Former NASA astronaut Michael López-Alegra is about to take three paying passengers into orbit - but they aren't "space tourists," the veteran spaceflyer emphasizes.

That's according to Michael Lopez-Alegria, a former NASA astronaut who is now the commander of the Ax-1 mission, which will launch from Kennedy Space Center on Mar. 30 aboard a SpaceX Dragon and spend eight days in orbit.

López-Alegra will command Axiom Space's private Ax-1 mission to the International Space Station, which is set to launch from NASA's Kennedy Space Center in Florida on Friday (Apr. 8).

The astronauts will travel in a SpaceX Dragon capsule, which will launch atop a Falcon 9 rocket. López-Alegra is being compensated for this 10-day mission, but his three crewmates are likely to have paid about $55 million each for the experience.

"I believe there is a role for space tourism, but it is not what Axiom is about," Lopez-Alegria said. "My crewmates have worked very hard. They're busy people who have taken a lot of time out of their lives to focus on this, and it's definitely not a vacation for them."

The astronauts will travel in a SpaceX Dragon capsule that will be launched atop a Falcon 9 rocket. Although López-Alegra is being compensated for his 10-day mission, his three crewmates are likely to have paid around $55 million each for the experience.

The voyages are viewed by Axiom as the first steps toward a larger goal: the construction of its own private space station. According to president and CEO Michael Suffredini, the first module will be available in September 2024.

It will initially be attached to the International Space Station (ISS), but will eventually fly independently once the latter retires and is deorbited after 2030.

NASA wants to commercialize so-called Low Earth Orbit, allowing the private sector to manage space stations for research and business while NASA concentrates on exploration missions to the Moon and Mars.

The crew, which includes commander López-Alegra, pilot Connor, and mission specialists Eytan Stibbe and Mark Pathy, began training over a year ahead of the flight, according to Ax-1 mission pilot Larry Connor, a real estate entrepreneur.

While no comparison is necessary, NASA astronauts must meet minimum requirements, which include a master's degree in a STEM (science, technology, engineering, and mathematics) field and at least two years of relevant experience. According to NASA, they can train for up to two years to become a "fully qualified astronaut" before their first flight.