[meteorite-list] Any Meteorites of Earth Origin?
From: Jeff Grossman <jgrossman_at_meteoritecentral.com>
Date: Thu Apr 22 09:47:10 2004 Message-ID: <5.1.0.14.2.20011111192121.03c82170_at_pop3.norton.antivirus> At 04:34 PM 11/11/2001, meteorites_at_space.com wrote: >On Sun, 11 November 2001, Jeff Grossman wrote: > > > > > Alan Rubin and I wrote a definition of "meteorite" for Meteorite! a while > > back that allowed for terrestrial meteorites. Our current thinking is > that > > the object would have to have left Earth by natural processes > > (impact-launching seems the only option, although this is highly > > improbable), either by achieving escape velocity, or by insertion into > > Earth orbit via some secondary change to its trajectory (we want to > > eliminate material on ballistic paths that take it immediately back to > > Earth, e.g., tektites). If such material later reaccretes to Earth or > > accretes to another body (like the Moon or an asteroid), we would define > > this as a terrestrial meteorite. > > > > Of course, we already have terrestrial meteorites in our collections if > the > > well-accepted theory of lunar formation is correct. But that's just > > semantics. There is no evidence for more recent events on Earth producing > > terrestrial meteorites. > > > > jeff > > >Tektites, the Australites in particular are "terrestrial meteorites." > >Steve Schoner. >AMS What makes you say that? Jeff Dr. Jeffrey N. Grossman phone: (703) 648-6184 US Geological Survey fax: (703) 648-6383 954 National Center Reston, VA 20192, USA Received on Sun 11 Nov 2001 07:26:47 PM PST |
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