Shuttle Science Missions: Just Along for the Ride? further pushes the point that we don’t really need astronauts:
From studies of protein crystallization to the behavior of fire in zero gravity, “there is no experiment that has been done on the space shuttle that has made a significant difference to any field of science,” says physicist Robert Park of the American Physical Society in College Park, Md.
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“The results of shuttle experiments and space experiments are not published in refereed scientific journals” very often, says Alex Roland, professor of military history and the history of technology at Duke University in Durham, N.C. “NASA often has to publish the results itself because they’re not cutting edge science, by and large. There’s a lot of make-work going on up there.”