Designing a Potential NASA Fermi Orbit Change

The Fermi Gamma ray Space Telescope, launched in 2008, has over 16 years of operations providing gamma ray (8 keV to 300 Gev) spectra science observations of cosmic phenomena. It continues to provide invaluable research for the astrophysics community which include the study of pulsars, cosmic rays, gamma ray bursts, and coordination with gravity wave observations for neutron star mergers. The Fermi Earth orbit at a 500 x 512 km altitude is subject to collision warnings due to new constellations deployed near Fermi: currently over 7,000 satellites and growing. This paper presents analysis concerning changing Fermi's orbit and associated operational flight dynamics considerations. The cadence of burns and expected fuel use for a proposed orbit raise scenario is examined, ensuring that Fermi should have sufficient fuel for end of life operations. In addition, a Monte Carlo design is presented to capture single maneuver model uncertainty.