From: Jeff Davis (jrd1415@yahoo.com)
Date: Wed Aug 06 2003 - 01:38:39 MDT
--- Kevin Freels <megaquark@hotmail.com> wrote:
> One of the pre-requisites they seem to be searching
> for are planets that exist in a "zone" where there
> could be liquid water.
>
> Now I am not a physicist, but doesn't the fluidity
> of water depend on more than jus tthe distance from
> it's star and the heat from it
<snip>
> It seems to me that the people conducting these
> searches are limiting themselves by putting a
> "habitable" zone around a star.
Righto!, Kevin. There are all manner of unwarranted
assumptions going around, by people with very pinched
imagination, about the "requirements" for life.
In Thomas Gold's The Deep Hot Biosphere
http://people.cornell.edu/pages/tg21/DHB.html
he writes:
There are strong indications that microbial life is
widespread at depth in the crust of the Earth, just as
such life has been identified in numerous ocean vents.
This life is not dependent on solar energy and
photosynthesis for its primary energy supply, and it
is essentially independent of the surface
circumstances. Its energy supply comes from chemical
sources,...
and
Subsurface life may be widespread among the planetary
bodies of our solar system, since many of them have
equally suitable conditions below, while having
totally inhospitable surfaces. One may even speculate
that such life may be widely disseminated in the
universe, since planetary type bodies with similar
sub-surface conditions may be common as solitary
objects in space, as well as in other solar-type
systems.
and
...the "ocean vents", found first in some small
regions of the ocean floor, but now found to be
widespread (2), proved to have an energy supply for
its life that was totally independent of sunlight and
all surface energy sources. There the energy for life
was derived from chemical processes,...
and
It may be that we shall find a simple general rule to
apply: that microbial life exists in all the locations
where microbes can survive; that would mean all the
locations that have a chemical energy supply and that
are at a temperature below the maximum one to which
microbes can adapt.
and
The other planetary bodies in our solar system do not
have favorable circumstances for **surface** life.
but
Many planetary bodies will have temperature and
pressure regimes in their interiors that would allow
liquid water to exist.
and
The surface life on the Earth, based on photosynthesis
for its overall energy supply, may be just one strange
branch of life, an adaptation specific to a planet
that happened to have such favorable circumstances on
its surface as would occur only very rarely...
The deep, chemically supplied life, however, may be
very common in the universe.
----------------------
Read the entire piece for the full story. Great fun.
Best, Jeff Davis
"When I am working on a problem I never think about
beauty. I only think about how to solve the problem.
But when I have finished, if the solution is not
beautiful, I know it is wrong."
- Buckminster Fuller
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