A permanent tethered observatory at Jupiter : dynamical analysis

Abstract

Outer planet exploration has always been handicapped by a scarcity of power. The traditional means for powering long-duration space vehicles, solar energy converted to electricity, becomes rapidly ineffective as one travels further from the Sun. Solar intensity diminishes with the square of the distance from the Sun, so that at Jupiter, the nearest of the outer planets and five times more distant from the Sun than the Earth, the solar intensity is only one twenty-fifth its value at Earth. For a mission to Jupiter any extra power will allow the use of instruments which normally cannot be deployed in space because they need too much energy. This is one of the reasons why the JIMO mission of NASA investigated the use of nuclear-powered craft. Electrodynamic tethers could be used in some missions as an interesting alternative to produce the required level of onboard energy. This paper describes the essential dynamical issues arising in the placement of a permanent Jupiter observatory located at one of its inner moonlets (Adrastea, Metis, Amalthea) and sustained by an electrodynamic tether working in the generator regime. The aim of the work is to analyze the dynamical problem posed by such a observatory and also the main aspects related with the orbital dynamics and attitude dynamics of such a Jupiter station. Without a doubt, one of the greatest challenges facing such a mission is the extreme Jupiter radiation environment. This is a serious constraint that can be considered as a significant challenge for current or near-term developing technologies.