Space travel is a very exclusive club, with just over 500 people in world history having been granted the opportunity to free themselves from Earth’s confines. If and when billionaire Richard Branson’s Virgin Galactic adds to the number, Stephen Hawking will be on the passenger list.

In an interview with Good Morning Britain, the 75-year-old physicist said that Branson has invited him on the space company’s maiden voyage and that he has accepted.

“Richard Branson has offered me a seat on Virgin Galactic, and I said yes immediately,” he said. “I can tell you what will make me happy—to travel in space.”

Branson’s Virgin Galactic was conceived in 2004 as a way of commercial industry supplementing government-funded programs like NASA and allowing for private citizens to take sub-orbital flights. Branson originally promised the first flight would happen in 2007, but years of delays have pushed the date back. In 2014, co-pilot Michael Alsbury was killed during a test flight.

Branson is still actively working toward a start date within the next few years that would see passengers pay up to $250,000 a ticket in order to experience zero gravity. For the first official flight, Branson expects to be on board with family members—and, presumably, Hawking, although it’s unknown what kind of medical clearance Virgin Galactic needs or whether Hawking’s age or amyotrophic lateral sclerosis (ALS) affliction would prove to be obstacles.

[h/t Independent]