... built by the U.S. Naval Research Laboratory, are being deployed by NASA from Hitchhiker canisters in Space Shuttle cargo bays, as well as from an Athena unmanned launch vehicle, into highly inclined low earthorbits at a rate of once every year or so ...
... To carry 33 men into orbits around different planets, land all of them , if necessary and some 320 pounds of scientific equipment on the different planets surface, and then return the crew safely to the earth . ...