Strategies to mitigate effects of pointing error for the TOLIMAN space telescope

The TOLIMAN space telescope is purpose-built to probe our stellar neighbourhood for potentially habitable Earth-like exoplanets. Our novel diffractive pupil design will allow TOLIMAN to detect extremely subtle changes in the positions of stars in a binary system, down to the microarcsecond scale. One of the many challenging factors in the detection of this diminutive astrometric signal is instability in the telescope pointing, known as jitter. This work demonstrates the capability of mitigating the blurring effects of telescope jitter through a forward modelling approach and a new precise optical positioning system. We utilise ∂Lux – a cutting-edge differentiable optical simulation framework built in Jax by our team at the University of Sydney – to model the effects of telescope jitter on the final image. The demanding stability requirements have also inspired innovative engineering approaches, including the design of a piezo-driven tip/tilt system. This methodology enables us to recover the crucial astrometric parameters despite telescope pointing instability, offering TOLIMAN the unique opportunity to observe exoplanetary signatures with unprecedented precision.