[meteorite-list] Error in AMSMETEORS fireball sketch

From: Matson, Robert <ROBERT.D.MATSON_at_meteoritecentral.com>
Date: Thu Apr 22 09:43:35 2004
Message-ID: <AF564D2B9D91D411B9FE00508BF1C8698E5589_at_US-Torrance.mail.saic.com>

On a seemingly nitpicky note, the sketch shown to the right of the map
has the sun in the wrong position:

<http://www.amsmeteors.org/fireball/fireball_log.html>

It shows it 34 degrees above due west. If the reconstruction of the
bolide trajectory from this Wyomissing, PA location is based on the
sun's location, then the compass coordinates need to be shifted.
The actual sun location at 6:18pm EDT was azimuth 277.6, elevation
22.6 degrees. I'm sure this is simply a case of an observer
overestimating the elevation angle of an object -- with amateurs
it happens without fail. Try it with anyone: tell them to point
where they think 45 degrees above the horizon is located. They'll
likely point about 30 degrees up.

The error may not seem like a big deal, but it makes a big
difference in the reconstruction of the actual trajectory. This
sketch makes it appear the bolide was headed almost east to
west, which it most definitely did not. Clearly a lot of weight
has been placed on this observation based on the east-west
orientation of the green rectangle on the map -- an orientation
which is off by at least 40 degrees, probably more.

--Rob
Received on Wed 25 Jul 2001 03:07:31 PM PDT