NEW YORK - Nasa is to allow tourists to visit the International Space Station from 2020. The US space agency said it would open the orbiting station to tourism and other business ventures.

There will be up to two short private astronaut missions per year, said Robyn Gatens, the deputy director of the ISS. The first component of the ISS was launched into orbit in 1998, and the station has been continually occupied since November 2011. “Nasa is opening the International Space Station to commercial opportunities and marketing these opportunities as we’ve never done before,” chief financial officer Jeff DeWit said in New York. Nasa announced that private astronauts would be permitted to travel to the ISS for up to 30 days. The tourists would travel on US spacecraft.

It said that a private commercial entity would be charged with determining crew composition and ensuring that the private astronauts meet the medical and training requirements for spaceflight.