Demonstration of Roman Coronagraph Instrument Star Acquisition in Thermal Vacuum

TL;DR

This paper reports on the NASA Roman Space Telescope's Coronagraph Instrument's star acquisition system, including two methods and results from thermal vacuum tests to verify performance for exoplanet imaging.

Contribution

It introduces two star acquisition methods for the Roman Coronagraph and presents thermal vacuum test results validating their performance in space conditions.

Findings

Successful demonstration of star acquisition in thermal vacuum tests

Validation of system-level performance requirements

Effective active wavefront control using deformable mirrors

Abstract

NASA's Nancy Grace Roman Space Telescope is a flagship astrophysics mission planned for launch no later than May 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 surpass previous space-based and ground-based coronagraphs. This is accomplished using active wavefront control in space with deformable mirrors. CGI requires a star acquisition system capable of acquiring reference and target stars to achieve this goal. This paper describes two CGI star acquisition system methods: EXCAM and Raster Scan. Furthermore, it will detail the results of the CGI thermal vacuum (TVAC) tests conducted to evaluate system-level star acquisition and verify its performance requirements.