Enlarge / The crew of Polaris Dawn, from L to R: Scott “Kidd” Poteet, Anna Menon, Sarah Gillis, and Jared Isaacman. (credit: Polaris Program/John Kraus)

SpaceX is set to launch the 14th crewed flight on its Dragon spacecraft early on Tuesday morning—and it’s an intriguing one.

This Polaris Dawn mission, helmed and funded by an entrepreneur and billionaire named Jared Isaacman, is scheduled to lift off at 3:38 am ET (07:38 UTC) on Tuesday from Launch Complex 39A at Kennedy Space Center in Florida.

This is just the second free-flying Crew Dragon mission that SpaceX has flown, and like the Inspiration4 mission that came before it, Polaris Dawn will once again field an entire crew of private astronauts. Although this is a private spaceflight, it really is not a space tourism mission. Rather, it seeks to push the ball of exploration forward. Isaacman has emerged as one of the most serious figures in commercial spaceflight in recent years, spending hundreds of millions of dollars to fly into space and push forward the boundaries of what private citizens can do in space.