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

• Determine the mass and energy budget of the PLDs and how volatiles and dust have been
exchanged between polar and non-polar reservoirs.
Mission Design
The orbiter mission scenarios were a small orbiter with two payload options, and a medium-size
orbiter combining most of the payload options from the small orbiters. Also investigated were a small
stationary lander and a small-/medium-class stationary lander with a meter-scale drill. The final mission
scenario was for medium-class rover with an ice sampler/rock corer, similar to the one envisioned for the
Mars Astrobiology Explorer-Cacher, as well as spectrometry instruments.
Mission Challenges
While no formal risk assessment was conducted for this study, it identified several areas of
necessary or beneficial technology development. For orbiters, Ka-band telecommunications were
envisioned, pending implementation with the Deep Space Network. All lander options assumed the
availability of telecommunications relay orbiters. In addition, all landers considered in the study were
likely to require precision-guided entry, pending demonstration by the Mars Science Laboratory. Some of
the missions considered would also benefit from the Advanced Stirling Radioisotope Generators, which
are currently under development and may be subject to reliability and logistics issues regarding the
availability of plutonium-238.
Conclusions
The variety of mission concepts discussed covered a significant breadth of options for exploring
Mars’s polar-layered deposits. No prioritization between these options was detailed, but the study served
to illustrate the trade-space studies and instrumentation options for each of the concepts.
GANYMEDE ORBITER
A mission concept study performed by NASA’s Jet Propulsion Laboratory
Overview
The purpose of this full mission study was to develop an architecture suitable to perform a
scientifically viable Ganymede orbiter mission and to determine the feasibility of a NASA-only
Ganymede mission in case the ESA Jupiter Ganymede Orbiter is not realized. Increased mission duration
and modest enhancements to the flight system were also considered to accommodate enhanced payloads
for a “Baseline” and an “Augmented” mission.
Science Objectives
• Further characterize Ganymede’s subsurface ocean.
• Investigate Ganymede’s geology including history, tectonism, icy volcanism, viscous
modification of the surface, and the nature of surface contact with the ocean.
PREPUBLICATION COPY—SUBJECT TO FURTHER EDITORIAL CORRECTION
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