[meteorite-list] Meteorites on the moon
From: Mr EMan <mstreman53_at_meteoritecentral.com>
Date: Fri Sep 1 01:56:08 2006 Message-ID: <20060901055132.65605.qmail_at_web51003.mail.yahoo.com> Actually, "physics-ly" speaking, Earth holds far more meteorites than the moon does. Be it remembered, that without an atmosphere to slow them, the bulk of meteoroids arrive at full cosmic speeds and are most certainly vaporized by the collision. I haven't done the math but under an extreme glancing blow where the meteoroid is playing catch up, there might be a successive slowing of splashed fragments and some meteorite material may exist on the surface from time to time. Meteorites that may "defy" physics in this manner are going to be pulverized into the regolith over time by the constant influx of micrometeoroids. That said, a howardite by definition is composed of substantial clasts of meteoroids from other bodies and they too have arrived at cosmic speeds, so there is hope to find clast on the moon of parent bodies no longer in existence. The moon may be the last repository for discovering the nature of the Early Bombardment episode 3.85 billion years ago. The lunar soil probably contains pockets of meteorite enriched regolith tilled under the surface by contemporary impacts and subsequently tilled back to the surface by recent impacts. This is the impetus to go to the far side for sample returns. I talked once to Charlie Duke --the only geologist thus far to walk on the moon, about the very topic and he said that they did see small furrows where "rocks" had rolled/bounced along the surface but never the end of a track to see what type rock was sitting there. One small meteorite was recovered in the Apollo Program (Hadley Rill?).(Details anyone?) Didn't it possess impact pockmarks? As to mounting a mission to the moon to recover meteorites, a meteorite not in situ from its parent body may be a curiosity but is far less valuable scientifically than an asteroid sample return mission. I personally would accept either type mission if NASA were willing to send me and bring me back. In fact I have set up a paypal account for donations... for me and my wife....Morgan....Morgan Fairchild -- yeah that's the ticket... I guess we'll have to wait and see for sure but science suggests that substantial "pristine" meteorites will be exceedingly rare on the moon. Elton --- Bob Evans <bobe5531_at_comcast.net> wrote: > Can you imagine hunting meteorites on the moon? > Crustless Diogenites, Eucrites, Howardites > strewnabout everywhere. Received on Fri 01 Sep 2006 01:51:32 AM PDT |
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