JUNE 2002 COMMUNITY WORKSHOP
INFRARED SPECTROSCOPY OF MARS:
FROM THE THEORY AND THE LABORATORY TO FIELD OBSERVATIONS
FULL WORKSHOP REPORT (pdf), including abstracts
Goal. The continuity and timely implementation of the Mars exploration strategy relies heavily on the ability of the planetary community to interpret infrared spectral data. However, the increasing mission rate, data volume, and data variety, combined with the small number of spectroscopists within the planetary community, will require a coordinated community effort for effective and timely interpretation of the newly acquired and planned data sets. Relevant spectroscopic instruments include the 1996 TES, 2001 THEMIS, 2003 Pancam, 2003 Mini-TES, 2003 Mars Express OMEGA, 2003 Mars Express PFS, and 2005 CRISM.
In light of that, leaders of the Mars spectral community met June 4-6 to address the question:
What terrestrial theoretical, laboratory, and field studies are most needed to best support timely interpretations of current and planned visible/infrared spectrometer data sets, in light of the Mars Program goals?
Summary of gaps. This report focuses on identification of critical gaps, particularly those that cannot be filled by individual researchers alone, and does not discuss the relative importance of ongoing research. The two most critical gaps are in coordinated end-to-end field testing and in libraries of spectroscopic data. Three related gaps are in data from terrestrial sites to aid TES and CRISM interpretations, lack of high quality development data to support landers, and delays in funding owing to lack of coordination between R&A proposal dues dates and mission data releases.
The report contains detailed recommendations, the meeting program, list of participants, and abstracts.
FULL WORKSHOP REPORT, including abstracts
SUMMARY OF TWO MOST CRITICAL ITEMS
1. End-to-end testing. Field/rover, airborne/satellite, and telescopic measurements are sensitive to very different effects, and these differ from those present in the laboratory. Thus a convincing determination of uncertainties as related to studies of Mars requires demonstration through coordinated "end-to-end" field testing. This should proceed in light of our current best understanding of martian mineralogy and environment, using:
- (1) Data sets of appropriate terrestrial analog sites that are measured with both geometric and spectral fidelity as close as possible to landed and orbital flight instruments;
- (2) Interpretation using spectral libraries and theoretical work as applied to data of Mars;
- (3) Reporting interpretations at a community workshop, including a "blind test" (with minimal foreknowledge of the test site or ground truth);
- (4) Validation through ground truth.
Coordination through an independent steering group is critical in order to maintain and facilitate a clear focus on addressing the central questions. This is imperative to support timely interpretations and to plan and manage future flight instruments, but it cannot be achieved by individual researchers alone. Further, in order to achieve results in time to support the current suite of missions, this program needs to begin as soon as possible with adequate and focused funding.
- (1) Test mission protocols and interpretation methods used for flight data;
- (2) Develop theoretical ties and address critical current uncertainties in detectability, uniqueness of identifications, abundance mapping, and atmospheric compensations;
- (3) Prepare the community to interpret flight data in a timely manner;
- (4) Help define and highlight gaps in public spectral libraries, and the importance of the libraries and theoretical work to the interpretation chain.
2. Public libraries of spectroscopic data. Interpretation quality is limited to the quality of the accessible spectral libraries. Current public libraries focus on specific issues or conditions (such as major groups of igneous minerals and terrestrial weathering products, and large particles). Primary gaps include (1) systematic measurements of other weathering products, coatings, a range of surface textures, full particle size ranges; (2) measurements made under simulated Martian conditions; (3) motivating and facilitating a conversion of private libraries into the public domain; and (4) systematic development of fundamental optical constants for modeling. Currently there is insufficient funding and staffing to measure, document and prepare for public release documented digital spectral libraries. It is unclear which R&A program is responsible for developing strong public libraries, and this should be clarified in the appropriate Announcement of Opportunity. Additions and public access should be fostered in cooperation with NASA's Planetary Data System.