The advent of small launch vehicles has enabled the launch of small satellites on-demand into optimized orbits at affordable costs, leading to a rapid expansion of the small/micro satellite market. However, these small launch vehicles are inherently limited to LEO and currently struggle to support NASA’s push for lunar exploration. ExoTerra’s Solar Electric Propulsion Upper Stage augments small launch vehicles to enable missions to GEO, Trans-Lunar Injection, Earth-Moon Lagrange Points, Lunar Near Rectilinear Halo Orbits, and Low Lunar Orbit. When launched from Virgin Orbit’s Launcher One, it uses 8 km/s of delta-V to transfer up to 150 kg to Low Lunar Orbit, enabling low-cost lunar exploration using small satellites and landers.
During the Phase I effort, ExoTerra and its partners complete a PDR level design of the upper stage by drawing from our Courier SEP micro-satellite design. This prepares us to perform a prototype build in Phase II to raise the system to TRL 6.
The SEP Upper Stage enables NASA to use Small Launch Vehicles to perform several missions. This starts with supporting the Lunar Program by delivering small orbiters and landers to the Moon at low cost and high frequency. This enables systems like affordable Lunar GPS or telecom relay deployment, and CLPS landers to demonstrate technologies on the lunar surface. The system also enables small launch vehicles to deploy small, focused missions, such as those performed by SIMPLEx, throughout the inner solar system as needed.
The SEP Upper Stage has several non-NASA uses. Foremost is the ability to deploy ESPA class satellites to GEO from a Small Launch Vehicle. This benefits both commercial and DoD users. It also supports commercial efforts to send commercial missions to the Moon.