Could the United States establish a moon colony and develop a new propulsion system for going to Mars? All within eight years of a Newt Gingrich presidency, as Mr. Gingrich promised this week?

The answers seem to be technologically yes, economically iffy and politically very difficult.

In proposing an ambitious vision for space, Mr. Gingrich stepped into the eternal debate over where the nation’s and NASA’s priorities should lie. Mr. Gingrich spoke little about NASA’s unmanned missions, which many think produce better science with less money. Inspiration and economic frontiers, not science, drive his long-standing enthusiasm for space.

“I come at space from a standpoint of a romantic belief that it really is part of our destiny,” Mr. Gingrich said in his speech on Wednesday. He joked about a legislative proposal, early in his Congressional career, that a moon colony could apply for statehood once its population reached 13,000.

Not surprisingly, at a debate on Thursday, Mr. Gingrich’s Republican opponents lambasted a moon colony as a loony, budget-busting idea in a time of fiscal austerity.