"Nuclear-propelled rockets should only be used well away from the Earth, " says Charles Oman, a senior research engineer at MIT's department of Aeronautics and Astronautics.

FORBES: Houston, We Have Problems

"The rates of return just aren't there, and it could take another 100 years before they are, " says Charles Oman, a senior research engineer at MIT's Department of Aeronautics and Astronautics.

FORBES: Galactic Gold Mine?