First Error Budget Of A Deployable Cubesat Telescope

The volume available on-board small satellites limit the optical aperture to a few centimetres, which limits the Ground-Sampling Distance (GSD) in the visible to approximately 3 m at 500 km. We present a performance analysis of the concept of a deployable CubeSat telescope. This payload will allow a tripling of the ground resolution achievable from a CubeSat imager, hence allowing very high resolution imaging from Low Earth Orbit (LEO).The project combines precision opto-mechanical deployment and cophasing of the mirrors segments using active optics. The payload has the potential of becoming a new off-the-shelf standardised system to be proposed for all high angular resolution imaging missions using CubeSats or similar nanosats. Ultimately, this technology will develop new instrumentation and technology for small satellite platforms with a primary mirror size equal or larger than 30 cm.In this paper, we present the breakdown of the different error sources that may affect the final optical quality and propose cophasing strategies. We show that the piston, tip and tilt aberrations may need to be as small as 15 nm RMS to allow for diffraction-limited imaging. By taking a co-conception approach, i.e. by taking into account the post-processing capability such as deconvolution, we believe these constraints may be somewhat released.Finally, we show numerical simulation of different solutions allowing the aberrations of the primary mirror segments.