridge of Campbell, California; from
Pepper De la Cruz of Half Moon Bay, California;
October
Northern Lights Gallery
[previous Octobers: 2008,
2007, 2006,
2004, 2003,
2002, 2001]
Explore
the Sunspot Cycle |
