Keith's note: JSC is webcasting part of their media event with some of the cast of The Martian (it was a last minute decision for JSC to put this on NASA TV BTW). In the movie there is artificial gravity on the ship that goes to/from Mars. The new ISS Program Manager Kirk Shireman spent a lot of time describing what the 2.5 meter Centrifuge Facility could/might provide in terms of supporting human missions to Mars. But Shireman neglected to mention that NASA traded the development of the Centrifuge Facility and Module in one of its bait and switch moves to Japan to offset some ISS costs and then eventually cancelled it outright in 2005. But NASA JSC clearly doesn't want movie goers to know that NASA did dumb stuff like this.
Funny thing: back in the day (early 1990s) I was Payload Accommodations Manager for that the Space Station Freedom Program Office for the CF and CAM - and JSC fought that thing tooth and nail. Now they love it. Go figure.