The space elevator has been a staple of science fiction for decades, from The Fountains of Paradise by Arthur C. Clarke to the Apple TV show “Foundation.” But the work and theories to make it a reality have been in development since the late 19th century.It’s a simple concept: Imagine a long cable, stretching from the Earth’s surface to a satellite locked in orbit 22,000 miles high. It would work like elevators here on Earth, enabling us to send things—and people—up into space. And it would make the need for the expensive rockets we use today obsolete.Although it has never been considered feasible due to the exorbitant cost and the engineering challenges it poses, the idea refuses to go away.One of Japan’s biggest construction companies, the Obayashi Corporation, which built the Tokyo Sky Tree, had plans to build a space elevator in 2025 but has reportedly delayed that goal.So what are the hurdles that keep us from building it? And why does it seem that the space elevator is always 25 years away? Ira Flatow is joined by Dr. Dennis Wright, president of the International Space Elevator Consortium to talk about the feasibility of this megaproject.Transcripts for each segment will be available after the show airs on sciencefriday.com. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.