Available volumes of nanosats such as CubeSats impose physical limits to the telescope diameter, limiting achievable spatial resolution and photometric capability. For example, a 12U CubeSat typically only has sufficient volume to host a 20 cm diameter monolithic telescope. In this paper, we present recent advances in deployable optics to host a 30 cm+ diameter telescope in a 6U CubeSat, with a volume of 4U dedicated to the payload and 2U to the satellite bus. To reach this high level of compactness, we fold the primary and secondary mirrors for launch, which are then unfolded and aligned in space. Diffraction-limited imaging quality in the visible part of the spectrum is achieved by controlling each mirror segment in piston, tip, and tilt. In this paper, we first describe overall satellite concept, we then report on the optomechanical design of the payload to deploy and adjust the mirrors. Finally, we discuss the automatic phasing of the primary to control the final optical quality of the telescope.
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