NASA wants to return to the Moon, but it would like to do so in a way different from the Apollo Program—more sustainably, so that there are not just a handful of missions before humans retreat back into low-Earth orbit.

As part of this, NASA Administrator Jim Bridenstine has said he prefers the space agency to be one of several customers for private companies interested in building transportation systems to the lunar surface and back. Initially, of course, NASA would be the sole customer, but over time, the agency would like to foster the commercial development of the Moon.

Because aerospace companies may one day find additional customers for their services, NASA has asked companies to invest in the rockets, landers, and spacecraft they are building as part of the agency’s Artemis Moon program. In short, NASA wants its contractors to put some skin in the game.