sentences:  According to Easterbrook, the billions of dollars that a lunar colony might cost should instead be devoted to exploring the Solar System with space probes; space observatories; and protecting the Earth from near-Earth asteroids.Buzz Aldrin, the second of twelve men to have walked on the Moon, disagrees with NASA's current goals and priorities, including their plans for a lunar outpost.While not necessarily opposed to sending people back to the Moon, Aldrin argues that NASA should concentrate on a crewed mission to Mars and leave further lunar exploration and the establishment of a base there to a consortium of other countries under U.S. leadership.