NASA said Friday it will open up the International Space Station to business ventures including space tourism — with stays priced at $35,000 a night — as it seeks to financially disengage from the orbiting research lab.

"NASA is opening the International Space Station to commercial opportunities and marketing these opportunities as we've never done before," NASA chief financial officer Jeff DeWit said in New York.

There will be up to two short private astronaut missions per year, said Robyn Gatens, deputy director of the ISS.

The missions will be for stays of up to 30 days. As many as a dozen private astronauts could visit the ISS per year, NASA said.

These travelers would be ferried to the orbiter exclusively by the two companies currently developing transport vehicles for NASA: SpaceX, with its Crew Dragon capsule, and Boeing, which is building one called Starliner.

These companies would choose the clients and bill for the trip to the ISS, which will be the most expensive part of the adventure: around $58 million for a round trip ticket.

That is the average rate the companies will bill NASA for taking the space adventurers up to the ISS.

But the tourists will also pay NASA for their stay in space, for food, water and use of the life support system on the orbiter.

That will run about $35,000 per night per astronaut, said DeWit.

The space station does not belong to NASA. It was built along with Russia starting in 1998, and other countries participate in the mission and send up astronauts.

But the U.S. has paid for and controls most of the modules that make up the orbiter.

The new space tourists to the ISS will not be the first: U.S. businessman Dennis Tito had that honor in 2001. He paid Russia around $20 million for the trip.