"Hagar" <hagen@sahm,name> wrote in message 
news:H_OdnawFiM0YvffWnZ2dnUVZ_gednZ2d@giganews.com...

That "two comets colliding" theory sounds sort of far fetched ... it's 
like to people,
positioned a mile apart, shooting 22LR bullets towards each other at a 45 
degree
angle and then have them collide in mid air.  Could happen ... in a movie 
perhaps
... but highly unlikely in real life.

But yet, it happens.

With hundreds of millions of asteroids
and billions of years time, these collisions
are common on a planetary time scale.

The fact that we get to SEE such a collision
is what's rare.  Kinda like the Jupiter impact
event in the 90's.