Every single day, humans rely on hundreds of hidden clocks.
GPS location, Internet stability, stock trading, power grid management ... all rely on atomic clocks in order to work. Many of those clocks are in orbit, perched on satellites orbiting Earth.
Over time, temperatures swings, power supply and the speed at which the clock is moving can set these clocks very slightly out of sync. This phenomenon is called "clock drift." To control for it, GPS clocks are set to check the time and correct themselves regularly.
But in outer space, critical functions like communication and navigation require even greater clock accuracy, down to a billionth of a second — or more. That's why atomic physicists at NASA want to build a more precise, more autonomous atomic clock.
The team hopes a prototype will be ready by late 2025.
For more about Holly's Optical Atomic Strontium Ion Clock, check out the OASIC project on NASA's website.
For more about the Longitude Problem, check out Dava Sobel's book, Longitude.
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This episode was produced by Hannah Chinn. It was edited by our showrunner, Rebecca Ramirez. Tyler Jones checked the facts. Jimmy Keeley was the audio engineer.
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