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You're listening to Short Wave from npr.
Hey, everyone.
Regina Barber here with Emily Kwong.
And a story about time.
Yes, a tale about how time tells us our place in the world.
So, Gina, are you familiar with longitude?
Yeah.
So longitude is like the east west position on Earth.
It's relative to the prime meridian in Greenwich, England, right?
Yeah.
The longitude there is 0 degrees and extends by 180 degrees westward and 180 degrees eastward.
And back in the 1600s, it was really difficult to calculate longitude.
A ship leaving port would set two clocks, one for the prime meridian and another for local time.
So crews would update their local time as they sailed, calculating it by using the position of the sun and by.
Knowing the difference between these two times, you can calculate, like, the in between longitudinal degrees and know your location.
Yeah, you can math.