A United States billionaire who made a fortune in tech and fighter jets is buying an entire SpaceX flight and plans to take three people with him to circle the globe this year.

Besides fulfilling his dream of flying in space, Jared Isaacman announced Monday that he aimed to use the private trip to raise $200m for St Jude Children’s Research Hospital, half coming from his own pockets.

A healthcare worker for St Jude already has been selected for the mission. Anyone donating to St Jude in February will be entered into a random drawing for seat number three. The fourth seat will go to a business owner who uses Shift4 Payments, Isaacman’s credit card processing company in Allentown, Pennsylvania.

“I truly want us to live in a world 50 or 100 years from now where people are jumping in their rockets like the Jetsons and there are families bouncing around on the moon with their kid in a spacesuit,” Isaacman, who turns 38 next week, told The Associated Press.

“I also think if we are going to live in that world, we better conquer childhood cancer along the way.”

He’s bought a Super Bowl advertisement to publicise the mission, dubbed Inspiration4 and targeted for October. Details of the ride in a SpaceX Dragon capsule are still being worked out, including the number of days the four will be in orbit after blasting off from Florida. The other passengers will be announced next month.

Isaacman’s trip is the latest private space travel announcement. Three businessmen are paying $55m apiece to fly to the International Space Station next January on board a SpaceX Dragon. And a Japanese businessman has a deal with SpaceX to fly to the moon in a few years.

Isaacman would not divulge how much he is paying SpaceX, except to say that the anticipated donation to St Jude “vastly exceeds the cost of the mission”.

While a former NASA astronaut will accompany the three businessmen, Isaacman will serve as his own spacecraft commander. The appeal, he said, is learning all about SpaceX’s Dragon and Falcon 9 rocket. While the capsules are designed to fly autonomously, a pilot can override the system in an emergency.

A “space geek” since kindergarten, Isaacman dropped out of high school when he was 16, got a GED certificate and started a business in his parents’ basement that became the genesis for Shift4. He set a speed record flying around the world in 2009 while raising money for the Make-A-Wish programme, and later established Draken International, the world’s largest private fleet of fighter jets.

Isaacman’s $100m commitment to St Jude in Memphis, Tennessee is the largest ever by a single individual and one of the largest overall.

“We’re pinching ourselves every single day,” said Rick Shadyac, president of St Jude’s fundraising organisation.

Besides SpaceX training, Isaacman intends to take his crew on a mountain expedition to mimic his most uncomfortable experience so far — tenting on the side of a mountain in bitter winter conditions.

“We’re all going to get to know each other … really well before launch,” he said.

He is acutely aware of the need for things to go well.

“If something does go wrong, it will set back every other person’s ambition to go and become a commercial astronaut,” he said from his home in Easton, Pennsylvania.

Isaacman said he signed with Elon Musk’s company because it is the clear leader in commercial spaceflight, with two astronaut flights already completed. Boeing has yet to fly astronauts to the space station for NASA. While Richard Branson’s Virgin Galactic and Jeff Bezos’ Blue Origin expect to start flying customers later this year, their craft will just briefly skim the surface of space.

Isaacman had put out spaceflight feelers for years. He travelled to Kazakhstan in 2008 to see a Russian Soyuz blast off with a tourist on board, then a few years later attended one of NASA’s last space shuttle launches. SpaceX invited him to the company’s second astronaut launch for NASA in November.

While Isaacman and wife, Monica, managed to keep his space trip hush-hush for the months, their daughters could not. The girls, ages seven and four, overheard their parents discussing the flight last year and told their teachers, who called to ask if it was true dad was an astronaut.

“My wife said, ‘No, of course not, you know how these kids make things up.’ But I mean the reality is my kids weren’t that far off with that one,” Isaacman said.