Dear colleagues,
        my planetary science cohorts at Caltech have asked that the
following announcement be passed on to petrology/geochemistry list servers,
including Isogeochem.  The meeting it describes will focus on strategies
one could use to detect 'biosignatures' in the modern Martian atmosphere.
Please contact Mark Allen (GPS division, Caltech) or follow the listed
website link for more information.

John Eiler

________________________________________

Mars Atmospheric Chemistry and Astrobiology (MACA) Workshop

California Institute of Technology, Pasadena, California, USA

December 17-19, 2001

The California Institute of Technology and the Jet Propulsion
Laboratory are hosting a multi-disciplinary workshop to identify what
observations of the composition of the Mars atmosphere would allow
the detection of extant subsurface life, remnants of life, or
signatures of past climate supportive of life. A key question is how
to distinguish between actual biosignatures and atmospheric
composition resulting from volcanic emissions and other
non-biological natural processes that might be occurring on Mars.

Members of the scientific community are invited to participate in
plenary session discussions and present poster talks. The proceedings
of the workshop will be published.

Further information may be found at the workshop website
             (http://www.gps.caltech.edu/meetings/MACA).
Registration will be through this website.

The NASA Astrobiology Institute will entertain requests for travel
support. See the workshop website for additional details.

(Please distribute this notice to your colleagues.)