Garver’s proposed change would widen the number of target asteroids and would test technologies important for asteroid mining. But it would also increase the complexity and certainly the cost of the asteroid mission. There are a lot of unanswered questions, such as what kind of mechanism would be involved in taking a piece of an asteroid and moving it?
At the same conference Garver had hinted at a willingness to consider mounting a program of "sustainable" lunar exploration, as some in Congress have demanded, concurrent with the asteroid mission."
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