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In this paper, we review some of the extant literature on the study of interstellar objects (ISOs). With the forthcoming Vera C. Rubin Telescope and Legacy Survey of Space and Time (LSST), we find that 0. 3 8 − 8 4 'Oumuamua-like interstellar objects are expected to be detected in the next 10 years, with 95% confidence. The feasibility of a rendezvous trajectory has been demonstrated in previous work. In this paper, we investigate the requirements for a rendezvous mission with the primary objective of producing a resolved image of an interstellar object. We outline the rendezvous distances necessary as a function of resolution elements and object size. We expand upon current population synthesis models to account for the size dependency on the detection rates for reachable interstellar objects. We assess the trade-off between object diameter and occurrence rate, and conclude that objects with the size range between a third of the size and the size of 'Oumuamua will be optimal targets for an imaging rendezvous. We also discuss expectations for surface properties and spectral features of interstellar objects, as well as the benefits of various spacecraft storage locations. [ABSTRACT FROM AUTHOR]

Abstract: Since the Moon has no atmosphere it is possible to fly over the surface at very low altitudes without experiencing drag forces. If a spacecraft flying at a low altitude were to fire a projectile into the lunar surface, a second trailing spacecraft could capture material from the resulting cloud of ejecta. This procedure could be repeated over many sites on the Moon with a fresh collector for each location. Eventually, the collector spacecraft would seal its cargo in a reentry vehicle and return to Earth with the samples. Compared with a robotic lander, the advantage of this architecture is the ability to sample locations over the entire Moon, wherever the topography will permit such maneuvers. Our crater ejecta models show that 1–10g of material can be collected from the ejecta curtain of a 2m radius crater at an altitude of 150m, assuming a collector surface area of 1 square meter. We studied numerous means of creating these craters and developed two scenarios: a reduced velocity explosive excavator (EE), and a higher velocity impact excavator (IE). [Copyright &y& Elsevier]