At one time under consideration by NASA and the Air Force, atom bomb powered super ships over 20,000 tons could have put a crew of 150 men on Mars by 1970 and at the same cost as the Apollo program. And it's Von Braun approved.
http://www.astronautix.com/articles/probirth.htm
The original Orion project: Nuclear-powered flights to Mars
Moderator: Vincent
The original Orion project: Nuclear-powered flights to Mars
4-time Space Camp/Academy alumni
1989, 1991*, 1992, 1994
*Right Stuff Award Winner
1989, 1991*, 1992, 1994
*Right Stuff Award Winner