Science Agenda: To the Moons, NASA; July 2012; Scientific
American Magazine; by The Editors; 1 Page(s) Last year, after a
lengthy, circuitous journey through the solar system, a NASA
probe known as MESSENGER entered into orbit around Mercury. No
spacecraft had visited the innermost planet in more than three
decades, and none has paid an extended visit. With MESSENGER's
arrival, NASA and its international counterparts now have
spacecraft stationed at Mercury, Venus, Mars and Saturn—not to
mention Earth and the moon. Two more NASA craft are en route to
Jupiter and Pluto; yet another ought to reach the dwarf planet
Ceres in 2015. Humankind's presence has never stretched so far.
It could stretch farther still, with robots spying down on
bizarre moons that might harbor alien life or on the little-
understood outermost planets. An even more novel campaign would
ferry Martian rocks back to Earth for analysis. NASA had been on
track to begin such an ambitious project, but alas, political
maneuvering recently forced th