Whether you're relying on the careful observations of 1950s amateur astronomers and backyard telescopes or state-of-the-art GPS tracking and navigation technology: knowing where you are in space means needing to know what time it is.

https://www.nasa.gov/mediacast/goddard/2018/the-invisible-network-podcast-episode-03-time

The Invisible Network: Episode 03 - Time

Hello, we’re NASA. You may have seen our astronauts, rocket launches, or Mars rovers — but have you heard our sounds? From interviews with astronauts and engineers to stories that take you on a tour of the galaxy, NASA’s audio offerings let you experience the thrill of space exploration without ever leaving Earth.