Warm Mars

James Nicoll wrote:

[Yeah, I got a new up to date Mars text]

POD: 500 million BP

A rock that would have triggered the collapse of the Martian
atmosphere misses Mars. As a result the rather fragile balance on
Mars is preserved. Mars remains a world with a thick atmosphere,
composed mainly of CO2, an open sea covering a third of the world,
filled with (although single celled) life.

Note:

Quoted excerpts from 'Sky and Telescope' -
December, 2004, page 22, 'New Evidence for
Mars Oceans (and for Life?)' - R.N.

'... images taken by the THEMIS instrument
aboard NASA's Mars Odyssey orbiter ...
have identified two previously unseen
branching valley networks that are
reminiscent of river-valley networks on
Earth. ... estimates an age of about
2.9 to 3.4 billion years for these
features ... tributaries are tightly
and evenly crammed together, like those
formed by rainfall on Earth. ... If it
rained on Mars, did water collect to
form lakes or oceans? NASA's rover
Opportunity found compelling evidence
for surface water at Meridiani Planum
(October issue, page 16). But how
large was this body? Brian M. Hynek
.... writes in September 9th Nature
that this material covers an area the
size of the state of Arizona. ... If
Mars had oceans, they should have left
behind vast deposits of carbonates
when the water evaporated. But
observations by Mars Global Surveyor's
Thermal Emission Spectrometer have
found only traces of carbonates. In
September 23, Nature, Alberto G.
Fairen explains why a Mars that
once had oceans could lack carbonates.
If Martian oceans were laced with
sulfates and iron, the water would
have been mildly acidic ... Acidity
would have prevented carbonates from
precipitating out of the water. ...'

What happened to the CO2 or water?

(It froze on the poles? Mars is
now in an ice age? It got precipited
out elsewhere by other means or got
buried under other rocks? It
dissociated into space by various
methods? Who knows?)

Other possible ATL Mars scenarios:

An object about the size of Mars or
larger forms in the Asteroid Belt. It
collides with Mars with properties
similar to the Mars in our time line
in a non-destructive fashion and merges
to form a body of about .2 Earth mass
about 3 billion years ago. Oceans
again form with a denser atmosphere,
and life is seeded from asteriods
resulting from meteorite impacts
on Earth. Life develops from it
on Mars.

Substitute the asteroid planet for a
large outer solar system moon consisting
mostly of ice.

Increase the mass of Mars.

Get Dr. Who to seed Mars with ginger cats
some time in the past.

Some of the micro-
organisms produce methane, which is a powerful greenhouse gas, as
are CO2 and water, all of which can be found in Warm Mars'
atmosphere.
...
Anyone want to play Build the Ecology?

When did the surface of Mars turn red?

That seems like a lot of iron.

1: Say, can volcanism be helped along by lubricating rocks with water
the same way plate tectonics can?

2: Note to self: do not bring this to Earth.
--
http://www.cic.gc.ca/english/immigrate/
http://www.marryanamerican.ca
http://www.livejournal.com/users/james_nicoll
Crossposted to sci.astro.

That seems like a lot of iron.


It is

PLANETARY COMPOSITION
Crust and Surface: Mars' surface is composed mostly of iron-rich
basaltic rock (an igneous rock). Mars has a thin crust, similar to
Earth's.

Mantle: Silicate rock, probably hotter than the Earth's mantle at
corresponding depths.

Co The core is probably iron and sulphides and may have a radius of
800-1,500 miles (1,300-2,400 km). More will be known when data from
future Mars missions arrives and is analyzed.

MASS AND GRAVITY
Mars' mass is about 6.42 x 10^23 kg. This is 1/9th of the mass of the
Earth. A 100-pound person on Mars would weigh 38 pounds.
http://www.enchantedlearning.com/sub.../planets/mars/