Space radio astronomy

Abstract

Space radio astronomy has become of increasing interest for the 1990s and future decades. This paper discusses two areas of radio interferometry: space Very Long Baseline Interferometry (VLBI) and space low-frequency radio astronomy. Two approved space VLBI missions, VSOP and RadioAstron, will be launched in the late 1990s. Studies of successor missions such as ARISE, to be launched after the turn of the millennium, are now under way. In the low-frequency regime, a variety of missions have been proposed. Although none is currently scheduled for launch, the ALFA mission is the leading candidate for a low-frequency mission in the next decade. This paper discusses the basic characteristics and scientific goals of possible future space missions in both the VLBI and low-frequency regimes.