Aerocapture Solutions for Uranus Flagship-class Orbiter and Probe

Recent planetary mission assessments, such as the 2022 Planetary Science Decadal Survey released by the National Academies of Science, have focused on the need for a flagship-class mission to the Ice Giant planets, particularly Uranus. The Uranus Orbit and Probe mission proposal was used by the National Academies of Science as the baseline while making its recommendation as the top flagship-class mission for NASA in the 2020-2030\'s. This mission which was based on a launch date of 2031 or 2032, used a fully-propulsive orbit insertion maneuver at Uranus (requiring 60-70% of total mass for propellant), and reached the planet after 13 years of interplanetary cruise before the 2049 equinox, a goal of the science community. A pre-2033 launch date is required to conduct a necessary Jupiter fly-by as the giant planet will be not be in the proper alignment for a later launch date. However, as the budget constraints of the NASA budget have pushed back the start date of a Uranus mission, a launch date of a flagship mission before 2033 seems unreasonable.

Aerocapture, an orbit insertion maneuver that uses the atmosphere to decelerate, can reduce the propellant load needed for a captured orbit. Additionally, the aerocapture maneuver can decelerate safely while approaching the planet at higher arrival velocities, thus allowing a mission to use a highly energetic trajectory and reduce the cruise time by several years. An aerocapture-enabled solution has launch opportunities in the mid 2030's, including as late as 2038 to reach Uranus by 2049. This paper will discuss the feasibility of an aerocapture option for a Flagship-class mission to Uranus.