We are facing some huge problems in the world and right here in the United States. They include: health, education, oil, crime, and highway infrastructure to name a few.
I agree that looking toward goals that stretch our imaginations and make us feel better about a brighter future raises the human spirit. But, when I think of the money spent on space missions and the attempt to land men on Mars, I can't help but think that there are students who can't afford to go to college. There are elderly folk who have to choose between eating and medication or worse.
How 'bout setting goals like these: find a cure for cancer, cover human beings need for health care, provide the best possible education for everyone, find a better source of cheaper energy and other goals in these areas.