February 15, 2004

George wrote:

http://www-curator.jsc.nasa.gov/cura...rchForLife.htm

Look at the structure of the globules. While they are smaller by an order
of magnitude,
and flattened, as a result of their formation in very narrow fractures and
fissures,
they have the basic structure, an inner precipitate, and an iron rich
outer coating.
Perhaps the spherules are just the final result of a process where the
biogenic
precipitation process is allowed to complete its cycle.

You could certainly try to make that case, although based on what evidence
that the ROVER has collected, I have no idea.

You certainly don't.

Based on the evidence that
the rover has thus far collected, it is far more likely that the spherules
are simply volcanic/impact related.

Mineral laden ice sheets obviously would be volcanic/impact related, as I just pointed out.

In fact, I think it is far more likely
that this is the case.

It's nice that we agree, but the problem remains, the process by which the spherules were
formed.

Certainly there is evidence now for a biogenic origin of terrestrial
banded iron
formations.

No doubt. But that is not what we are talking about here.

We certainly are - hematite.

Whether or not the spherules rain out of a water vapor and mineral rich
sky, or out of
a water and mineral rich surface, is almost irrelevant. Precipitation is
required for
mineral rich ice sheet formation, and this is what I see here. Regardless,
this
indicates a very wet Mars in the distant past, and a very icy Mars in the
present.

So where's the ICE?

Under the desiccated regolith. Look at the orbital images. In particular, look at the
larger craters. By simply looking at the rover images you suffer from tunnel vision.

I would recommend that you read the following article. It is worthwhile, and
addresses some of the same issues:

http://www.space.com/missionlaunches...es_040211.html

Space.com eh?

The article is nonsense, if we are looking at biogenically precipitated spherules, that
underwent subsequent geological transformation, then they may certainly be classified as
'fossils'. Perhaps you can ignore ALH80001, but doing so puts you firmly into the
'crackpot' category. As far as I know, however, speculation is allowed in the scientific
method, whereas outright dismissal is not.

Thomas Lee Elifritz
http://elifritz.members.atlantic.net