NEW YORK (AP) — NASA announced Friday that it will open the International Space Station to private astronauts, with the first visit as early as next year.

The round-trip ticket will cost an estimated $58 million. And accommodations aboard the orbiting outpost will run about $35,000 per night, for trips of up to 30 days long.

The space agency says only two visitors per year will be allowed, for now. Private astronauts will have to meet the same medical standards and training and certification procedures as regular crew members.