[meteorite-list] Modeling the Park Forest bolide

From: Matson, Robert <ROBERT.D.MATSON_at_meteoritecentral.com>
Date: Thu Apr 22 10:21:04 2004
Message-ID: <AF564D2B9D91D411B9FE00508BF1C86901B4EB7B_at_US-Torrance.mail.saic.com>

Hi Ron,

> Thanks for the plot!

No problem -- it was fun to see how much the apparent trajectory
moves around depending on your exact location.

> Bob Verish pointed out to me that in another eyewitness case
> (not Park Forest), a fireball was observed to be travelling
> 'up'. This can happen with the right viewing perspective with
> a low-angle flight path, even though the fireball is really
> falling down.

Absolutely.

> Again, the DOD data indicates the strewnfield is larger then
> originally thought, particularly along the true flight path.

I concur. The next step in the exercise for me is to plug in
some Cd values for a range of meteorite sizes (e.g. 5 grams,
50 grams, 500 grams, 5 kilos) and see where the error ellipses
end up when I fly the fragments into the ground. I'll also
have to vary the altitude associated with the 20 km/sec velocity
reported by DoD since it wasn't provided in their report. I'll
start with 100 km, 75 km, 50 km and 25 km and see how much that
changes the shape and location of the ground footprints.

A couple ancillary products will come from such an analysis:
the impact velocity vs. mass, and the time it takes to fall
from, say, 100-km altitude to the ground.

--Rob
Received on Mon 14 Jul 2003 01:41:42 PM PDT