Oort Cloud Comet and Interstellar Object Science Smallsat Technical Capabilities Programmatic Recommendations

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National Aeronautics and Steve E. Matousek Space Administration (Corresponding Author) Benjamin P. S. Donitz Close Flyby and Characterization of Julie C. Castillo-Rogez Tibor Balint Jet Propulsion Laboratory California Institute of Technology Long Period Comets like C/2017 K2 Contact: steve.matousek@jpl.nasa.gov

Oort Cloud Comet and

Interstellar Object Science COMET C/2017 K2, ORIGINATED 3/4 LIGHTYEAR AWAY, Both OCCs and ISOs are witnesses of early stellar system formation and early evolution PICTURED AT 10 AU FROM THE SUN IN 2017 • OCCs are believed to have formed at the end of the protoplanetary disk • The preferred origin for ISOs is the ejection of small bodies (e.g., comets) during giant planet migration or perturbation of debris disks, the equivalent of Kuiper Belt and Oort cloud in other stellar systems OORT CLOUD Chemical, isotopic, and mineralogy observations are needed to infer constraints on the nebula environments in which OCCs and ISOs formed HALE-BOPP PICTURED 1995. C/2017 K2 WILL LIKELY EXHIBIT SIMILAR • Combined with orbital dynamics modeling, chemical constraints can also help ACTIVITY AT PERIHELION IN 2022 narrow down the possible stellar systems from which ISOs oiginated

SmallSat Technical Capabilities SOLAR SYSTEM

SmallSats are becoming increasingly capable of deep space exploration.

• Shorter development schedules allow for response missions

• Miniaturized instruments including high resolution optical imagers and remote spectrometers are enabling profound science

• Deep space propulsion enables trajectory correcting maneuvers

• On-board computing resources enable the autonomous selection of high-value science for downlink back to Earth MARS VENUS A 2019 study at JPL concluded that two SmallSats could feasibly be built FEBRUARY 2022 LAUNCH to encounter a comet like C/2017 K2 and return high value science SUN EARTH • Project timelines of 18-24 months are feasible MERCURY

• High resolution optical imagers provide compelling science return

• Encountering OCC and ISO generally require very large amount of launch energy, often requiring a dedicated large launch vehicle

• Encountering C/2017 K2 required >58 km2/s2

• Large spacecraft are often too

Programmatic Recommendations

Development and launch a SmallSat to encounter an OCC or ISO is SPACECRAFT 1 feasible but there is no programmatic strategy for reactive missions REACTIVE EXPLORATION • SIMPLEx cost cap is too low for a mission of this type SPACECRAFT WITH A HIGH GAIN ANTENNA TO • Cadence of NASA solicitations is not conducive to reactive missions TRANSMIT SCIENCE DATA BACK TO EARTH In light of the 2019 JPL study, the authors recommend NASA revisit funding mechanisms and including opportunities for reactive missions SPACECRAFT 2

• Mechanisms to unlock resources to start projects within months AUG 2022 ENCOUNTER of object discovery to meet strict launch periods (2.1 AU FROM EARTH, 2.3 AU FROM SUN) • Leeway to begin procuring long-lead items prior to KDP-A so that timeline and reviews do not become burdensome to mission feasibility

• Revamping of programmatic considerations to allow for shorter development schedules and higher launch energies to reach newly discover OCC and ISO