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

landing in the small southern lakes challenging; all architectures thus assumed landings on the much
larger Kraken Mare in the north. A requirement to target Kraken Mare constrained the trajectory of the
DTE mission since the likely launch opportunity left little time before Earth would no longer be in view
from the lake surface. Consequently, a high C3 trajectory was required for this architecture to reduce
travel time to Titan, increasing launch mass and launch costs.
Conclusions
The exploration of Titan’s hydrocarbon lakes has high scientific potential and the Titan lake
lander concepts appear feasible. However, based on the costs and the relatively limited science scope of a
stand-alone lake probe without the orbiter and balloon elements, the stand-alone lake probe concepts were
judged to be lower priority than a lake probe which was an element of a flagship mission, or some of the
other mission concepts studied. The cryogenic environment and lack of heritage in lake probe design
necessitates strategic investment in technology development, including cryogenic sample acquisition and
handling.
CHIRON ORBITER
A mission concept study performed by NASA’s Goddard Space Flight Center.
Overview
The purpose of this rapid mission architecture study was to determine several options for
delivering a useful payload into orbit around Chiron. The five options discussed focused mainly on the
propulsion and trajectories needed to place a satellite, with a given science package, into orbit around
Chiron.
Science Objectives
• Observe current geologic state and composition of surface and infer past evolution and
relative importance of surface processes.
• Observe and measure the sporadic outgassing activity and determine the composition of
outgassed volatiles.
• Characterize bulk properties and interior structure.
Mission Design
The majority of the engineering work for this study was spent on propulsion, power, and
trajectory trades to define how the science payload could be delivered to Chiron within the given
constraints, leaving less resource for the definition of the science package. Several trajectories for flights
between Earth and Chiron including both direct and flyby orbital trajectories were examined. Launch was
determined to occur between 2019 and 2025 depending on propulsion option, with a cruise phase duration
between 11 and 13 years.
None of the preliminary propulsion solutions deliver an acceptable mass to Chiron with an 11year
transit time; however, five propulsion options were determined that could deliver acceptable masses
into Chiron Orbit with a 13-year transit time as the baseline.
PREPUBLICATION COPY—SUBJECT TO FURTHER EDITORIAL CORRECTION
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