[meteorite-list] Speed that meteors enter dark flight?

From: Chris Peterson <clp_at_meteoritecentral.com>
Date: Wed, 07 Mar 2012 11:58:54 -0700
Message-ID: <4F57AFEE.5040307_at_alumni.caltech.edu>

It depends on the mass of the body. But realistically, under "typical"
conditions that might lead to meteorite production, I think it's safe to
say that this happens almost instantly.

For example, a 100 kg stone that survives to 20 km height will be
experiencing a deceleration of ~1500 m/s^2. A 10 kg stone will
experience ~4000 m/s^2. Of course, no stone is likely to survive the
forces that would result without breaking up. You need to play all sorts
of games with different parameters for mass, speed, and height to find
survivable scenarios. They all produce a very short period of dark
flight before terminal velocity.

This is why the retardation point is typically overhead any strewn
field, and you don't usually have meteorites significantly down field
from the retardation point. In fact, wind during dark flight may move
meteorites farther than their last bit of momentum did- and that can be
in any direction.

Chris

*******************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

On 3/7/2012 11:45 AM, Mike Hankey wrote:
> the follow up to this question/answer I still wonder about is:
>
> after dark flight begins, how many seconds will it take to completely
> decelerate so that all forward momentum is lost after dark flight
> starts.
>
> for example: if the meteor goes dark at 4km/s how many seconds before
> it will be at 0km/s and/or what does that deceleration curve look
> like?
>
Received on Wed 07 Mar 2012 01:58:54 PM PST