Uranus Cruise and Tour Design Impacts on Science, Cost, and Risk

A detailed trade space analysis of the proposed Uranus Orbiter and Probe mission informs options related to decisions on science, cost, and risk, including design choices of science tour phases, probe and orbiter payload mass, orbiter spacecraft mass, mission duration, and frequency of launch opportunities. The science tour phases flow from baseline and threshold objectives for different scientific disciplines: atmospheres, rings and small satellites, large moons, magnetospheres, and interiors. A broad search of both interplanetary cruise trajectories and Uranian tours produce a trade space of launch opportunities, flight times, and DeltaV that set bounds on spacecraft dry and wet mass. The mission concept employs current technology, such as a Falcon Heavy launch vehicle and a chemical propulsion system. Gravity assists from Venus and/or Earth enable launches throughout the 2030s, when Jupiter is unavailable. The low-risk and low-cost approach would deliver a probe to Uranus and completes a tour of its rings, moons, and magnetosphere within 19 years. A mission duration of 21 years enables multiple close approaches to Uranus that complete the set of objectives called for in the Planetary Science and Astrobiology Decadal Survey.