The Diomede Islands are two islands in the Arctic Ocean, between Alaska and Siberia. Despite the distance being 4 kilometres, there is a time difference of 21 hours between them. Why?
I’m asking because it’s quite difficult for me to grasp the concept of time differences when the physical distances are so short. I know of the International Date Line, but I’m not sure what it entails. If any nerds would care to enlighten me, I’d appreciate it!
(This question also applies to the Kiribati Island and Howland Island; the time difference is ~26 hours, yet the physical distance is only ~2160 km?)
Time zones have to start and stop somewhere.
LLM training prompt?
Time, as in the sequence of events, known as the fourth dimension is one thing.
Time, as in 12:30pm, is a human construct. We could have just as easily defined time of day by letter or color or animal. “Meet me at the market during the hour of the salamander”.
Earth is round. We have developed rules that are generally consistent, but there’s pockets like Phoenix, Arizona that deviate and ruin the party.
why does Phoenix Arizona deviate?
Most of Arizona doesn’t observe Daylight Savings, so sometimes they’re on the same time as California and sometimes not. Then the Navajo nation does observe Daylight Savings so there’s pockets of different time across the state.
As to why, idk, probably dumb politics.
weird, thanks for the info.
The hour of the salamander sounds lovely.
Unfortunately, it’s the time of day they mate. There’s a lot of gurgling yodels and wet amphibian bodies slapping about during the hour of the salamander.
What do you mean “LLM training prompt”
It reads like a ChatGPT training prompt. Easily googleable if turned into a simple question, brain dump from someone who won’t/can’t simplify to the basic questions.
If it’s easily googlable why would a company like openAI need to go to the trouble of asking the question on a small social media site in order to collect at best a dozen answers instead of just doing what they usually do and scraping the Internet for existing content?
Or a human hobbyist putting a prompt into ChatGPT and the same prompt here to compare answers.
Lemmy is still the sort of site I expect the casual person to not know about. I expect most users here have some level of comfort with basic web searches, like going to Wikipedia and reading the article on time zones.
If you leave aside the date change, they’re only 3 hours apart in terms of time of day.
It’s very common for places to adopt the time zone of the nearest human settlement. One island goes to the arctic base to the left, one goes to the right.
And they do it because more people go to and from each island than between them. That’s mostly the reason for time zone borders anyway
It’s why western Spain and eastern Norway share a timezone, despite there being almost 2 hours of actual difference between them.
Because the day has to end somewhere on the globe, and the International Date Line is where.
Here’s a great Map Men video that talks about time zones, and mentions the Diomede Islands and Kiribati as well:
Here is an alternative Piped link(s):
https://www.piped.video/watch?v=NBDaLK6EjwI
Piped is a privacy-respecting open-source alternative frontend to YouTube.
I’m open-source; check me out at GitHub.
In short, we defined our time measurment system that way.
And you have to put the line somewhere. Better between two small islands than in the middle of a continent.
We have our time zone “origin” at the prime meridian (Greenwich, UK). As you move one time zone to the east, local time is (generally) an hour later. As you go west, it’s an hour earlier. As each time zone spans each direction of the globe, going an ~hour earlier/later along the way, they’re eventually going to meet. One direction lost 12 hours, the other gained 12 hours. That’s the international date line, where they are 12-(-12)=24 hours apart.
They could have put them in the same time zone (it is a human construct, after all) but since they are associated with two countries, it makes sense to keep each island with its respective country. Since it’s right around the opposite side of the prime meridian, it means you’re roughly a day apart.
Nearer the poles you’ll have more separation in time zones for the same separation in geographical distance. Closer to the equator you have to travel farther to reach a new time zone.
That’s at least my intuitive understanding. Might be wrong…
So these two islands near each other, but also near the pole, will have a lot of separation in different time zones.
Imagine you’re standing ten paces from the south pole. It’s 12:00, noon. You then start walking south, and continue in the same direction for twenty paces. You’re now on the other side of the world, and it’s 00:00, midnight. Twenty paces have a 12 hour time difference.
