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

Comet Sample Return Orbiter
SOURCE: NASA Mission Study (transmitted from Lindley N. Johnson, NASA
SMD/Planetary Science Division)
Scientific Objectives
• Acquire and return to Earth for laboratory analysis a
macroscopic (≥ 500 cc) comet nucleus surface sample
• Characterize the surface region sampled
• Preserve sample complex organics
• Key science themes:
– Physical and chemical conditions in the outer solar
system during its formation
– History of the early solar system through age dating of
cometary grains
– Comets as purveyors of water and organics throughout
the solar system
– Understanding the nature of giant planet cores
Key Parameters
• Payload
– Brush‐Wheel Sample Acquisition System
– Sample Return Vehicle
– Sample Monitoring: sample imagers, temperature and
pressure sensors
– Site Characterization: Narrow Field Visible Imager, Wide
Field Visible Imager, Thermal Infrared Imager
• 17.4 kW (1AU Beginning of Life) Ultraflex power system
(6.3 m diameter)
• Launch Mass: 1865 kg
• Launch Date: 2015 (on Atlas V 521)
• Orbit: 1 km comet orbit + touch and go surface sampling
followed by Earth return
Comet Surface Sample Return
Key Challenges
• Sample Acquisition
– Brush Wheel Sampler needs to be integrated into system
design
– Spacecraft control during touch and go sampling needs
to be addressed
• Mission Design
– Access to surface characterized comets within current
schedule
– Trajectory constraints with 1+1 solar‐electric propulsion
system and Atlas V 521
• System Mass
– Low mass contingencies and launch margin for this
phase of development
Key Cost Element Comparison
Cost Risk Analysis S‐Curve
PREPUBLICATION COPY—SUBJECT TO FURTHER EDITORIAL CORRECTION
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