[Tom Bishop]

Your Solar Day link says that the Solar Day is 24 hours long

The leap year happens because the year is 365.25636 days long. Why are you trying to use that as an explanation when that is already accounted for in the number.

[Tom Bishop]

The link Tumeni provided does say that Solar Day is technically "24.0000006 hours"

https://en.wikipedia.org/wiki/Day#Apparent_and_mean_solar_day

In recent decades, the average length of a solar day on Earth has been about 86 400.002 seconds (24.0000006 hours) and there are about 365.242 2 solar days in one mean tropical year.

Lets divide those numbers:

Solar Day: 24.0000006 hours
Year: 365.2422 Solar Days in a Year

Year / Day = 15.21842461953938

Oh no. This is not a whole number. Even with the more accurate numbers this doesn't work.

They put their contradiction right there in the same sentence, and even specified that it is Solar Days in both cases.

[Tumeni]

I don't know why you are talking about the movement of the stars in relation to the sun.

He's not. The star is merely a reference point. Look again at the first wikipedia page I linked for you. (Illustration in wiki referred to in reply #13)

Solar Time has a 24 hour cycle. That cycle does not fit into the length of the year of 365.25636 days.

... and the 0.25 is carried forward to the leap year.

Easy one, right? Just divide and we will get a whole number. But that is not what happens. The days don't fit.

Because it's a meaningless calculation. Dividing any number of days by the number of hours in a day won't produce anything meaningful.

Divide 24 (days) by 24 (hours) and the answer is 1, divide 48 (days) by 24 (hours) and the answer is 2.

72 days = 3
96 days = 4

What does that mean to you?

See my examples above based on weeks and days.

[Stagiri]

@Tom Bishop
Premises:

• 1 day = 24 hours
• 1 hours = 3600 seconds

1/2 day = 12 hours
12/3600 = 0.0033333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333(and so on) = not an integer

Oh no! Conclusion: seconds do not fit into 1/2 day 

[Tumeni]

@Tom Bishop
Premises:

• 1 day = 24 hours
• 1 hours = 3600 seconds

1/2 day = 12 hours
12/3600 = 0.0033333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333(and so on) = not an integer

Oh no! Conclusion: seconds do not fit into 1/2 day 

Exactly. Tom, please see reply #25 again.

[garygreen]

This is very easy to understand, Gary. I don't know why you are talking about the movement of the stars in relation to the sun. We are not talking about Star Time.

because comparing sidereal days to solar days demonstrates that the image you posted makes perfect sense.

Lets break it down even simpler. Let not talk about half of the year. Lets talk about the full year. Very basic.

The Solar Time has a 24 hour cycle. That cycle does not fit into the length of the year of 365.25636 days.

Easy one, right? Just divide and we will get a whole number. But that is not what happens. The days don't fit.

i get it.  you believe that a tropical year and a sidereal year must have an integer ratio.

sorry, but that isn't part of the model.  it's just bogus requirement you made up.

[Tom Bishop]

@Tom Bishop
Premises:

• 1 day = 24 hours
• 1 hours = 3600 seconds

1/2 day = 12 hours
12/3600 = 0.0033333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333(and so on) = not an integer

Oh no! Conclusion: seconds do not fit into 1/2 day 

Why are you placing the hours integer first when the goal is to see if seconds fits into hours?

You need to put in the numerically bigger number first if you are looking to see if the small number fits into it.

3600 / 12 = 300 = The ratio works. Whole number.

Conclusion: A second fits into an hour.

[Tom Bishop]

We have 8 mysterious pieces of a pizza pie that are the same size and a pizza tray that holds 8 pieces.

We see that the two pieces make up 2/8th's of the pizza tray.

Can we calculate whether, if put in all 8 of the pizza slices (that are of the same size, if you recall above) of the pizza pie, would they fit?

8 / 2 = 4 -- Yes, these are whole slices that will all equally fit into the pizza tray. Tray divided by pizza slices. The result is a whole number. All 8 will fit.

2 / 8 = 0.25 -- This is not a valid equation for the purpose of this. Pizza slices divided by Tray? You need to put the larger numerical integer first to see if the smaller integer fits into it by producing a whole number.

[garygreen]

this is a weird argument.  there is nothing in physics that says planets have to complete integer numbers of rotations in a single orbital period.  you're just manufacturing this criticism.

[Curious Squirrel]

We learned earlier that a half year later, a sidereal day and a sun day are 12 hours apart. On one side of the sun they coincide, on the other side they are opposite. Since the only relationship that has changed is Earth to sun, the sidereal noon occurs at the same relative time that it did half a year ago, and solar noon now occurs 12 hours different. Oh wow, that makes solar noon continue to be during the day doesn't it? You're bringing in a requirement that doesn't exist and proclaiming it proves everything wrong. It's already been shown the difference between the two is 12 hours over the course of half of a year. Since the relative location of the stars to Earth doesn't change, that means the sun has done exactly what we experience every year. QED.

[Tom Bishop]

We learned earlier that a half year later, a sidereal day and a sun day are 12 hours apart. On one side of the sun they coincide, on the other side they are opposite. Since the only relationship that has changed is Earth to sun, the sidereal noon occurs at the same relative time that it did half a year ago, and solar noon now occurs 12 hours different. Oh wow, that makes solar noon continue to be during the day doesn't it? You're bringing in a requirement that doesn't exist and proclaiming it proves everything wrong. It's already been shown the difference between the two is 12 hours over the course of half of a year. Since the relative location of the stars to Earth doesn't change, that means the sun has done exactly what we experience every year. QED.

Sidrael Day is Star Time, and has nothing to do with this. What does it matter how fast the stars are moving in this?

Tumni has already settled the matter, by providing this link, right here:

The link Tumeni provided does say that Solar Day is technically "24.0000006 hours"

https://en.wikipedia.org/wiki/Day#Apparent_and_mean_solar_day

In recent decades, the average length of a solar day on Earth has been about 86 400.002 seconds (24.0000006 hours) and there are about 365.242 2 solar days in one mean tropical year.

Lets divide those numbers:

Solar Day: 24.0000006 hours
Year: 365.2422 Solar Days in a Year

Year / Day = 15.21842461953938

Oh no. This is not a whole number. Even with the more accurate numbers this doesn't work.

They put their contradiction right there in the same sentence, and even specified that it is Solar Days in both cases.

[Curious Squirrel]

We learned earlier that a half year later, a sidereal day and a sun day are 12 hours apart. On one side of the sun they coincide, on the other side they are opposite. Since the only relationship that has changed is Earth to sun, the sidereal noon occurs at the same relative time that it did half a year ago, and solar noon now occurs 12 hours different. Oh wow, that makes solar noon continue to be during the day doesn't it? You're bringing in a requirement that doesn't exist and proclaiming it proves everything wrong. It's already been shown the difference between the two is 12 hours over the course of half of a year. Since the relative location of the stars to Earth doesn't change, that means the sun has done exactly what we experience every year. QED.

Sidrael Day is Star Time, and has nothing to do with this. What does it matter how fast the stars are moving in this?

Tumni has already settled the matter, by providing this link, right here:

The link Tumeni provided does say that Solar Day is technically "24.0000006 hours"

https://en.wikipedia.org/wiki/Day#Apparent_and_mean_solar_day

In recent decades, the average length of a solar day on Earth has been about 86 400.002 seconds (24.0000006 hours) and there are about 365.242 2 solar days in one mean tropical year.

Lets divide those numbers:

Solar Day: 24.0000006 hours
Year: 365.2422 Solar Days in a Year

Year / Day = 15.21842461953938

Oh no. This is not a whole number. Even with the more accurate numbers this doesn't work.

They put their contradiction right there in the same sentence, and even specified that it is Solar Days in both cases.

Ah yes, your made up requirement doesn't work. Pity that, I suppose it's a good thing it doesn't mean anything. In fact, since we don't have a whole number of days in a year, why would you ever expect this division to result in a whole number? It's almost as though you're just making something up and claiming it disproves something else.

You originally asked about solar noon changing the side of the planet it's facing. This is readily answered in the difference between solar noon and sidereal noon. Over half of a year they end up 12 hours, or half a rotation apart. Since we know the stars don't move in relation to Earth by 180 degrees, obviously the sun does. Which leaves solar noon still happening on the day side of the Earth. Which shows your original objection is groundless.

[Tom Bishop]

I believe that I have shown a significant error in Solar Time, which is the heart of this discussion.

Lets define Tropical Year

https://en.wikipedia.org/wiki/Tropical_year

A tropical year (also known as a solar year) is the time that the Sun takes to return to the same position in the cycle of seasons, as seen from Earth; for example, the time from vernal equinox to vernal equinox, or from summer solstice to summer solstice.

And the Topical Year varies on solar return points (which is why they called it the 'mean' tropical year):

http://calendars.wikia.com/wiki/Tropical_year

Current values and their annual change of the time of return to the cardinal ecliptic points[2] are:

    vernal equinox: 365.24237404 + 0.00000010338×a days
    northern solstice: 365.24162603 + 0.00000000650×a days
    autumn equinox: 365.24201767 − 0.00000023150×a days
    southern solstice: 365.24274049 − 0.00000012446×a days

Lets compare the smallest value to the largest value.

365.24162603 / 24.0000006 = 15.218400704

365.24274049 / 24.0000006 = 15.218447139

The difference isn't anywhere close to a whole number. This is way off.

[Tumeni]

Sidrael Day is Star Time, and has nothing to do with this. What does it matter how fast the stars are moving in this?

Nobody is saying that it does matter. You seem to be manufacturing something to argue against.

Again, see https://en.wikipedia.org/wiki/Solar_time

References to a 'distant star' are merely as a reference point, a presumed stationary reference point ...

[Tumeni]

The difference isn't anywhere close to a whole number.

So what?

[Devils Advocate]

Watcha Tom,
I'm wondering if your issue is more of a problem with the calendar as opposed to astronomy?

[Tumeni]

Lets compare the smallest value to the largest value.

365.24162603 / 24.0000006 = 15.218400704

365.24274049 / 24.0000006 = 15.218447139

The difference isn't anywhere close to a whole number. This is way off.

Once again, you're a dividing an arbitrary number OF days by the number of hours WITHIN a day and expecting some correlation, when none is expected by anyone. ever.


As an aside;

The currency system in the UK used to be pounds, shillings and pence

1 pound = 20 shillings
1 shilling = 12 pence

You're doing the equivalent of

1 (pound) divided by 12 (pence) = 0.08333 .... oh, no, the currency system doesn't work (unless you divide 12 pounds by 12 pence, and get 1; or 24 pounds by 12 pence to get 2, 36 by 12 = 3, 48 by 12 = 4 ......) !

...

[inquisitive]

I believe that I have shown a significant error in Solar Time, which is the heart of this discussion.

Lets define Tropical Year

https://en.wikipedia.org/wiki/Tropical_year

A tropical year (also known as a solar year) is the time that the Sun takes to return to the same position in the cycle of seasons, as seen from Earth; for example, the time from vernal equinox to vernal equinox, or from summer solstice to summer solstice.

And the Topical Year varies on solar return points (which is why they called it the 'mean' tropical year):

http://calendars.wikia.com/wiki/Tropical_year

Current values and their annual change of the time of return to the cardinal ecliptic points[2] are:

    vernal equinox: 365.24237404 + 0.00000010338×a days
    northern solstice: 365.24162603 + 0.00000000650×a days
    autumn equinox: 365.24201767 − 0.00000023150×a days
    southern solstice: 365.24274049 − 0.00000012446×a days

Lets compare the smallest value to the largest value.

365.24162603 / 24.0000006 = 15.218400704

365.24274049 / 24.0000006 = 15.218447139

The difference isn't anywhere close to a whole number. This is way off.

So you have discovered something nobody else has?

[Macarios]

Earth takes the same position relative to orbital event in 31 556 925 seconds.
It is called Tropical Year.
During that time it turns 365.2421875 times.
Which means, it completes 365 turns about 0.242 days earlier than making full circle.

Our 24 hours day was designed to have 86400 seconds in one Solar day.
(The 86400 is on average, plus or minus 18 to 29 seconds due to speed changes in accordance with Kepler's Second Law.)
One solar day is time until the same meridian points towards Sun again.
It is not 360 degrees, it is 360.9856 degrees (almost 361).
It is because Earth moved forward in orbit and has to "look a bit back" to point the Sun again.

Time required to spin for 360 degrees is Sidereal day, and is measured towards distant, apparently unmovable star.
It is not 24 hours, but a bit shorter, 23 h, 56 min, 4.1 sec.
For our calendar it is irrelevant.
When people designed calendar they didn't know about it.
They designed day based on Sun, nor on stars, and year based on whole number of such days.

Astronomers at the time of Julius Caesar noticed that there is difference between solstices and full set of 365 days.
To correct that error they added one more day every four years to compensate for those 6 hours.
That's how Julian calendar was created.
It measures 31 557 600 seconds per year and still doesn't hit the exact number of 31 556 925 seconds.

The time between the full 365 days and the full orbital circle wasnt exactly 6 hours, it was 5 hours 48 minutes and 45 seconds.
The difference accumulated by adding one unnecessary day every 127 years.

At the time of Pope Gregory XIII the error accumulated to 10 days.
Calendar was late.
Instead of showing 21st of March for vernal equinox, it was still showing March 11th.
Solstices weren't at the same dates as in the time of Julius Caesar.
So, calendar was corrected again, and extra days were removed by skipping them.
Thursday, 4 October 1582 was followed by Friday, 15 October 1582.
Some non-catholic countries didn't accept the change yet.
Few haven't until 19th or even 20th century.
Meanwhile their error grew by one more day every 127 years.
Now you understand how "October Revolution" in Russia started in 1917 on October 25, while it was November 7 in the rest of the world.
(NASA didn't exist until 1958.)

Additionally, to prevent further accumulation of error, changes were made:
Julian calendar simply adds one leap day every 4 years.
Gregorian calendar does the same, except for years divisible by 100 but not by 400.
So, years 1700, 1800 and 1900 weren't leap years, but 2000 was.
Years 2100, 2200, 2300 won't be leap years, but 2400 will be.

Old Julian calendar makes 1 day error every 127 years.
Gregorian calendar measures 31 556 952 seconds and is in error for 26.7 seconds.
Gregorian calendar is off by 1 day every 3236 years.

What you say would happen with Sun (6 months later on the other side of Earth) actually happens with stars and constellations.
It is because of difference between Solar day and Sideral day.
In different times of the year the night side of Earth points to different stars and constellations.
Ever heard of Summer Triangle, or Winter Hexagon?

[AATW]

I haven't been following the maths in this closely but I suspect this argument is as spurious as saying:

"Wait, round earthers, so you're claiming there are 365 days in a year and 52 weeks in a year BUT you're also claiming that there are 7 days in a week.

365/52 = 52.142857...

So weeks don't fit into a year. Checkmate!"

A day (on any planet) is how long it takes to rotate on its access.
A year (on any planet) is how long it takes to orbit its star.

Length of a year / length of a day doesn't have to be an integer, it would be weird if it was.