Time Equals Longitude
Since the Earth rotates at a steady rate of 360° per day, or 15° per hour (in mean solar time), there is a direct relationship between time and longitude. If the navigator knew the time at a fixed reference point when some event occurred at the ship's location, the difference between the reference time and the apparent local time would give the ship's position relative to the fixed location. Finding apparent local time is relatively easy. The problem, ultimately, was how to determine the time at a distant reference point while on a ship.
Read more about this topic: History Of Longitude
Famous quotes containing the words time and/or equals:
“Life’s so short, Katie. You have to make every moment count. It’s not easy to do, you know. I don’t think that a day goes by when I don’t turn my back on some small thing or some issue somewhere. But it’s so short, Katie. If you’re not careful, the days go by and all you have time for is regret.”
—Blake Edwards (b. 1922)
“My anger thought you too ignoble for my love, and close examination finds you too magnificent, and only equals are joined together smoothly.”
—Franz Grillparzer (1791–1872)