> so what you’re saying is there are indeed subtle differences and Northern California would have a tiny bit different time, but we just don’t acknowledge it?

Not really. The subtle difference between nearby places is in when the sun (and other things in the sky) rises and sets. There is no objective "time" at which these events occur. It's determined by the local horizon.

Muslims need to keep track of the sunset for fasting reasons. They are advised that if they happen to be at the top of the Burj Khalifa, they should remember that the sun sets three minutes later at the top of the tower than at the bottom. That doesn't mean it's "actually three minutes earlier" at the top of the tower. It's the same time as it is on the ground, it's just high up so the sun is above the horizon longer.

> the Julian calendar that added June and July as months

Usually this piece of incorrect trivia is cited as July and August, but regardless, it was January and February that were added to the end of the calendar. July and August were always there but were renamed. And the Julian calendar didn't add or rename anything.

Oh, and the Julian calendar had leap years too. The Gregorian calendar didn't add leap years, it took some away.

> Does it fluctuate due to earth’s topography or relative moon position (like tides)?

No, the definition of "space" is based on altitude above sea level, not local topography. In other words, there's not an extra "air mountain" above Mount Everest.

The Moon does pull on the atmosphere as it does the water, but this effect is negligible and also does not affect where space is defined to begin.

Canon is the official continuity of a franchise...it's what "really happened." What counts as canon depends on the franchise, as they all have different definitions.

If a part of a franchise is considered canon, that means the fans should expect other canon to respect what happens in that part, and not overwrite it; if something canon is ignored in other parts of canon, it becomes confusing.

For example, if your franchise is primarily a TV show, but it also has tie-in novels that you consider canon, then the writers of the TV show have to make sure that events in the show don't contradict events in the book, and vice versa.

The adaptations we make using science are just as natural as any other adaptation in any other organism. We're an organism that is clever enough to use science to survive. That's our niche.

Well what do you think "km" stands for?

Well, as a matter of fact, astronomers typically prefer the parsec over the light-year. A parsec is derived from the AU, is equal to 3.26 light-years, and is defined as the distance an object would have to be from the Sun to experience a parallax angle of 1 arcsecond (that's obviously not ELI5 but it's a digression).

The AU is better than the light-minute because the AU is a distance that we can easily understand. 3 AU is "three times the distance from the Earth to the Sun." I can wrap my head around that. What is 24 light-minutes? How far is a light-minute? You can tell me the equivalent in miles or kilometers, but the number is so big I can't conceive it as easily.

We can't easily conceive a light-year either, but when we get to distances larger than our solar system there isn't any easier measurement that we can grasp because it's way too far out of our range of human comprehension. The parsec doesn't help, and saying "thousands of AUs" doesn't help. We had to pick one, so we went with the measurement that sounds like it's a measurement of time and confuses everyone.

We don't know we have souls, and there is no reason to think that anything like a "soul" exists, except in that there are some qualities often ascribed to souls that are part of the mind or personality. Those qualities are entirely dependent on the physical brain, can be changed through physical means, and end with the death of the brain.

> There was no use case for a wireless router.

Well home wi-fi did exist. In 2002-ish my friend got an "antenna" that he attached to his laptop and we'd drive around the more affluent neighborhoods looking for wireless networks. No one who had wireless bothered to secure the network back then, and when we'd find one we'd go into the printer and make it print out various things ("help I'm stuck in the printer" or "YOU'RE FIRED"). Ah, youth.

There are many environmental conditions, especially at night, where you see just a light and not the rest of the fixture, so if you don't know what color it is you can't determine if it's the top or bottom. It usually becomes apparent up close but until then you would need to guess whether you should be stopping or not, and we don't need people guessing on the road.

We call the Pole Star the "Pole Star" because it happens to sit directly over the North Pole. Over the centuries the sky shifts and the pole points to different stars; in our century it just so happens that the star we call Polaris sits almost exactly over the North Pole, where usually it or another star is just in the general vicinity. Since the Earth rotates around the pole, the Pole Star never moves in the night sky: all the other stars appear to circle around it over the course of a night.

So if the North Pole was an actual pole that stuck out of the Earth and kept going forever, Polaris is where you would see that pole. If you were standing at the North Pole itself, Polaris would be directly over your head, at the top of the sky. If you were at the equator, it would be right at the northern horizon and you might not be able to see it at all. If you were south of the equator it would be below the horizon, but the southern pole star would now be in view (at the moment there is no bright southern pole star, so we use the constellation Crux which points to it).

And if you are somewhere in between the North Pole and the equator, as is the case with North America, Europe, and Asia, then the Pole Star would be somewhere in between the horizon and the top of the sky. It in fact represents your latitude on Earth; I live at exactly 45 degrees N latitude so Polaris sits at 45 degrees up in the sky. Wherever that star is, that's where North is.