Demonstration of Roman Coronagraph Instrument (CGI) Star Acquisition in Thermal Vacuum (TVAC)

NASA’s Nancy Grace Roman Space Telescope is a flagship astrophysics mission, planned for launch in 2027. The Coronagraph Instrument (CGI) aboard Roman will demonstrate the technology for direct imaging and spectroscopy of exoplanets around nearby stars and starlight suppression that surpasses previous space-based and ground-based coronagraphs by using active wavefront control in space with deformable mirrors. To achieve this goal, CGI requires a star acquisition system to acquire both reference and target stars. This paper will describe two different methods of CGI star acquisition system: ExCAm and Raster Scan. Furthermore, it will detail the results of the CGI thermal vacuum (TVAC) tests conducted to assess system-level star acquisition and verify its performance requirements.