Neil deGrasse Tyson is willing to fly to Mars with SpaceX, as long as company founder and CEO Elon Musk meets a few key conditions.

“I really like Earth. So any space trip I take, I’m double-checking that there’s sufficient funds for me to return,” Tyson wrote during a Reddit “Ask Me Anything” (AMA) session on Sunday (April 2).”Also, I’m not taking that trip until Elon Musk send[s] his mother and brings her back alive. Then I’m good for it.”

Tyson was responding to a question about SpaceX’s historic launch last week, during which a used Falcon 9 rocket first stage helped send the SES-10 communications satellite to orbit. The questioner also asked if Tyson would ever consider going on a one-way Mars trip.

SpaceX aims to help colonize Mars, and the company regards the development of fully and rapidly reusable rockets as central to that goal. Such technology could spur a spaceflight revolution by slashing launch costs, Musk has said.

Tyson said he’s a fan of the company’s focus on reusable boosters.

“Any demonstration of rocket reusability is a good thing,” the astrophysicist and science communicator  wrote in the AMA. “When we fly on a Boeing 747 across great distances, we don’t throw it away and roll out a new one. Reusability is arguably the most fundamental feature of affordable expensive things.”

Seen on Space.com