From: Mike Lorrey (mlorrey@yahoo.com)
Date: Mon Jul 14 2003 - 10:50:08 MDT
--- Spike <spike66@comcast.net> wrote:
> Mike Lorrey:
>
> ...Secondly, our moon is at least as important as Jupiter at saving
> our
> asses from being nothing but a gravel pit...
>
>
> I don't follow your reasoning here Mike. Why
> would the moon have much affect on the number
> of meteors that hit the earth? Is that what
> you meant? Jupiter mops up most of the interplanetary
> stuff that would otherwise hit the earth. The moon?
> Nah, almost negligible.
Not so. Look at the impact record, especially on the far side of the
moon. If the moon were not so significant, you'd see little variation
between the near side and far side impact records. Instead, the far
side looks like it's suffered multiple cases of chicken pox, cow pox,
small pox, and leprosy.
The moon, having far more angular velocity than Earth, sweeps a
significant volume of space around the earth with it's gravity field.
It is our own little minesweeper. Talk to any of the Near Earth
Asteroid researchers, or any senologist. The Moon is of immense help.
It certainly hasn't protected us from planet killers like
Shoemaker-Levy could have been. That is Jupiter's job. The moon
protects us from Dinosaur-killer events as much as it can.
Any earth-like planet around another star system without a large moon
like ours will suffer far higher frequencies of dino-killer impacts.
Furthermore, as I've detailed before, life is very dependent upon the
fact that the Moon exists at all, since it was created by a grazing
impact of a planetesimal early in Earth's history, which not only
chipped off a significantly large fraction of Earth's original
lithosphere (somewhere about as thick as Venus' is), but blew away a
good fraction of Earth's original Venus-like atmosphere, enough so that
life could evolve at reduced pressures and temperatures.
Without such a planetesimal impact, life would never have evolved here
to the degree it has. Even if complex life evolved, the odds of
intelligent life would be low, and EVEN if intelligent life evolved,
they would never develop the technology necessary to launch spaceships
through a very thick atmosphere that at best would only be reduced to
about 2-3 times our own modern pressure level. They would never see the
stars as we do. On the plus side, they might develop some very
interesting flying technology.
=====
Mike Lorrey
"Live Free or Die, Death is not the Worst of Evils."
- Gen. John Stark
Blog: Sado-Mikeyism: http://mikeysoft.zblogger.com
Flight sims: http://www.x-plane.org/users/greendragon/
Pro-tech freedom discussion:
http://groups.yahoo.com/group/exi-freedom
__________________________________
Do you Yahoo!?
SBC Yahoo! DSL - Now only $29.95 per month!
http://sbc.yahoo.com
This archive was generated by hypermail 2.1.5 : Mon Jul 14 2003 - 10:59:13 MDT