I wrote:
What really makes a huge difference, though, is if the people are actually
landing on moons etc. themselves, rather than just by robotic proxies.
Having hands as well as brains on the scene is a vast improvement when it
comes to exploring planetary surfaces. Even the more optimistic robotics
researchers say it will be half a century before a robot can climb down a
geothermal vent, something a human explorer can do today.

A corollary to this is that you do not make the manned expedition more
competitive with robots by shrinking it and cutting back its objectives to
reduce its cost. The manned expedition looks better as the crew gets
larger, the stay gets longer, and the objectives get more ambitious.
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |