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Re: (meteorobs) Probabilities of REALLY BIG fireballs...
I am just theorizing here, but two possibilies are
the mass struck an ice sheet, and therefore the crater disappeared when the
sheet retreated
or the mass was transported by the ice and/or the ice scraped the crater.
Darryl Pitt wrote:
> Hi George-
>
> What troubled me was that the main mass of the stone Jilin (approx. 2 tons)
> left an impact crater nearly twenty feet deep, yet here is this 14+ ton
> iron leaving no evidence of any crater whatsoever. Even taking into
> consideration the variables of speed, angle of entry, the material being
> impacted, etc., it seemed that there should have been some remnant of a
> crater...and there wasn't. Assuming that the ice-age deposit theory is
> incorrect, it had to be erosion be the max. Thanks for helping me out with
> this.
>
> Darryl
>
> >
> >Darryl, Reading in O. Richard Nortons Book entitled Rocks From Space, he
> >states that a 10 ton meteorite had only 6% of it's cosmic velocity left when
> >it hit the ground. And a 100 ton meteorite retains nearly half of it's cosmic
> >velocity when it hits. A 15 ton meteorite would probably be going about 10%
> >cosmic velocity....roughly going 7,500 mph? I wouldn't want to get in it's
> >way...but I don't think you are going to see anything like the crater in
> >Arizona? I guess when it hit the ground, it probably did make a small crater,
> >but nothing that would be noticeable by now if the fall occurred during the
> >last Ice Age. Probably just some dirt excavation and not much more? Active
> >erosion probably erased any traces of a crater?
> >George Zay
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