[meteorite-list] Meteorites on the moon
From: E.P. Grondine <epgrondine_at_meteoritecentral.com>
Date: Fri Sep 1 05:41:12 2006 Message-ID: <20060901094109.35979.qmail_at_web36907.mail.mud.yahoo.com> Hi Sterling, Rob, List - There is no combined model of asteroid and comet flux which accounts for the observed craters on all bodies in our solar system. The mechanics of the Earth-Moon system have never really been worked out. We really don't know if the Moon gets hit more often than the Earth ot less. Shoemaker, who did a lot of the early Apollo era work, later renounced a lot of it. By the way, no matter what you hear on TV, the impact of a comet killed the dinosaurs, not the impact of an asteroid. thoughts at 4 in the morning, godd hunting, Ed --- "Sterling K. Webb" <sterling_k_webb_at_sbcglobal.net> wrote: > Hi, Rob, List, > > > The ratio of the areas of Earth:Moon is roughly > 16:1, but > the deflection caused by Earth's stronger > gravitational reach > makes the ratio of impacts about 18:1. > The lunar impact rate is a more accurate measure > of the > meteroid flux in the vicinity of the Earth's orbit > than the Earth's > impact rate is, for that reason. > Even lunar gravity has a "focusing" effect in > attracting > meteroids. The actual "space" flux of meteroids is > calculated > to be about 85% to 86% of the rate implied by the > impact rate > on the Earth. > It's much harder to figure out an accurate rate > of impacts on > the Earth, though. As a result, we have no firm > figure to multiply > by 0.85. > > > Sterling K. Webb > -------------------------------------------------------------------------------- > > ----- Original Message ----- > From: "Rob McCafferty" <rob_mccafferty_at_yahoo.com> > To: <meteorite-list_at_meteoritecentral.com> > Sent: Friday, September 01, 2006 3:01 AM > Subject: Re: [meteorite-list] Meteorites on the moon > > > > ...lunar impacts are rarer than Earth ones due to > the > > weak gravity of the moon and not just it's smaller > > cross-section. > > > > Rob McC > > > ______________________________________________ > Meteorite-list mailing list > Meteorite-list_at_meteoritecentral.com > http://six.pairlist.net/mailman/listinfo/meteorite-list > __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com Received on Fri 01 Sep 2006 05:41:09 AM PDT |
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