The world got to witness billionaires in (or on the edge of) space over the last few weeks as both Richard Branson took a ride on one of his Virgin Galactic rocket ships and Jeff Bezos, now the ex-CEO of Amazon, followed in his Blue Origin vehicle. Meanwhile, Tesla’s Elon Musk also has been developing space travel vehicles through his company SpaceX.

What’s fueling these billionaires’ race to space?

“They have the amount of capital that governments dream to have,” says Mehak Sarang, the Lunar Explorations Projects Lead at MIT Media Lab’s Space Exploration Initiative and a research associate at Harvard Business School. “And I think there is one part of it that’s just like, what do we do with this money? Let me do something cool. Let’s go to space. I think people are always like, ‘what’s the business case for space?'”

Sarang joins Michal Lev-Ram and Brian O’Keefe, the hosts of the Fortune Brainstorm podcast, to discuss the billionaires’ space race. Each episode of the podcast explores how technology is reshaping our world.

Also on the show is Christian Maender, director of in-space manufacturing and research for Axiom Space. His company plans to build the first private space station, beginning in 2024. That station will enable new efforts in space once the International Space Station is decommissioned.

Maender says that the weightlessness that a microgravity environment provides will allow researchers to look at the way “fundamental forces behave differently” and “potentially [allow humans to] manufacture or research things in a different way.”

Rounding out the show is Peter M. Hughes, center chief technologist for NASA’s Goddard Space Flight Center. “This is an exciting time,” Hughes says, “because NASA has kind of helped tee up these [commercial] capabilities and made investments in that. So we can continue our mission to explore the Earth from the vantage point of space, explore the nearby planetary systems, and understand what’s going on deeper in space—in addition to exploring our nearest, you know, planetary body, the moon, and put the first woman and then next man on the lunar surface by 2023.”