Cool Stars 14 - Submitted Abstract # 388
This version created on 13 October 2006

Photochemical effects on terrestrial planet atmospheres


Antigona Segura, JPL/Caltech
James Kasting, Pennsylvania State University
John Scalo, University of Texas
Victoria Meadows, IPAC/Caltech
Martin Cohen, University of California, Berkeley

The particular shape of the UV radiation emitted by low mass stars may
produce interesting chemical changes in atmospheres like that of
present Earth.  Simulations performed by Segura et al.  (2005) show
that given the same flux of biogenic compounds as on the present
Earth, these chemical species may have longer residence times in the
atmospheres of planets around active and quiescent M main sequence
stars.  This could make it more feasible to simultaneously detect two
or three biogenic compounds, which would provide strong evidence for
the existence of extraterrestrial life.  Hence, M stars may make
interesting targets for TPF or Darwin.  Reference Segura et al.  2005
Astrobiology 5(6), 706-725.  

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