Question

3. What is the relationship between longitude and time?
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Answer 1

Explanation:

Local time is the time at one particular meridian. Since the sun cannot transit two meridians simultaneously, no two meridians have exactly the same local time. The difference in time between two meridians is the time of the sun's passage from one meridian to the other.

Answer 2

Answer:

Longitude lines, as we have agreed to mark and measure them, exist in the same plane as the axis around which the earth spins. Picture the earth as a tangerine. If you peel the tangerine and pull it in half (doing your best to keep the sections intact), the axis is where all the segments come together in the middle, and the circumference of the tangerine is a single line of longitude. If the half-tangerine-earth is revolving around a cantaloupe sun (model not to scale), the cantaloupe will rise on one side of the tangerine axis, then on the other side of the tangerine axis twelve hours later.

Now, before we had computers, cell phones, Global Positioning System (GPS) satellites and receivers, latitude was easy to figure out using the angles of stars (once you got used to the fact that the deck of the ship was always moving in not-entirely-predictable ways). Longitude was much more difficult to figure out at sea, since the same stars and other heavenly bodies appear above all longitude lines, just at different *times*.