The Cryogenic Star Tracking Attitude Regulation System (CSTARS) utilizes a Scientific CMOS (sCMOS) CIS2521F image sensor operating at cryogenic temperatures (77K) to track stars. This is used aboard a sounding rocket for attitude control of the CIBER-2 experiment payload. Standard optical sensors used traditionally for astronomical observations, such as CCD’s, have a low responsivity at cryogenic temperatures. In contrast, CMOS sensors do not exhibit this issue. During flight, the CIBER-2 primary imaging sensors and CSTARS are co-boresighted to the same telescope, all of which are cooled down to cryogenic temperatures. The attitude feed- back provided by CSTARS ensures that CIBER-2 remains aligned with the desired starfield. This work has integrated and tested the necessary control and acquisition system and has determined for the first time the responsivity and minimum detectable star magnitude for a sCMOS image sensor operating at cryogenic temperatures. This paper describes the design, verification, and testing methodologies used in the current work, which are also applicable to similar systems and image sensors. CSTARS was flown along with CIBER-2 on April 16th 2023. The results leading up to and during this flight have proven the readiness of sCMOS sensors for cryogenic space flight operation.

Library of Congress Subject Headings

Star trackers--Testing; Image converters--Testing; Metal oxide semiconductors, Complementary--Thermal properties; Low temperature engineering

Publication Date


Document Type


Student Type


Degree Name

Computer Engineering (MS)

Department, Program, or Center

Computer Engineering (KGCOE)


Dorin Patru

Advisor/Committee Member

Michael Zemcov

Advisor/Committee Member

Marcin Lukowiak


RIT – Main Campus

Plan Codes