[meteorite-list] Annual Influx Rate and Average Velocity
From: Chris Peterson <clp_at_meteoritecentral.com>
Date: Tue, 23 Aug 2011 15:51:30 -0600 Message-ID: <4E5420E2.4060606_at_alumni.caltech.edu> Simple mathematics requires that any particular meteoroid class will have "one average velocity". But the standard deviation is huge! It doesn't matter whether you are talking about dust, pebbles, boulders, or asteroids: the body will have an orbital velocity where it crosses Earth's orbit that depends on the eccentricity of the orbit (and there is a very wide range, from circular to slightly hyperbolic). The actual impact velocity is further determined by the inclination, whether the orbit is prograde or retrograde, and by Earth's axial rotation. So I don't think that there is much value to the idea of an "average" meteoroid velocity unless you break down your categories much finer. Chris ******************************* Chris L Peterson Cloudbait Observatory http://www.cloudbait.com On 8/23/2011 2:22 PM, Robert Beauford wrote: > I need a decent estimate of average annual meteorite influx rate (total mass at all scales per year) and I'm not sure who has done the best and most recent job. > Can anyone suggest a source? > Also, does anyone have any idea whether anyone has worked out a meaningful average speed (from real data) for inbound objects? > I suspect that everything from pebble size to large masses have one average velocity and that dust has a different average velocity. > Any insights would be greatly appreciated. > Thanks, > Robert Beauford Received on Tue 23 Aug 2011 05:51:30 PM PDT |
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