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Name: Sonya D.
Status: other
Grade: other
Location: NV
Country: N/A
Date: N/A

If I were to chase the sun, so as to live through the longest Wednesday possible, where would I have to start, to extend the hours available, and how many countries/time zones would I pass through before I eventually reached Thursday? If I headed for one of the Poles, would that give me the most time, and what would I be measuring, if not conventional time on a clock?

Dear Sonya,

No matter how far north you go, the day is still 24 hours long. At the pole, in summer, the sun never sets, but time still marches along like anywhere else.

David H. Levy

Dear Sonya,

If you fly west, as you cross time zones, you will gain clock time due to time zones.

Nathan A. Unterman


I think you can think through all of these questions yourself if you think of a ball spinning on its axis in the light of a lamp. Here are the facts you need to know to answer the questions.

New days start at the International Dateline at 180 degrees longitude which is near the middle of the Pacific ocean. It runs West of Hawaii and East of New Zealand. So for the longest Wednesday you would start at the International Dateline at Sunrise.

The circumference of the earth at the equator is approximately 25,000 miles, so 25,000 miles divided by 24 hours gives an approximate speed of 1000 miles per hour.

But at the poles, you could reach a point where you would need to travel 0 miles in 24 hours. Let us say you stepped one foot away from the pole, then it would take you 24 hours of Wednesday to rotate around the pole but you would be in constant daylight a couple of weeks before and after the Summer Solstice (June 21) at the North Pole, and the Winter Solstice (December 21) at the South Pole.

The number of time zones can be found at: Which says: "There are currently 40 world time zones. There are 24 standard time zones plus up to 16 (or maybe more) areas of the world that that use time zones divided into 15-30-45 minute increments. China, about the size of the United States, uses the same time throughout the country even though it crosses 4 standard time zones."

How many countries? That depends on the Latitude at which you are travelling.

You would reach Thursday at midnight at the International Dateline.

What time would you be measuring if not regular time on a clock? You can pick any time standard you wish: Heart beats, Cesium atom vibrations, ....but you have already specified one day which is 24 hours..

Your time measurement will only be effected by relativistic effects when you reach 90% of the speed of light (186,000 miles per second) so my guess is you will be measuring standard time.

Sincere regards,

Mike Stewart

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