Last year at this meeting we described a computer application (Brown and Storrie-Lombardi, 2006),
the Mars Reconnaissance PRISM or MR PRISM, designed to analyze hyperspectral data collected
by the Compact Imaging Spectrometer for Mars (CRISM). The application links the spectral,
imaging and mapping perspectives on the CRISM dataset by presenting the user with three different
ways to analyze the data. At this time last year, CRISM was still in calibration mode and we
presented data from ESA's OMEGA instrument to demonstrate the functionality of MR CRISM.
A primary goal in developing this application is to make the latest algorithms for detection of
spectrally interesting targets available to the Planetary Science community without cost to the
individual investigator and with a minimal learning barrier. This would enable the community to
look for Mars surface targets such as ices, hydrothermal minerals, sulfate minerals and hydrous
minerals and map the extent of these deposits. The CRISM team has now provided significant data
sets to our community. We have used one such data set to conduct a study on an exposed water ice
mound. We review here our results on observations made of a ~36km diameter crater, recently
named Louth, in the north polar region of Mars (at 70°N, 103.2°E). High-resolution imagery from
the instruments on the Mars Reconnaissance Orbiter spacecraft were used to map a 15km diameter
water ice deposit in the center of the crater. The water ice mound has surface features that include
roughened ice textures and layering similar to that found in the North Polar Layered Deposits. We
describe the data analysis process including detection and mapping of hydroxyl mineral signatures
using the MR PRISM software suite.
MR PRISM is currently in the prototyping stage. Future additions planned include a Bayesian
analysis engine, the capacity to handle atmospheric correction routines provided by the CRISM
team, the ability to display MOC, THEMIS and HiRISE data and eventually the ability to run on a
distributed network to speed up processing of large image cubes. When the software is released to
the general community, we hope its embedded scripting language, 'Groovy', will make it the 'front
end' for many more sophisticated algorithms from all branches of Mars research.
We describe a computer application designed to analyze hyperspectral data collected by the Compact Infrared Spectrometer for Mars (CRISM). The application links the spectral, imaging and mapping perspectives on the eventual CRISM dataset by presenting the user with three different ways to analyze the data. One of the goals when developing this instrument is to build in the latest algorithms for detection of spectrally compelling targets on the surface of the Red Planet, so they may be available to the Planetary Science community without cost and with a minimal learning barrier to cross. This will allow the Astrobiology community to look for targets of interest such as hydrothermal minerals, sulfate minerals and hydrous minerals and be able to map the extent of these minerals using the most up-to-date and effective algorithms. The application is programmed in Java and will be made available for Windows, Mac and Linux platforms. Users will be able to embed Groovy scripts into the program in order to extend its functionality. The first collection of CRISM data will occur in September of 2006 and this data will be made publicly available six months later via the Planetary Datasystem (PDS). Potential users in the community should therefore look forward to a release date mid-2007. Although exploration of the CRISM data set is the motivating force for developing these software tools, the ease of writing additional Groovy scripts to access other data sets makes the tools useful for mineral exploration, crop management, and characterization of extreme environments here on Earth or other terrestrial planets. The system can be easily implemented for use by high school, college, and graduate level students.
The European hyperspectral imaging instrument OMEGA has been in operation around Mars since early 2004. OMEGA has constructed imaging maps covering almost the entire Martian surface (Bibring et al., 2005). The OMEGA science team have identified a 60 x 200km deposit rich in Ca-sulfates, most likely gypsum, near the Martian northern polar cap (Langevin et al., 2005). They have suggested an evaporation origin linked to varying Martian obliquity, warming the poles during periods of high obliquity, causing the melting of water ice, and then evaporation of this ephemeral water, leaving behind salty brines adjacent to the frozen ice cap. In 2004, a hyperspectral imaging survey of the Yilgarn Craton was carried out using the HyMap instrument (Cocks et al., 1998). The Yilgarn is a good Mars analog due to the presence of ultramafic-mafic volcanic basalt flows. We have therefore analysed this hyperspectral coverage of the evaporite deposits of the Yilgarn Craton to compare an accessible, Earth-based evaporate analog with the Mars sulfate deposits. Using standard hyperspectral analysis methods, we have mapped gypsum in Western Australian dry lake evaporite deposits near Kalgoorlie. In the future, we shall use an absorption band modelling method (Brown et. al., 2005) to determine the shape, position and intensity of absorption bands that are due to sulfates. Fieldwork in this area has enabled a laboratory based evaluation of hand samples of gypsum taken from the Western Australian deposits. Evaluation of this data and comparison to future Martian hyperspectral data will lead to a greater understanding of the hydration state and cation type of Martian sulfate deposits.
Proposed geochemical histories for the evolution of Mars offer the possibility that the planet may have experienced conditions remarkably similar to those faced by life on Earth during Archean and Proterozoic eons. For almost two billion years microbial mat communities dominated by photosynthetic cyanobacteria were the dominant life forms on Earth. Descendents of these complex communities and the fossil remnants of their ancestors can be found today in Northwestern Australia. These sites offer a unique testing ground for developing integrated remote and in situ methods for identifying sites of geobiological interest during exploration of Mars, the Jovian or Saturnian satellites, or neighboring extra-solar planetary systems. We are currently performing remote and in situ analyses of spectral and image data from the Trendall locality of NW Australia, an area rich in geobiological targets including hydrothermally altered basalts, fossil stromatolites and pillow basalts. We discuss the early results of employing cluster analysis, Bayesian probabilistic estimators, and complexity analysis techniques to analyze remote and in situ photographic and spectral data. The techniques presented offer a systematic methodology for both the remote selection of landing sites most likely to contain targets of geobiological interest and the in situ identification of aqueous or biologically altered samples.
Conference Committee Involvement (4)
Instruments, Methods, and Missions for Astrobiology XII
4 August 2009 | San Diego, California, United States
Instruments, Methods, and Missions for Astrobiology XI
12 August 2008 | San Diego, California, United States
Instruments, Methods, and Missions for Astrobiology X
28 August 2007 | San Diego, California, United States
Instruments, Methods, and Missions for Astrobiology IX
14 August 2006 | San Diego, California, United States