Jet Propulsion Laboratory, California Institute of Technology,
Pasadena, CA 91109, U.S.A.
George R. Rossman
California Institute of Technology, Division of Geological and
Planetary Sciences, Pasadena, California 91125, U.S.A.
GEOST, Inc., Tucson, AZ 85741, U.S.A.
mineralogy can be revealed through a variety of remote sensing and in situ
investigations that precede any
for eventual sample return.
review those techniques, and focus on the capabilities for on-surface in situ
examination of Mars, Venus, the
Moon, asteroids and other bodies.
the last decade, Raman spectroscopy has continued to develop as a prime
candidate for the next generation of in
planetary instruments, as it provides definitive
compositional information of minerals in their natural geological
continuous-wave Raman spectroscopy using a green laser suffers from
fluorescence interference which can be large (sometimes saturating the
detector) particularly in altered minerals which are of the greatest
interest. Taking advantage of the fact that fluorescence occurs at a
than the instantaneous Raman signal, we have developed a time-resolved
that uses a streak camera and pulsed miniature microchip laser to
time resolution. Our ability to observe the complete time evolution of
and fluorescence spectra in minerals make this technique ideal for
of diverse planetary environments, some of which are expected to
if not overwhelming fluorescence signatures. We discuss performance
and present time-resolved pulsed Raman spectra collected from several
and Mars relevant minerals. In particular we have found that
spectra from fine grained clays, sulfates, and phosphates exhibited
signatures, but high quality spectra could be obtained using our time