The Hera near-Earth asteroid sample return mission: science requirements of the sample collector

The Hera mission is a proposed Discovery class mission to collect three samples from each of three near-Earth asteroids. Returned samples would have information on geological context and possibly stratigraphy, would provide fresh regolith, and conceivably samples that would not naturally reach the Earth. During the development of a simple touch-and-go sample collector, questions arose concerning the nature of the samples to be collected, their maximum science return, and the simplest engineering designs. This article reports the results of a small workshop convened to discuss this topic. It is argued that the maximum science return for the Hera samples would be obtained if asteroids of different major spectral classes were visited, samples were disturbed as little as possible during collection, and samples from the very surface were obtained. Surface samples would have the utmost value in interpreting links between asteroids and meteorites, would yield maximum information in solar exposure, would avoid planetary protection concerns, and would produce material not reaching Earth as meteorites. At the same time, they would be simpler to sample than subsurface samples. � 2004 COSPAR. Published by Elsevier Ltd. All rights reserved.