With all of the attention on the 50th anniversary of the Lunar landing, many are looking ahead to the next half century of space exploration. Of particular interest is returning to the Moon which may come as early as 2024.

For example, Boeing is working on the replacement for the Saturn 5 rocket which lifted the Apollo space capsules into orbit. The centerpiece of NASA’s Space Launch System (SLS) is the heavy-lift rocket being built to safely carry people and cargo back to the Moon and hopefully, on to Mars.

One of the leading proponents of returning to the Moon is American astronaut Ha...