[meteorite-list] An Inexpensive Rooftop Fireball Patrol

From: Julien.Courtois_at_gr.admin.ch <Julien.Courtois_at_meteoritecentral.com>
Date: Thu Apr 22 09:52:12 2004
Message-ID: <EAB746AD969AA24C9EBBF84B28065B8825C5C9_at_ber-ex-05.ber.gr.admin.ch>

Hello list,

I cannot remember to have seen this article mentionned on this list:

<http://skyandtelescope.com/news/current/article_679_1.asp>

BTW, is Ed still on this list?

An Inexpensive Rooftop Fireball Patrol
By David L. Chandler

  
Edward Albin's fireball monitor keeps an eye out for bright falling stars in
the skies over Atlanta, Georgia. Meteors brighter than 1st magnitude are
recorded by the video camera mounted above the fisheye mirror. Courtesy
Edward Albin
 
   
July 29, 2002 | The whole thing cost just more than $200, it requires
virtually no maintenance except a once-a-month dusting, and it provides a
useful service that hasn't been widely available before. And it may just be
the start of something big: an all-sky, all-night fireball monitoring
program.
Edward Albin, an astronomer at the Fernbank Science Center in Atlanta, built
and set up the video system two months ago on the roof of his home just
outside Atlanta (to avoid the city's light pollution at the science center
itself). Having received many calls from the public over the years with
reports of apparent fireball sightings, he decided that it would be useful
to have a way to check back when such accounts come in. He could then both
confirm that it was indeed a fireball - potentially staving off some UFO
reports - and provide details of the meteor's time and heading. Similar
systems have been set up by Sandia National Laboratory.

Albin built the simple setup from a hemispherical, acrylic "corner mirror"
like the ones that help you avoid shopping-cart collisions in the
supermarket. He mounted the foot-wide (30-centimeter) mirror horizontally on
a cut-to-size piece of plywood, and secured it with a silicone adhesive.
Initially condensation occasionally formed on the mirror, but that problem
disappeared after Albin put a small electric heating pad inside the dome.

  
Edward Albin's fireball monitor would easily snare bright meteors such as
this Perseid captured by Russell Sipe. Notice the color changes in the
"tail." Courtesy Russell Sipe.
    
A simple metal-rod tripod supports the downward-pointing video camera above
the mirror, providing a full-sky fisheye view. The 12-volt, black-and-white
CCD camera, obtained from a surveillance video company, has a sensitivity of
0.0003 lux, allowing it to pick up stars to 1st magnitude, Albin says. The
camera is enclosed in a piece of PVC pipe with a cap for weather protection.
Once a month, he goes up on the roof to clean the apparatus, which mostly
means removing spider webs.

The images are captured on a standard VHS recorder in the house, connected
by standard coax to the setup on the roof's ridge line, using 8-hour tapes
(up to two per night in winter). At present, he checks the tapes only if
there is a fireball sighting.

An informal network of such simple and inexpensive devices could make it
possible not only to establish the time and direction of any fireballs
observed in the area, but potentially to triangulate the paths and get
detailed elevation and position data, Albin says. But even individual
monitors can provide useful information at relatively low cost. "It is
amazing how many fireballs and bolides have escaped capture on video, even
in our modern techno-gadget age," he says.
Received on Mon 12 Aug 2002 08:40:00 AM PDT