Return and abort trajectory optimisation for reusable launch vehicles

Among the future space access vehicles, the lifting body spaceplane is the most promising approach to prevent damage to both the launcher and the payload in case of loss of thrust. The glide performances of the vehicle allow the recovery in both nominal and abort cases. The approach presented is used in the investigation of the unpowered descent paths of a sample vehicle through trajectory optimisation. The vehicle's downrange and crossrange limits are obtained for aborts in multiple flight conditions

Lunar resources: a review

There is growing interest in the possibility that the resource base of the Solar System might in future be used to supplement the economic resources of our own planet. As the Earth’s closest celestial neighbour, the Moon is sure to feature prominently in these developments. In this paper I review what is currently known about economically exploitable resources on the Moon, while also stressing the need for continued lunar exploration. I find that, although it is difficult to identify any single lunar resource that will be sufficiently valuable to drive a lunar resource extraction industry on its own (notwithstanding claims sometimes made for the 3He isotope, which are found to be exaggerated), the Moon nevertheless does possess abundant raw materials that are of potential economic interest. These are relevant to a hierarchy of future applications, beginning with the use of lunar materials to facilitate human activities on the Moon itself, and progressing to the use of lunar resources to underpin a future industrial capability within the Earth-Moon system. In this way, gradually increasing access to lunar resources may help ‘bootstrap’ a space-based economy from which the world economy, and possibly also the world’s environment, will ultimately benefit