Analysis of alternative systems for orbit alteration of near-Earth asteroids and comets

The present study examines various systems for altering the orbit of near-Earth asteroids and comets (ECOs - Earth Crossing Objects). The aim of such orbit alteration is to prevent a collision between these celestial bodies and the Earth, since depending on the size of the ECO, this can have catastrophic consequences for the entire terrestrial biosphere. Whereas small ECOs can be deflected at relatively low cost fiven a sufficiently long time, ECOs with diameters of several kilometres present a serious problem. This also holds in particular for long-period comets. In addition to a description of possible deflection systems in conjunction with the creation of mass models, the systems are analysed as to their effectiveness and compared with one another. The upper limit of the deflection possibilities is determined by the maximum available payload of the carrier systems. A simple system design of a typical mission is also drawn up for four deflection systems regarded as suitable (of which two are non-nuclear).