BIG Impacts (was Re: Vredefort)

[NJPharris@aol.com]

In a message dated 11/25/99 4:54:53 PM Pacific Standard Time, 
sarima@ix.netcom.com writes:

> The Earth is HUGE.   It was struck with a mars-sized body once, early in its
>  history.  It survived

Not only survived, but got bigger and proportionally more massive.  IIRC, the 
earth was only supposed to be about the size of Venus before the impact.  
Plus, most of the light, rocky debris went into the moon, while the heavier 
metals went into the earth, making earth denser than before.  I have 
sometimes wondered whether the extra heavy elements that this impact may have 
provided may be part of the reason why earth has taken so much longer to cool 
than Venus and is still tectonically active.  But I am not a geologist by any 
stretch of the imagination...

Wishing a happy _Meleagris gallopavo_ (Dinosauria: Theropoda) day to all the 
U.S. list members,

Nick P.