M. Leipold, H. Fichtner, B. Heber, P. Groepper, S. Lascar, F. Burger, M. Eiden, T. Niederstadt, C. Sickinger, L. Herbeck, B. Dachwald, W. Seboldt
Heliopause Explorer - A Sailcraft Mission to the Outer Boundaries of the Solar System
Acta Astronautica, Vol. 59, No. 8-11, 2006, pp. 785-796


Solar sail technology holds the promise of enhancing the interplanetary transportation infrastructure for low-cost space exploration missions in the new millennium, by exploiting the freely available, space-pervading resource of solar radiation pressure for primary propulsion. Despite the large distances to the Sun and the reduced solar radiation pressure, fast missions to the outer edge of our solar system belong to the promising mission applications of solar sails. In order to realize such a mission, the sailcraft would first perform a so-called “solar photonic assist”, approaching the Sun to less than 0.3AU thus exploiting the increased solar radiation pressure, to pick up enough orbital energy to enter a hyperbolic orbit. This concept has been extended to a double and triple solar approach which reduces the requirement for very high area-to-mass ratios of the sailcraft. The target distance of the Heliopause Explorer mission is set to 200AU. The science objective was defined as to allow the Heliopause Explorer to perform in-situ observations which can not be obtained within the remaining life time of the two Voyager spacecraft. A first feasibility study was initiated to derive technology requirements for the realization of such a challenging deep space mission.