NASA is planning to allow private astronauts to fly to the International Space Station, as well as open up the orbiting laboratory to more commercial interests, including filming advertisements in an attempt to help fund its crash plan to return astronauts to the moon by 2024, the agency announced Friday.

The announcement is a significant change for the agency, which has had a long-standing prohibition against allowing tourists and commercial interests on the station, which has cost taxpayers about $100 billion over its lifespan. Russia, however, has allowed several private astronauts on the station.

Under the NASA plan, as many as two private astronauts per year could fly to the station and stay for up to 30 days with the first mission coming as early as next year.

Jeff DeWit, NASA’s chief financial officer, estimate that the cost per trip would be about $50 million a seat. But the cost and arrangements would be left to SpaceX and Boeing, the two companies NASA has hired to fly crews to the station. While on board the station, NASA would charge people for food, storage and communication, a cost that would come to about $35,000 a night.

“But it won’t come with any Hilton or Marriott points,” DeWit said.

Right now, commercial activity on the station is largely limited to science experiments. But under the new policy, NASA would allow business to pursue profit by allowing them a range of pursuits, including marketing and advertising.

“We have no idea what kinds of creativity and literally out of the world ideas can come from private industry,” Bill Gerstenmaier, NASA’s head of human exploration, said during a news conference.

The goal is to help the agency generate additional revenue. But officials said it was unclear how much money the efforts would produce.

“It’s hard to project what’s going to come back,” DeWit said. “What we’re hearing is is a lot of excitement in the commercial sector for this. But it’s hard to get accurate projections until six or 12 months from now, when we see what actually comes back in and who partners with us.”

The announcement comes as the agency is trying to return humans to the moon by 2024, a crash mission that officials said would require significant additional funding.

NASA has already amended its budget request for next year to ask for an addition $1.6 billion, and has said that it would need significantly more money in the years to come to have any chance at pulling off such an ambitious plan.