A General Purpose Astronomy Small Satellite: An approach to low-cost space telescope design using space-qualified ground telescopes

Abstract

The General Purpose Astronomy - Small Satellite (GPA-SS) project studied the feasibility of developing a useful space telescope with a cost to launch below $100 million. An optical telescope assembly (OTA) designed for ground use is proposed for use in a space mission in order to take advantage of the economies of scale in existing mirror fabrication processes. This paper details the additional design, manufacture and test tasks required to flight-qualify the ground telescope. A near-infrared imaging space telescope was costed as a potential mission. Key subsystems were designed at a conceptual level. This design was used both to estimate subsystem costs and to inform the science achievable from a given telescope design. Subsystem costs were estimated from the design through a combination of previously published cost estimating relationships and vendor quotes. This paper concludes that the space-qualification of an existing ground telescope is a potential approach for making significant cost savings when designing a low cost space telescope. Additional work on design and cost estimation around the framework presented in this paper could be undertaken to add certainty to the cost estimate.