I was probably too terse. Those missions are above some level of complexity. Robots - even today's ones - scale rather poorly with the complexity required, whil

I was probably too terse. Those missions are above some level of complexity. Robots - even today's ones - scale rather poorly with the complexity required, while for humans a lot of what's needed comes "for free". So, if you need a large expedition to the Moon, which explores places and various aspects, human crews can possibly return results faster and cheaper than similar results could be returned by space robots. > A lot of the manned space stuff - even a lot of the unmanned space stuff - is someone deciding that we need to use a hammer to make something, and therefore making nails part of every plan they have. Used to be more, now it's less and less, with decisions being less centralized. In USSR space science initially was discussed on the level of national academy, the highest existing. Now a small group of students can invent a mission to study a particular aspect and get to results.