Near-Term Strategies to Rendezvous with an Interstellar Object

Interstellar Objects (ISOs) offer a unique opportunity to answer fundamental questions about the nature of objects that originate outside our solar system. Only two members of this new class of mission target have been identified: asteroid 1I/`Oumuamua in 2017 and comet 2I/Borisov in 2019. Many more are expected to be found with the introduction of the Vera C. Rubin Observatory motivating the formulation of mission concepts to investigate future ISOs. While fast flyby missions are technically feasible today, rendezvous missions that orbit or even land offer the only means for literal ground truth into the nature of these objects. Mission design and propulsion capability are current challenges due to the brevity of ISO paths through the Solar System. These challenges may be overcome with a trade space of detection capabilities, launch vehicles, trajectory designs, and near-term spacecraft technology development. In particular, the combination of Jupiter gravity assist and nuclear electric propulsion provides the highest likelihood of delivering a spacecraft to match the orbit of an ISO.