Top all-time · #1952
Stefano Maggiolo
Personal blog · blog.poormansmath.netmathscience
Stefano Maggiolo writes The poor man's math blog, a personal blog at blog.poormansmath.net about math and science. Since 2015, 38 different Hacker News readers have linked it 43 times, most often “How much is time wrong around the world”. The last post was in 2018, but the archive is still widely read.
Sometimes recommended · 5 of 30 sampled comments recommend it?
Why HN links it
HN readers link Stefano Maggiolo's blog for its maps of solar time versus clock time, used to discuss time zones, daylight saving time and sunrise and sunset times around the world.
- Recommended for · 5 comments
- Commenters call the solar-time maps a pretty good visualization, a beautiful visualization, a great map, and an interesting map, and one finds it pretty interes
Summarised by Claude from a sample of 30 HN comments that link here. Each comment is marked recommending, critical or neutral (citing without judging); how this works.
The poor man's math blog – By Stefano Maggiolo
Most-linked posts?
- How much is time wrong around the world12 people · 12 mentions · first linked 2015-07-02
- /images/SolarTimeVsStandardTimeV2.png10 people · 10 mentions · first linked 2015-11-16
- World map of the difference between solar and clock time8 people · 8 mentions · first linked 2015-10-02
- /images/SolarTimeVsStandardTime.png3 people · 3 mentions · first linked 2022-03-15
- Solar time vs. standard time on map2 people · 2 mentions · first linked 2022-01-23
- How much is time wrong around the world? (2014)2 people · 2 mentions · first linked 2018-07-06
What Hacker News says?
It depends where you are in your time zone. For a good chunk of the land in the US, DST is closer to solar time: http://blog.poormansmath.net/images/SolarTimeVsStandardTime.... But of course a whole lot of the population lives in the part where it's worse.
Comment linking /images/SolarTimeVsStandardTime.png
on “US Senate votes unanimously to make daylight savings time permanent”Submitted World map of the difference between solar and clock time as a story · 219 points
HN discussionThe average difference from solar time would still be larger with DST. You can find a pretty good visualization here: http://blog.poormansmath.net/images/SolarTimeVsStandardTime.... This shows the difference between solar time and standard time. By switching to DST you essentially shift the gradient to the east by an hour. Other than Greenland I can't see a timezone where that wouldn't mean that the longitude at whi…
Comment linking /images/SolarTimeVsStandardTime.png
on “US Senate votes unanimously to make daylight savings time permanent”Submitted How much is time wrong around the world? (2014) as a story · 80 points
HN discussionMost of the world already uses a standard time that is generally late relative to the solar time. See this map being colored mostly red, which means that the sun sets later than it "should" if we were just using solar time. http://blog.poormansmath.net/the-time-it-takes-to-change-the... By contrast, standard time in the "contiguous states" is much closer to solar time. Keeping DST would bring the US closer to the re…
Comment linking /the-time-it-takes-to-change-the-time/
on “American Academy of Sleep Medicine calls for elimination of daylight saving time”Submitted Pydepgraph – A dependencies analyzer for Python as a story · 3 points
HN discussionLooking at this map[1], it doesn't seem that bad. I mean sure, France, Spain and Benelux could move to +0, but other than that the time zones seem to match reasonably well to solar time all things considered. For example both Berlin and Rome seem to be pretty well matched. Notably it would seem like using summer time would make everything worse, shifting the time zones in wrong direction. [1] http://blog.poormansmat…
Comment linking /images/SolarTimeVsStandardTimeV2.png
on “EU to stop changing the clocks in 2019”Submitted Solar time vs. standard time on map as a story · 2 points
HN discussion> DST exists so that the sun doesn't rise around 5am. No, DST exists so the sun doesn't set around 6pm. > And that seems to be what the argument boils down to: "I don't want it bright too early". No, it's not "I", it's about "we the people", and "we the people" don't care as much about "bright too early", rather they care about "dark too early". Here is a map of the offset between solar noon and civil noon[0]. The b…
Comment linking /images/SolarTimeVsStandardTimeV2.png
on “Australia/Lord_Howe is the weirdest timezone”Submitted How much is time wrong around the world as a story · 2 points
HN discussionThanks for the picture, nice. I see it's from http://blog.poormansmath.net/the-time-it-takes-to-change-the... As the picture shows, Spain and the parts of France are the extremes in the Europe, in the rest of Europe the Sun is closer to being at 12:00 (not counting DST) not too different to Tokyo. Yes, the map you link shows is that some parts of the world have wider time zones than it would allow all the people liv…
Comment linking /the-time-it-takes-to-change-the-time/
on “Time to Dump Time Zones”Submitted How much is time wrong around the world? (2014) as a story · 2 points
HN discussionMy point is that 9AM in Tokyo and 9AM in Madrid or Virginia are vastly different in terms of "position of the sun", despite being the same longitude. http://blog.poormansmath.net/images/SolarTimeVsStandardTimeV... <-- this map shows the difference between clock time and solar time. Western Europe and much of the US is 2 hours behind solar time compared to Tokyo. So Tokyo is set to a 9-5, but if they want to follow t…
Comment linking /images/SolarTimeVsStandardTimeV2.png
on “Time to Dump Time Zones”Submitted Solar Time vs. Standard Time heat map chart as a story · 1 points
HN discussionWinter time is definitely crap for western europe, but I don't know how good or bad it is for eastern: CET is used from poland to france to spain so it covers a fair bit of territory, and the difference between solar and standard time is already negative: http://blog.poormansmath.net/images/SolarTimeVsStandardTimeV... FWIW remaining on summer time is the recommendation.
Comment linking /images/SolarTimeVsStandardTimeV2.png
on “EU to recommend that member states abolish daylight saving time”Submitted How much is time wrong around the world? (2014) as a story · 1 points
HN discussionMidnight on your clock is very likely tens of minutes or even hours offset from solar midnight, let alone seconds: http://blog.poormansmath.net/images/SolarTimeVsStandardTimeV...
Comment linking /images/SolarTimeVsStandardTimeV2.png
on “It’s time to leave the leap second in the past”Submitted The time it takes to change the time (2015) as a story · 1 points
HN discussionA good portion of the EU is in CET when they probably shouldn't be when it comes to solar time: * https://en.wikipedia.org/wiki/Time_in_Europe France should probably, AFAICT, be in WET (like the UK) and Spain definitely should be. Solar time offsets are quite off for them: * http://blog.poormansmath.net/how-much-is-time-wrong-around-t... * https://github.com/stefano-maggiolo/solar-time-vs-standard-t... * https://24t…
Comment linking /how-much-is-time-wrong-around-the-world/
on “Timezone Bullshit”Submitted The time it takes to change the time (2015) as a story · 1 points
HN discussionHere is a similar with NZ and friends so we can all focus on what the comment is saying instead repeating how 0.1% of the world's population isn't in the image: http://blog.poormansmath.net/images/SolarTimeVsStandardTimeV... I agree that we've let "what time is it" get conflated with too many other things - I'm not even sure time zones are the best answer for what people are actually looking for. Having the same tim…
Comment linking /images/SolarTimeVsStandardTimeV2.png
on “Opinion: Standard Time all year round is the healthy choice”Solar noon is already pretty far from clock noon for most people around the world. Time zones all but guarantee that. http://blog.poormansmath.net/how-much-is-time-wrong-around-t...
Comment linking /how-much-is-time-wrong-around-the-world/
on “U.S. Bill H.R.69 introduced – To make daylight savings time permanent”Solar noon coincides with noon for a pretty small amount of places, take a look at this map: http://blog.poormansmath.net/images/SolarTimeVsStandardTimeV... Only the thin stripes of white have it, for every other place solar noon is off by minutes, if not hours.
Comment linking /images/SolarTimeVsStandardTimeV2.png
on “European Parliament set to end EU-wide daylight savings”The local time of sunrise and sunset depends not only on latitude but also on the difference between local solar time and the local time zone’s time. According to http://blog.poormansmath.net/how-much-is-time-wrong-around-t... , that difference can exceed 90 minutes in Spain and even over 3 hours in western China. That’s the price they pay for China having a single time zone (that apparently was introduced by Mao Ze…
Comment linking /how-much-is-time-wrong-around-the-world/
on “Daylight saving time is 'not helpful' and has 'no upsides,' experts say”> There were 4.6 million replies [to the online] consultation, 70% of which were from Germans. Germans make up around 15% of the EU population. So by this metric they've got an out-sized democratic participation in the EU by a factor of almost 5x. As seen on a solar map [1][2] Germany isn't even particularly badly impacted by this issue compared to say France or Spain. There's some truth to the saying that Germany b…
Comment linking /how-much-is-time-wrong-around-the-world/
on “European MPs vote to end summer time clock changes”To expand a bit on why the localtime() is not enough, two factors are at play. First, the solar noon can be as much as two hours displaced from the timezone. This is basically time zone vs longitude. Second, depending on time of year and attitude you can go from having no daylight in the winter to no darkness in the summer. Solar noon details here: http://blog.poormansmath.net/images/SolarTimeVsStandardTimeV...
Comment linking /images/SolarTimeVsStandardTimeV2.png
on “Sct – set color temperature”There is an interesting map[1] that shows how much the time is off in each location in the world vs solar time. Japan is indeed ahead of solar time, as opposed to many other places on their longitude. (Though perhaps not by two hours). Interestingly, many more places are behind their solar time then places that are ahead of it. [1] http://blog.poormansmath.net/how-much-is-time-wrong-around-t...
Comment linking /how-much-is-time-wrong-around-the-world/
on “In Tuesday's Vote, California Opts for Year-Round Daylight Saving”This has also been done for Italy, by Stefano Maggiolo: http://blog.poormansmath.net/on-the-distribution-of-italian-...
Comment linking /on-the-distribution-of-italian-towns-by-their-endings/
on “A visual exploration of the spatial patterns in endings of German town names”The author is absolutely correct in claiming that the *importance* of time in a culture is... cultural. Timezones and DST are especially politically sensitive. See: https://blog.poormansmath.net/the-time-it-takes-to-change-th... Same for the ideas around what is a reasonable time to sleep, eat, work. There are all sort of biases for/against early risers and owls across different societies. Sounds like you and the ot…
Comment linking /the-time-it-takes-to-change-the-time/
on “The clock does not measure time; it produces it”DST is an issue, as is the political selection of time zones. There's a great map[1] that shows how arbitrary time zone shifts are. Even in the EU, the eastern edge of Finland is over an hour east of the center of CET, while western Spain is two hours west of it. That means that during the spring and autumn solstice, even though we have 12 hours of day and 12 hours of night, the sun over western Spain sets three hou…
Comment linking /how-much-is-time-wrong-around-the-world/
on “Time Zones Aren’t Offsets – Offsets Aren’t Time Zones”
