The big picture: Space tourism is quickly developing into a favorite pastime for the few who can afford it. While it might sound like a pipe dream right now, these early flights could pave the way to lowering costs and allow ordinary people to experience it someday.

Axiom Space, together with SpaceX, successfully launched their first private crew mission on Friday. The four astronauts launched from the Kennedy Space Center in Florida on SpaceX’s Falcon 9 rocket. They will arrive at the ISS tomorrow, making this the first all-private human spaceflight mission to the station.

The crew consists of Spanish-American Michael López-Alegría, former NASA astronaut and flight commander; American Larry Connor, founder of real estate investment firm Connor Group; Israeli Eytan Stibbe, former fighter pilot and founder of investment fund Vital Capital; and Canadian Mark Pathy, CEO of investment and financing company Mavrik.

The private astronauts spent hundreds of hours training for this mission, learning basic protocols like using the food galley and practicing personal hygiene in microgravity. They have also received emergency response training in case something goes wrong aboard the ISS.

The crew will be staying for eight days on the US segment of the ISS, where they will be conducting more than 25 different research experiments. They have also been invited to visit the Russian portion of the station by the three cosmonauts on board.

Afterward, they will depart on the same Crew Dragon spacecraft currently taking them to the ISS and land in the Atlantic Ocean. This whole trip cost the three private astronauts a staggering $55 million each.

Following their first flight, Axiom plans to offer similar crewed flights as often as twice per year. They are also aiming to launch modules into space that would attach to the ISS and allow private astronauts to inhabit them.