zabkat support forum

here's the comment area for today's blog post found at
https://www.zabkat.com/blog/winter-sols ... riment.htm

Hi Nikos,
This is due to what is called the Equation of Time. Here is from Sunrise and Sunset Times Lag Behind
Sunrise and Sunset Times Lag Behind
The shortest day of the year is commonly associated with the latest sunrise and earliest sunset of the year. However, in most locations, the earliest sunset happens a few days before the solstice, while the latest sunrise occurs some days after it.
We also have to take into account the fact that the date of the December solstice varies in the calendar. Explanations on the same page.
More explanations at What Is the Equation of Time?
Καλή Χρονιά!

so now I must do the equivalent sunrise experiment to be certain

How cool or uncool are temperatures before sunrise in your area? Your kids might opt out and choose to cozy up against each other watching the Kardashians on TikTok…

Calendars were created to keep track of the seasons for planting, harvesting, birth control etc. Throughout the ages there were many calendars to deal with leap year, but leap year was and is a problem, interesting subject.

nikos wrote: ↑2023 Jan 04, 11:13 so now I must do the equivalent sunrise experiment to be certain

Naturally. And I hope that you've instilled enough curiosity and creativity in your kids that they, too, are eager to run another set of experiments and find out the real values.

Robert2 wrote: ↑2023 Jan 04, 12:30 How cool or uncool are temperatures before sunrise in your area? Your kids might opt out and choose to cozy up against each other watching the Kardashians on TikTok…

I would say that they probably didn't, considering they already did this 90-day project.

@Nikos - you think your kids might be willing to do both sunrise and sunset (yes, I know, that is a big ask of kids who also have schoolwork and school itself to deal with) for an entire year?

Robert2 wrote: ↑2023 Jan 04, 09:25 Hi Nikos,
This is due to what is called the Equation of Time. Here is from Sunrise and Sunset Times Lag Behind
Sunrise and Sunset Times Lag Behind
The shortest day of the year is commonly associated with the latest sunrise and earliest sunset of the year. However, in most locations, the earliest sunset happens a few days before the solstice, while the latest sunrise occurs some days after it.
We also have to take into account the fact that the date of the December solstice varies in the calendar. Explanations on the same page.
More explanations at What Is the Equation of Time?
Καλή Χρονιά!

Good analysis. So, what happens, then, is the total daylight hours of the sun are calculated, relative to your position on the earth, and the solstice still occurs anywhere from 20 Dec to 23 Dec, mostly 21 and 22 Dec, because the total day length is shortest on the solstice, right?

to be honest the kids didn't do this willingly, it was a chore I forced on them.

nikos wrote: ↑2023 Jan 06, 17:44 to be honest the kids didn't do this willingly, it was a chore I forced on them.

Ahhh. Then his analysis may be more on point!

Did they ever change their minds, especially when 'discovering' the variances?

I'll tell you in a few years if there are any subconscious effects

All I know is everything is confusing because not only is the orbit of the earth not a circle, but and ellipse, the earth is not dead center in this ellipse, plus it travels at different speeds depending on where it is in the ellipse. BTW, sunset happens when the upper edge of the sun disappears below the horizon. a lot of your photos appear to show the bottom touching touching the horizon, but I also notice a little hill off in the distance. The atmosphere also diffracts the sun rays so you see the sun disappear below the horizon a little later than it actually happen. And even though I'm aware of all the complications, I don't understand sunsets as well as I would like to.

Another thing is for the reasons I mention the days and nights aren't equal on the equinoxes, but that happens on the equilux, which I think in a few days earlier. In December I only care about the sunset times and I'm glad when they start to get later which is a week earlier than the solstice.

If you want something fun and astronomical to play with get the free planetarium Stellarium.
http://stellarium.org/