The Clock
blog.senko.net
blog.senko.net
A [solar] day is the time between noons, which is slightly more than one rotation on our axis. A single rotation is a [sidereal day] — the Wikipedia article has a good animation.
(The ellipse part of our orbit means the length of a solar day isn't consistent, as the rotation required to get back to pointing at the sun isn't the same throughout the year, which is what leads to mean solar time. The the article doesn't want to do ellipse orbits, which is fine… for a moment… but…)
> When the tick comes directly under the sun, that's (solar) noon, and one full rotation is one day.
But this is sort of where if you do you MST (if you have a fixed day length, you are), then when the tick is directly under the sun it won't necessarily be noon. The difference (between MST & solar) is like 17 minutes at its peak. The aliens will be looking at this going "it's uh… close? But off."
I still think "solar time" is a cultural assumption, though I do think there's a high likelihood of aliens sharing that assumption. But one might also imagine a species on a tidally locked world (maybe having grown up in the twilight region) with no concept of "days".
[sidereal day]: https://en.wikipedia.org/wiki/Sidereal_time
I had a fuzzy sense of these differences but had no idea that MST/solar is 17 minutes off - that's a lot! Of course there's also the difference between this and proper clock time (depending on where in your timezone you're located), and the clock shows clock time.
[This Wikipedia article](https://en.wikipedia.org/wiki/Solar_time#Mean_solar_time) has what I think is a good intuition here:
> Long or short days occur in succession, so the difference builds up until mean time is ahead of apparent time by about 14 minutes near February 6, and behind apparent time by about 16 minutes near November 3.
With the really nitty gritty being here: https://en.wikipedia.org/wiki/Equation_of_time#Concept
> Of course there's also the difference between this and proper clock time (depending on where in your timezone you're located), and the clock shows clock time.
"Standard time", yes, will be different yet. I didn't comment on that b/c the whole article is, of course, building a clock that unmoors us from cultural conventions, and I think Standard Time falls very squarely in the "cultural convention" bucket. So it's more of a solar clock in that sense.
I wanted the year circle to evoke Earth's orbit, so it had to be near the Sun. Inserting another circle was breaking that intuition (already stretched, tbh) for me. I was flip-flopping between these two and finally decided on the current solution.
I'm even more unhappy[0] with the fact that the number of ticks and speed on that circle changes every month, depending on the calendar month duration. For a world clock, on month changes it also means that you can't represent the date correctly for all shown timezones.
I could have used some real-world phenomena that are close to our calendar month instead[1], as pointed out by another commenter. This would make it "more correct" but "less useful in everyday situations". Even though I don't plan to use it every day, one of the goals of the project was for it to aspire to being useful.
[0] unhappy is a strong word; I mean I'm not satisfied with the solution, but was unable to find one I feel better about [1] https://en.wikipedia.org/wiki/Lunar_month#Types
https://clocks.specr.net/solar-system
Senko you might also be interested in this one - it doesn't go into the same depth as yours but it's visually similar.
I love your reinterpretation of time as a mini solar system. On impulse I tried to drag to rotate it and it worked, was delighted!
I was confused for a bit on what that satellite orbiting Moon is, and why the Moon is blue, before realizing how it works, so was a mini puzzle for me too :)
There might be a natural, Schelling division to use -- the same ratio year:day could be applied, day:minute. Thus, the day can be broken up into 365.25 "Schelling-minutes" (corresponds to 3.94 SI minutes), and further into 365.25^2 "Schelling-seconds" (corresponds to 0.65 SI seconds). I think it's interesting that we get something not too distant from our own minutes and seconds if we do this.
Of course, for practical daily usage, lacking anything similar to an hour would be a problem. A "half-division" might be in order; that is, √365.25, or roughly 19.11 divisions of the day. Sure, that's close enough to SI hours... but it's probably worth remembering that there's a reason we don't like to use fractional divisions. :P
The end result is: https://senko.net/clock/
Tech trivia: implemented as a reusable web component, powered by CSS animation, JS is just used to set up the initial state.
Some feedback:
I could not catch that the circle meant the sun. I did catch seconds, minutes, day, month, and I deduced TK meant Tokyo and SF meant San Francisco and could not deduce the city ZG represents. So, I don' think you can actually be free of baggage. Some minor things bugging me: - The lines at the bottom don't align! Really annoying, I spent a lot of time trying to understand it meant something or not. - Dark mode shows only 1 city. I could not understand what TK meant until I saw SF.
Some advice:
- Change the pictoric representation of the sun for something a bit more "sunny". Some flames feel like something not cultural (since there literally is solar activity at the surface), so aliens could get that it is the sun. - In the intro you say there is a puzzle, but you don't say what the puzzle is. I thought it might be some interactive thing. It was only until I gave up I start reading the explanation and got that the puzzle is to understand how the clock works, given it has no cultural baggage. Then I went back to try to understand it. Maybe add a little explanation somewhere saying the intention.
If you turn off the numbers you get a pretty decent and (i think anyway) culturally assumption-free clock. It tracks the sun and moon, shows the seasons (in #calendar). The direction it turns matches the way the Sun moves in your hemisphere.
More generally, I think 24-hour analogue clocks are already pretty culturally neutral — I don't understand why we ended up with 12-hour clocks being the dominant form.
Main changes are greater information density and minor modifications to the movement mechanism. Site has themed examples and a tutorial.
Does the arc length signify anything? Wasn't able to figure it out, and as far as I can see, it isn't explained.
Deliberately not half so you can tell what is foreground/background irrespective of color scheme.
I did explain design thinking in early versions of the tutorial, but it made it too long.
As it is now, "now" is at different places at the different circles.,.,.
Turns out if you want to have a useful clock it needs to use the social/cultural constructs. This was not at all obvious to me before I started with the project, but now, especially after the discussions here and elsewhere, it looks unavoidable.
Or to quote one of my favorite books: "Time is an illusion. Lunchtime, doubly so."
It's really not obvious, especially in light mode, but if you switch to dark mode you can see the day circle has a "bolder" and a "thinner" part. Bolder is the daylight hours, and its length and position corresponds to the daylight hours (in this instance, of Zagreb, since that's the primary timezone for the clock).
You're correct in that it can't work if you have multiple lattitudes. I took the easy way out - I ignore that and just use the first one :X
I had thought that months aren't quite a human construct, they correspond roughly to lunar cycles. Weeks were a way to carve the month up into the four lunar phases per cycle.
Seconds, minutes, hours, etc. are, as you say, all sexagesimal math bias.
Referencing actual phenomena would be more elegant - but wouldn't show correct date (see my comment here https://news.ycombinator.com/item?id=47686522)
This is a charming clock :)
Erm, WTF? DST does not change when dawn and sunset occur relative to solar noon. So what exactly is this showing?
Rereading the post, I notice I haven't made that distinction clear.
One nitpick on the day/night line: This is strongly dependent on the latitude, i.e. it kind of collides with your notion of the world clock. Maybe you boldface the label for the city to which it is referring.
so, kudos to the author at Senko.net!