Re: Comets to Mars?

On Mon, 10 Nov 2003, Hop David wrote:
|But now in John S. Lewis' _Rain of Iron and Ice_ I read about
|atmospheric erosion by meteorites.

Hmm..  I think I'll check out http://www.amazon.com and see if
it is available there.

|Most the atmosphere the other side of a tangent plane touching the
|Martian sphere at point of impact is sent into space.

Is the atmosphere permanently lost, or does it eventually come
back down?  I'd think that loss of atmosphere is something that
is undesirable; does this still happen if the meterorites are
broken up (with nuclear bombs, so they become fragmentary or
shatter) before they enter Mars' atmosphere?

|So would comets add or subtract to Mars' atmosphere?

How much mass can you count on coming from those comets that you can
locate and drive to the near vicinity of Mars?  Don't you lose some
of that mass, just driving the comets into Mars's orbit?

|By my calculations KBOs sent on a Hohmann transfer orbit to Mars
|would come into Mars orbit at about 9 km/sec. Mars gravity would add
|another 5. So I believe a KBO would hit Mars at around 14 km/sec.

If you don't first break the meteorites up before entry, you are
going to get a lot more surface material mixed into the atmosphere,
but if you can successfully break them up first, the atmosphere
itself is going to be the only thing to slow down the meteorites'
entry.