Why buy an around-the-world ticket when a few million dollars will take you to the moon? Entrepreneurs are banking on space as the next wave in travel. With the expectation that it will amount to billions of dollars in revenue, companies like Virgin, with its prototype space plane Virgin Galactic, are leading the way in private space travel. Space Adventures is developing what it hopes will be the first private lunar expedition. They anticipate ferrying thousands of travelers to the moon and eventually beyond. Hotel chains, such as Hilton Hotels, are looking into the feasibility of providing travelers with accommodations on the moon that feature all the comforts of home.

The moon has no atmosphere, but it does have an environment, however rocky and dusty it may be. Preservation is at the top of the list for some developers. Hans-Jurgen Rombaut, of the Rotterdam Academy of Architecture, is thinking of ways to keep travelers safe and minimize the impact of visitors to the moon. One idea is to restrict access to certain zones as a way to stave off "footprint pollution."