Space: Men for Moon & Mars

Seven years ago this month, the first seven U.S. astronauts were introduced with fanfare at a Washington press conference. Last week, by contrast, when the National Aeronautics and Space Administration announced its fifth and largest group of spacemen, the 19 appointees were not around to take a bow. If their selection had lost some of its novelty value, their credentials were just as distinguished as those of their predecessors—and their missions would be even farther out.

Class No. 5—bringing to 50 the total roster of active astronauts—is younger and better educated than the original Mercury team (32.8 years v. 34.5;...