# How far off from solar noon are you in your time zone when in standard time? **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [December 10, 2021, 10:51pm UTC](https://boards.straightdope.com/t/how-far-off-from-solar-noon-are-you-in-your-time-zone-when-in-standard-time/955861 "2021-12-10T22:51:14Z")\ **Posts on this page:** 9\ **Page:** 2
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [December 16, 2021, 12:22am UTC](https://boards.straightdope.com/t/how-far-off-from-solar-noon-are-you-in-your-time-zone-when-in-standard-time/955861/21 "2021-12-16T00:22:52Z")
> [@Keeve](#): > > > [@DPRK](#): > > > > Are you talking about the [Equation of Time](https://en.wikipedia.org/wiki/Equation_of_time)? > > I was going to answer “yes”, and then I read the beginning of the wiki article that you kindly linked to. > > That article says that the Equation of Time is about the difference between Apparent Solar Time and Mean Solar Time. But the comments we’ve been making about our localities are about the difference between Solar Time and Standard Time. > > I had thought that _(for a location whose longitude is an exact multiple of 15 degrees)_ Mean Solar Time is the same thing as Standard Time. But now I’m not so sure. @Hari_Seldon said that the time of noon varied for him: > [@Hari\_Seldon](#): > > Of course it varies through the year. Since I am at about 73 1/2 west, I know that, _on average_, our noon has to be 6 minutes early. Noon is always at 12:00 (apparent) Solar Time. So if he says the difference _varies_ and talks about the Earth’s orbit, he must be thinking about the Equation of Time. Initially skimming this thread, I thought it was about Mean Time, but @Hari_Seldon 's interpretation should be correct— the OP asks about “actual solar time”— though it also mentions “standard noon”, so I suppose we have to consider both. The Equation of Time does not depend on your time zone, though, just on where the sun actually appears in the sky vs. Mean Time. It varies more or less periodically. > [@Keeve](#): > > I had thought that _(for a location whose longitude is an exact multiple of 15 degrees)_ Mean Solar Time is the same thing as Standard Time. But now I’m not so sure. There is the old “Greenwich Mean Time”, where the name is rather a giveaway. And longitude is measured from Greenwich. 15 degrees equals 1 hour. But Standard zones like Chinese Standard Time and Iceland Standard Time seem to be defined according to political considerations (look at all the non-vertical-lines in the link in the first post), not necessarily so much the mean solar time. ---
**Author:** ![wolfpup](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolfpup/32/10618_2.png) [@wolfpup](https://boards.straightdope.com/u/wolfpup)\ **Post date:** [December 16, 2021, 12:30am UTC](https://boards.straightdope.com/t/how-far-off-from-solar-noon-are-you-in-your-time-zone-when-in-standard-time/955861/22 "2021-12-16T00:30:06Z")
12 minutes difference from solar time here. Good enough for me! On a bit of a side note, those who want to abolish time changes between Standard and Daylight Saving times mostly seem to want to settle on Daylight Saving throughout the year. I can understand the practical reasons for it from the standpoint of maximizing daylight in normal schedules and conserving energy, but it would put the vast majority of us much further out of sync with solar time, which seems rather contrary to what “time” (as in “time of day”) is supposed to mean in the first place. ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [December 16, 2021, 12:48am UTC](https://boards.straightdope.com/t/how-far-off-from-solar-noon-are-you-in-your-time-zone-when-in-standard-time/955861/23 "2021-12-16T00:48:05Z")
[timeanddate.com](http://timeanddate.com) claims that solar noon was at exactly 12:00 here on Dec 9-10 (which, I see now, is the OP’s post date). Today, it’s 12:02. In Feb, it gets up to 21 minutes off, but backs down again. ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [December 16, 2021, 12:55am UTC](https://boards.straightdope.com/t/how-far-off-from-solar-noon-are-you-in-your-time-zone-when-in-standard-time/955861/24 "2021-12-16T00:55:26Z")
Found an amusing bug with the site. Apparently, solar midnight “doesn’t occur” here on some days: [![](https://i.imgur.com/T32SuDX.png) ](https://i.imgur.com/T32SuDX.png) Coulda fooled me, but admittedly I wasn’t able to check if the sun disappeared on the other side of the Earth at exactly that moment. ---
**Author:** ![Riemann](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/riemann/32/3133_2.png) [@Riemann](https://boards.straightdope.com/u/Riemann)\ **Post date:** [December 16, 2021, 2:05am UTC](https://boards.straightdope.com/t/how-far-off-from-solar-noon-are-you-in-your-time-zone-when-in-standard-time/955861/25 "2021-12-16T02:05:57Z")
> [@Dr.Strangelove](#): > > Apparently, solar midnight “doesn’t occur” here on some days: I don’t think that’s a bug. I think that’s saying that there is no solar midnight on the date you are looking at. In this example perhaps the last one was at 11:59pm on the previous date, and the next one will be at 12:01am on the next date - barely more than 24 hours apart, but with nether one falling on this date. ETA: I can confirm that’s correct. I found a date when this happens for my location too. Solar midnight on the prior date is at 11:59pm, does not occur on the date in question, and then is at 12:00am on the next date. ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [December 16, 2021, 2:15am UTC](https://boards.straightdope.com/t/how-far-off-from-solar-noon-are-you-in-your-time-zone-when-in-standard-time/955861/26 "2021-12-16T02:15:11Z")
Oh, right. I guess that does make sense, since midnight is the transition between days. I suppose I had been thinking that it was indexing in reverse–that starting from a time it gave you a date. But that’s not it; you’re giving it a date and it tells you the time. And there will be one day a year where the gap is slightly more than 24 hours. And unlike solar noon, that gap can exactly straddle one day. ---
**Author:** ![Limmin](https://avatars.discourse-cdn.com/v4/letter/l/f04885/32.png) [@Limmin](https://boards.straightdope.com/u/Limmin)\ **Post date:** [December 16, 2021, 3:37am UTC](https://boards.straightdope.com/t/how-far-off-from-solar-noon-are-you-in-your-time-zone-when-in-standard-time/955861/27 "2021-12-16T03:37:33Z")
Similar to @Machine_Elf I am at the far western edge of the Eastern time zone, in my case, western Indiana. I might have it just as bad–or worse–in that I’m just to the E of a little bubble of central time zone that extends into Indiana, probably because of Chicago (it’s acknowledged as a Chicago suburb). The distance to this timezone boundary is only about 20 miles for me. So…sun rises and sets late. I guess that’s not so bad in the winter time. Nowadays (mid to late December) it doesn’t get bright until around 9AM. ---
**Author:** ![Treppenwitz](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/treppenwitz/32/3445_2.png) [@Treppenwitz](https://boards.straightdope.com/u/Treppenwitz)\ **Post date:** [December 18, 2021, 4:02pm UTC](https://boards.straightdope.com/t/how-far-off-from-solar-noon-are-you-in-your-time-zone-when-in-standard-time/955861/28 "2021-12-18T16:02:06Z")
Here’s a photo I took earlier today (but sadly not at noon) in Lewes, East Sussex. By my calculation (which I did at the time, and which I can’t be bothered to check now), my right foot would experience solar noon earlier than GMT, by something of the order of a millisecond. And my left foot would have a late noon by the same amount. [![Google Photos](https://lh3.googleusercontent.com/YmiG_8bs8cBBFEy2_6lBFZ_bXalN_0S2uAQoQBqHMXUQIKBDpLPFnBwpUXlCx07zyr1M8TSwW2hYRq3HgNwKPskd-2qs8RAqiXI4EHWKE5pDJhLiK251EMDTtyxLGBI0AEw7VxnLFA=w600-h315-p-k "New item by j") ](https://photos.app.goo.gl/6EVnt5T9QSV1rJG58) Eh, you’ll have to click on the photo to see my feet. There’s something I never thought I would type. j ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [December 18, 2021, 4:35pm UTC](https://boards.straightdope.com/t/how-far-off-from-solar-noon-are-you-in-your-time-zone-when-in-standard-time/955861/29 "2021-12-18T16:35:39Z")
Better your feet than other appendages. Can’t abide earlobe pics . . . [Previous page](https://boards.straightdope.com/t/how-far-off-from-solar-noon-are-you-in-your-time-zone-when-in-standard-time/955861.md?page=1)