|Courtesy of Star Trek: Enterprise. A Mars Memorial|
the solar system they will begin to visit the historical landing sites of Apollo, Luna II, and Curiosity. But who will protect these sites from overambitious souvenir hunters? That is a big question and an opportunity for the future space industry.
Organizations/Companies can and need to be created in order to protect and preserve these sites that are a part of human history. The opportunity comes from either being contracted by governments to "defend" them from vandalism or by turning them into "pay to enter" museums. But the combination of the two will be the most likely. Governments wanting to preserve the artifacts will subsidize any company with the technology to do so. Then the company will be able to charge admission to the the site which they have been given protective custody over.
What would be needed to create these museums? Not a lot. On the Moon a simple fence could be erected around the Apollo modules and basically patrolled by robots. Visitors would be able to work through an automatic system in order to gain access and would be given a tour, probably along a special visitor path to prevent footprints, by a telepresence robot controlled from Earth. The admission fees would be on the order of several thousand dollars in the early days and would come down as lunar travel became more common. All of this would be able to be constructed with rovers, but if lunar tourism is common it would most likely be easier to simply send a human crew to create the site.
On Mars it will be very different. Historical sites will need to be protected from the environment as well as the visitors and there is no chance of telepresence due to radio lag. Each site would need to have a structure built around it, most likely some type of inflatable dome. Or perhaps a solid display case, of sorts, could be created that allows guests to look inside to see the landers but not touch or vandalize them. Another option, since there is no need to preserve footprints on Mars and there are no significantly large structures, a museum could be created and then each of the artifacts would be collected and put on display as in a normal museum on earth. Again government subsidies would play a large role and then the museum would be able to become one of the "attractions" of a Martian vacation.
But there is no reason to leave all of these artifacts on the Moon or Mars. A time will come when some artifacts may be brought back to their home planet just as pottery is brought from an archaeological dig. Sojourner would be something akin to a famous painting. And the organization that has custody of it will be the one to profit from its transport.
While the first few hundred humans will no doubt be very respectful of the pieces of history that are scattered around the solar system, preservation is an issue that will need to be addressed as space travel and tourism begin to become common. The footprints on the Moon are irreplaceable like the Mona Lisa. An opportunity exists today for space entrepreneurs to create a framework to protect these artifacts and become the curators and owners of the first interplanetary museums.