If timezones go around the world each hour, how do people differentiate which one changes the date?


Like I get that 12AM is a new day, but if timezones go up by one hour every zone, that means that at one point, there’d be two next to each other who are on different days, right?


In: 0

Correct. And the border where that happens is the International Date Line and we put it in the Pacific Ocean where it affects the least amount if (major) nations.

That’s exactly how it works. In one place it’s 11 pm and in the next it’s 12 am of a new day. That’s why Guam is ‘where America’s day begins.’

We have the “International Date Line” which is roughly 180 degrees from the Prime Meridian which we base “0” off of for setting our clocks which has the time zone GMT/UTC-0

Yes, there must be a pair that changes date beyween them, it’s called the “International Date Line” for that reason. However does not exactly follow the line of 180° longitude as countries near it were allowed to choose which side to be on.

It’s where it is because a major international conference in Washington in 1884 decided for a number of reasons to make Greenwich in London the zero degree origin of the longitude scale. One of those was so the date line was in the Pacific and didn’t go through a land mass, which would have made things difficult for people living there.

Samoa. And the line is drawn weirdly went it gets to that area. I’m sure someone can explain why it was drawn like that.