The companies have been developing their own spacecraft, which will also be used for government-backed ISS launches and private space trips.
However, as it turns out, NASA will also have a role in private missions.
NASA's plan to allow short-term trips to space station
Once SpaceX's Crew Dragon and Boeing's Starliner spacecraft are tested and ready for human spaceflight, NASA will use them to regularly fly astronauts to the ISS and back for 6-7-month-long stays.
Further, the agency is also planning the commercialization of the station, which would allow both these 'space taxi operators' to conduct two more short-term private missions every year.
Private missions would cost multi-million dollars
As part of the private missions, the companies would fly paying tourists to the station for a maximum 30-day-long stay.
They would charge a multi-million dollar fee for taking them up to the station, post which NASA will charge about $35,000/day for boarding and lodging on the ISS.
Finally, after the stay is complete, the craft would be used to bring them back.
NASA wants to book a seat in private missions too
Just recently, NASA announced that along with the regular flights to the ISS, it also plans to book a seat in the short-term privatized missions.
The agency issued a pre-solicitation notice confirming the intention to buy a seat in the private missions, asserting that the move will help with furthering its research goals for manned missions to Moon, Mars, and beyond.
This will help NASA keep astronauts healthy in deep space
NASA explained that the data collected from varying lengths of flight, including regular and short-term trips, will help them establish profiles of human physiological, behavioral, and psychological variables of importance.
This will ultimately help them ensure that astronauts headed on planned deep-space missions to Moon and Mars remain healthy and high-functioning throughout their time in space.
When short tourist trips will be conducted?
Meanwhile, the short tourist trips will be conducted when both Boeing and SpaceX will complete all the crewed and uncrewed tests of their spacecraft and receive NASA's certification.
According to the current plan, both companies should have their spacecraft ready to take NASA astronauts to the ISS sometime next year.
Then, perhaps a year later, they might schedule the extra private missions.