Mission Analysis and Navigation Design

Abstract

Uranus is one of the most intriguing and unexplored bodies of the Solar System. Its mysteries include its active atmospheric dynamics, its low internal energy, its extreme obliquity, its complex magnetic field, and its ring and satellite system containing possible ocean worlds. As of today, none of the current formation and evolution models can explain all its chemical and dynamical aspects. An in-situ mission to study Uranus' atmosphere could provide answers to this planet's mysteries, enabling the measurement of its deeper layers. A 6 DoF flight simulator was designed, with a focus on identifying the specifications and limitations of its Guidance, Navigation, and Control modules, for feasibly flying in Uranus' challenging atmosphere, and providing new science return. The mission architecture consists of two gliders flying near the planet’s equator and north pole until the 100 bar pressure level for around 13 Earth days, supported by an orbiting spacecraft in a circular, equatorial, and synchronous orbit, for continuous trajectory tracking and relay of the scientific data to Earth ground stations. Due to Uranus’ opaque atmosphere, typical optical navigation sensors such as star sensors, Sun sensors, and imagers are avoided. Instead, the modelled navigation sensors are taken from the payload suite.