ARISE - A space VLBI mission using an inflatable antenna structure

Abstract

We currently are studying an advanced space Very Long Baseline Interferometry (VLBI) mission called ARISE (Advanced Radio Interferometry between Space and Earth). One or two spacecraft in Earth orbit would form interferometers on baselines to many ground radio telescopes, thus synthesizing a highly sensitive radio telescope with an effective size larger than the Earth’s diameter. ARISE would be a much more sensitive successor t o the first generation space VLBI missions, VSOP and RadioAstron, which will fly in the late 1990s. A critical component of ARISE must be a large antenna in orbit, with a diameter of 25-30 meters, that is capable of operating with high aperture efficiency at frequencies ranging from 5 GHz to 43 GHz; operation (perhaps with lower aperture efficiency) at 60 GHz and 86 GHz is highly desirable. The leading candidate for an inexpensive, reliably deployable telescope meeting these requirements is an inflatable antenna using the technology to be demonstrated in a flight experiment in 1996. This paper reviews the characteristics of present and proposed space VLBI missions, then describes the primary requirements that the ARISE mission places on such an inflatable antenna. 4