For the moon, I was under the impression we were returning to the moon in 2018. But either way, it will be roughly 50 years from Apollo when we finally land. The exploration of Antarctica is a close analogy. We first went sometime in the 1800s IIRC. Then didn't go back for decades before finally going back and making it slowly a more permanent outpost.<br /><br />As for Mars, Under the present plan, I think they would be looking at being on Mars 10-15 years after the initial lunar mission. The timeline gives NASA the necessary experience with operating the vehicle systems and if the lunar base becomes a base. Operating a base on the moon will be beneficial to a base on Mars. Using chemical or NTR to Mars will result in approximately 30 day stays as this is due to the planetary alignments. In the long transit scenario (Conjunction class or opposition class mission, can't recall which), the stay times are 30 days. In the shorter transit scenarios, the stay times can be two years because of the requirement to wait for planetary alignments to favor return trajectories.<br /><br />The pace of change you describe is possible, but the more likely scenario is change itself. Change brings variables we don't see at the beginning. The big variable here is...How much will private enterprise be involved?<br /><br />ISS is an example of being in the model-T phase of permanent space occupancy. What we learn from ISS and future efforts will move us further forward at a more accellerated pace.<br /><br />I would agree that full blown human colonies may take some time to come about. Think of it this way. Imagine what a futurist in 1776 might have though we'd be like in 2006 and how much would he/she actually get right if they could see what actually came about.<br /><br />Another is the era I came up in. In 1968, fresh from the movie "2001, A Space Odyssey" and Apollo 11. Hardly anyone imagined we'd be as "Throttled back" as we are now. It seems that whenever we try to predict something, we ge <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>