Vision and Voyages for Planetary Science in the - Solar System ...

Future Directions for Investigations and Measurements
Key investigations to advance our understanding of geologic processes that have governed Mars’s
evolution include understanding the origin and nature of the sedimentary units by applying physical and
geochemical models, remote and in situ observations of diverse suites of sedimentary materials on Mars,
and laboratory investigations of Mars analog materials to study the formation, transport, and deposition of
sedimentary materials by fluvial, Aeolian, impact, and mass wasting processes. Major advances will come
from the investigation of the petrologic, mineralogic, isotopic, geochronologic properties of rock suites in
returned martian samples, martian meteorites, and Mars analog materials in order to understand
environmental conditions and habitability over time, the history and timing of core separation and
differentiation, past tectonic processes, Mars’s past and present geophysical properties, the bulk, mantle
and core compositions, and the relationship between martian meteorites and igneous rocks on Mars’s
surface. Key investigations are needed to explore the distribution and source of reduced carbon
compounds in the surface and atmosphere. Better characterization of the distribution of carbon dioxide
and water on a long-term scale and more detailed examination the polar layered deposits and layered
sedimentary rocks for the record of the present-day and past climate will both help to better understand
volatile budgets and cycles.
Refined criteria need to be developed for selecting sample suites for return to Earth, including
sample suites for sensitive analysis of biomarkers (e.g., CHNOPS elements), suites representing diverse
sedimentary environments with possible rapid burial, suites showing chemical gradients formed through
alteration, oxidation, neutralization and precipitation, and those from aqueous alteration environments
including hydrothermal suites that show potential for preserving biosignatures; igneous suites; regolith
samples, and atmospheric. Finally we need advances in technologies to better collect, handle, curate,
analyze, and study martian materials, meteorites and analog samples on all scales in a range of
environmental conditions, and in the context of new experimental and theoretical data, and planetary
protection guidelines.
Characterize the Structure, Composition, Dynamics, and Evolution of Mars’s Interior
The interior of Mars will be investigated by characterizing the structure and dynamics of the
interior, determining the origin and history of the magnetic field, and determining the chemical and
thermal evolution of the planet. Unfortunately, there has been little progress made toward a better
understanding of the martian interior and the processes that have occurred. Probing the interior is best
done through a network of geophysical stations, and such a network has not yet been implemented at
Mars.
Important Questions
Some important questions concerning the structure, composition, dynamics, and evolution of
Mars’s interior include the following:
• What is the interior structure of Mars? How are core separation and differentiation processes
related to the initiation and/or failure of plate tectonic processes on Mars?
• When did these major interior events occur, and how did they affect the magnetic field and
internal structure? What is the history of the martian dynamo? What were the major heat flow
mechanisms that operated on Early Mars?
• What is Mars’s tectonic, seismic, and volcanic activity today? How, when, and why did the
crustal dichotomy form? What is the present lithospheric structure? What are the martian bulk, mantle
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