The PUEO star camera: An astrometric camera for sensitive daytime high-altitude scientific balloon radio experiments.

Star cameras were initially developed in the 1960 primarily for defense and satellite navigation. While commonly utilized on satellites, their application to high-altitude balloon flights presents unique challenges when extracting stars from a variable and high scatter background. Atmospheric scattering and mesospheric clouds pose additional hurdles for accurate star field observations and make background subtraction and stray light mitigation critical features of a star camera design used in high altitude balloon experiments. Additionally the presence of highly sensitive radio payloads in scientific high-altitude balloon flights necessitates shielding the star tracker from contaminating the radio background. This work presents the innovative design of a star camera employed in the Payload for Ultrahigh Energy Observations high-altitude balloon experiment (PUEO).