Mechanical design and development of SPRITE: a 12U CubeSat with a far-ultraviolet imaging spectrograph

Slated to launch in early 2023, Supernova Remnants and Proxies for Re-Ionization Testbed Experiment (SPRITE) is the first NASA funded 12U astrophysics CubeSat payload and the first orbital astrophysics instrument to operate in the windowless Far-ultraviolet (1000 - 1750 Å) since the deployment of HST-COS. SPRITE is an imaging spectrograph with 10 arcsecond angular resolution, breaking new ground with scientific observations enabled by a compact microchannel plate detector system and advanced protected eLiF mirror coatings baselined for the LUVOIR Surveyor. To provide flexibility and customizability the spacecraft bus and spectrograph are all being designed in house at the Laboratory for Atmospheric and Space Physics. SPRITE features several unique mechanical subsystems such as the pump/purge system for the hermetically sealed detector housing, the release mechanism for the detector door, the release mechanism for the solar array, the solar panel design, and compact rectangular telescope. SPRITE's mechanical design meets all science requirements, the CubeSat specific requirements of commercial 12U dispenser systems, and NASA orbital debris limits. We present an overview of the design and development of the mechanical systems and mechanisms for SPRITE prior to the comprehensive design review (CDR).