[garygreen]

That's the definition of a Solar Year. The time it takes the sun to return to its same position. I have given you the quote.

i understand that you're talking about solar years.

a solar year is not the same the same length of time it takes for the earth to orbit the sun once.  or: a tropical year is not the same duration as the earth's period around the sun.

there is no requirement in ret that tropical years and orbital periods be the same.

[Tom Bishop]

That's the definition of a Solar Year. The time it takes the sun to return to its same position. I have given you the quote.

i understand that you're talking about solar years.

a solar year is not the same the same length of time it takes for the earth to orbit the sun once.  or: a tropical year is not the same duration as the earth's period around the sun.

there is no requirement in ret that tropical years and orbital periods be the same.

Are you suggesting that a Solar Day is not 24 hours? Are you suggesting that the Solar Year varies in length greater than the numbers I've given? Look up Solar Day. It is the Day as it relates to the Sun.

https://community.dur.ac.uk/john.lucey/users/e2_solsid.html

Solar time is time measured with respect to the Sun's apparent motion in the sky. The clocks we use for civil timekeeping are based on this motion. Of course, the apparent motion of the Sun across the sky is actually caused by the rotation of the Earth. So, our clocks measure the length of time required for the Earth to rotate once with respect to the Sun. From our perspective, the Sun revolves around the Earth every 24 hours. This period is known as a solar day.

[garygreen]

Solar time is time measured with respect to the Sun's apparent motion in the sky. The clocks we use for civil timekeeping are based on this motion. Of course, the apparent motion of the Sun across the sky is actually caused by the rotation of the Earth. So, our clocks measure the length of time required for the Earth to rotate once with respect to the Sun. From our perspective, the Sun revolves around the Earth every 24 hours. This period is known as a solar day.

which is longer than the time required for the earth to rotate once with respect to its axis.  a solar day is longer than a sidereal day.

sigh.  last try: http://astro.unl.edu/naap/motion3/sidereal_synodic.html

A synodic year is the time it takes for a planet-sun alignment to reoccur. For the case of the sun, it is the time it takes the sun to come to the same place on the ecliptic (equinox to equinox) and is called a Tropical Year. A tropical year is 365.242 mean solar days (366.242 sidereal days). It is just over 20 minutes shorter than a sidereal year (again, the effect of precession).

everyone in astronomy is already very well aware that the earth does not rotate an integer number of times in one orbit.  there's no reason it should have to.  it would be a noteworthy coincidence if it did.

[Tom Bishop]

Gary, the earth rotates 24 hours in relation to the sun. The earth rotates slightly slower in relation to the stars. Why do the stars matter? If the stars did not exist the Solar Day and Solar Year are still wrong.

Lets try to do the math on this.

The Sidrael Day is about 4 seconds less than the Solar Day.

4 x 365.24 / 60 / 60 = 0.4058 hours. This is nowhere close to the 5.76 hour offset that I got with Solar Time:

The sun travels across the earth's surface each day. In Solar Time: There is 1 Solar Day in 24 Hours. There are 365.24 Days in a Solar Year.

Earth circumference = 24,901 mi. In 1 Day the sun travels over 24,901 mi. of earth.

24,901 / 24 = 1037.54166667 miles. Over 1 hour the sun travels over 1037.54166667 miles

After 365 days:  24,901 mi. x 365 days = 9088865 miles

After 365.24 days:  24901 x 365.24 = 9094841.24 miles

Difference = 5976.24 miles

5976.24 miles / 1037.54166667 miles = 5.76. The hours in miles fits into the difference by 5.76 times. Where are those extra hours coming from? The sun will not be in the same place over the earth.

[Curious Squirrel]

Tom, a solar year and a solar day (despite having similar names) have no required correlation. Presuming they do is getting you into trouble. A solar year is defined by the sun returning to a specific ecliptic, or arc through the sky. NOT a specific point IN the sky. You've been missing this important point this whole time it seems, it looks like it hasn't been included when you copy the definitions over. The equinoxes are pretty normally spaced apart. Yet they can vary (according to the calendar) between some point in two different days. Do you wonder why that is if they're so consistent? It's because of the difference between Earth's orbital period, and it's rotational period. Which, once again, have no requirement to be correlated in any way outside of your own mind.

[inquisitive]

Gary, the earth rotates 24 hours in relation to the sun. The earth rotates slightly slower in relation to the stars. Why do the stars matter? If the stars did not exist the Solar Day is still wrong.

Lets try to do the math on this hunch you have.

The Sidrael Day is about 4 seconds less than the Solar Day.

4 x 364.24 / 60 / 60 = 0.4072 hours. This is nowhere close to the 5.76 hour offset that I got with Solar Time:

The sun travels across the earth's surface each day.

Earth circumference = 24,901 mi. In 1 Day the sun travels over 24,901 mi. of earth.

24,901 / 24 = 1037.54166667 miles. Over 1 hour the sun travels over 1037.54166667 miles

After 365 days:  24,901 mi. x 365 days = 9088865 miles

After 365.24 days:  24901 x 365.24 = 9094841.24 miles

Difference = 5976.24 miles

5976.24 miles / 1037.54166667 miles = 5.76. The hours in miles fits into the difference by 5.76 times. Where are those extra hours coming from? The sun will not be in the same place.

Why do you need to discuss this here when there are explanations online.  Do you think you have discovered something?

[AATW]

The rotational and orbital duration should have constant ratios.

This bit is actually true. The ratio between how long the earth takes to rotate on its axis - 1 day, that is actually the definition of a day - and how long the earth takes to orbit the sun should be constant. And it is, it’s 365.24. That IS the ratio, and it is constant but it is not an integer, nor does it need to be. There is no law of physics which says it does. If you put a spinning top on a roundabout and spin the top and the roundabout at certain speeds the number of times the top spins while the roundabout revolves once does not need to be an integer. It would be a pretty amazing coincidence if it was.

It is not merely arbitrary that the number of hours in a day should fit into the number of days in a year.

Yes it is.
They are completely different units.
The number of HOURS in a day should fit into the number of HOURS in a year but that’s about it.

The number of days in a year is defined by how many times the earth rotates as it orbits the sun - can we agree that this number is fairly random? All the planets rotate at different speeds depending on their distance from the sun.
The number of hours in a day is a definition which seems to come from the ancient Egyptians. It isn’t random but it is fairly arbitrary and comes from the mists of time. It could have been defined differently.
There is no reason that two numbers like this should have an integer ratio. It could be on some planets the number of days in a year is a prime number and nothing will divide by it evenly. We have 12 months and they aren’t even the same number of days each because 365/12 isn’t an integer.

What if we introduce a new coin into the American system, let’s call it the Tom. And a Tom is 6 cents. So if I want to pay for something which costs 30 cents I could pay using 5 Toms. If something costs a dollar then I can’t pay for it exactly in Toms because 100/6 is not an integer so you could argue it’s not that useful a coin, but it could exist and you could use it. It doesn’t break the whole concept of American money or mean dollars can’t exist.

[Edgar Alan Hoe]

Tom is messing with us, he knows full well what he's saying is nonsense but he obviously gets a kick out of the confusion he causes.

I'm not feeding this particular troll anymore.

[AATW]

Tom is messing with us, he knows full well what he's saying is nonsense but he obviously gets a kick out of the confusion he causes.

I'm not feeding this particular troll anymore.

I have wondered this. He's either pretty dumb or pretty clever and playing us. I honestly can't work out which.
But his lack of understanding of lots of areas of maths and science is pretty poor - and, strangely, coupled with an unshakeable confidence in his understanding of them.
Odd. Or, as you say, possibly he's just trolling. Hard to tell.

[Tumeni]

Gary, the earth rotates 24 hours in relation to the sun. The earth rotates slightly slower in relation to the stars. Why do the stars matter?

.. because they form (essentially) a stationary reference point outwith our solar system

[Macarios]

There is precession in Earth's orbit, hence the difference between Sidereal year and Tropical year.

Sidereal year is time for 360 degrees around Sun.
It is 31 558 149.5 seconds.
You can measure it, for example, when Earth takes the same position between Sun and, say, Bode's Galaxy (M81), at 12 million light years.

Solar year is between consequent repetition of the same orbital event, like equinox, or solstice.
On average it is 31 556 925 secons.
As you can see, the difference is 1224.5 seconds (20 min 24.5 sec).

Sidereal day is time between consequent facing of the same meridian towards the same distant star, or, for example, the same Bode's Galaxy.
It is 86 164.1 second.

Solar day is the time between consequent facing of the same meridian towards Sun.
We defined our day and hour by that.
On average it is 86400 seconds.

Additionally:

Tropical year varies due to gravitational influence of other planets.
Planets and Moon wobble Earth in orbit, Jupiter even wobbles Sun.
Here is the variation of Tropical year from 1900 to 2099:
https://www.timeanddate.com/astronomy/tropicalyearlength.html

Solar day varies plus or minus 29 seconds, depending on Earth's orbital speed variations, explained by Kepler's Second Law.
We still use Solar day to count our calendars, not Sidereal day.
That's because what synchronizes our lives is Sun, not distant stars.
(Unless our superstition makes us believe in astrology.)

So, what would be the most convenient for us:
1. Whole number of sidereal days in sidereal year?
2. Whole number of sidereal days in tropical year?
3. Whole number of solar days in sidereal year?
4. Whole number of solar days in tropical year?

The number 4, ofcourse, but we don't have either.

All we can do is count our days and organize them into our calendar years the best we can,
to follow seasonal markers (solstices and equinoxes) as close as possible.
The closest way was Gregorian calendar.
For now it is close enough.

[Macarios]

Gary, the earth rotates 24 hours in relation to the sun. The earth rotates slightly slower in relation to the stars. Why do the stars matter?

The Earth doesn't rotate slower towards the stars, it faces same distant star 4 minutes earlier than it faces Sun, because of one day movement along the orbit.
They matter to show that "360 degrees" and "one solar day" are not the same thing.

[Macarios]

Tom is messing with us, he knows full well what he's saying is nonsense but he obviously gets a kick out of the confusion he causes.

I'm not feeding this particular troll anymore.

Our personalities are not important here.
Only facts and figures.
And it doesn't depend on Tom's or anyone else's "trolling" or "lack of understanding".

If he's trolling then it's easy: no reason to worry about his mental abilities.
If he doesn't understand, try to simplify and help him.
If you can.

In both cases, it is important for other readers to understand as well.
And that doesn't depend on WHO said it, but on WHAT has been said.

[Tumeni]

It is not merely arbitrary that the number of hours in a day should fit into the number of days in a year.

No, the number of HOURS in a day should fit the number of HOURS in a year. There's no requirement for the number of days to fit, for, as you keep saying, a year is 365.24 days. The clue that this is not a multiple of 24 is in that 0.24 that's additional to the 365.

(1 Dollar = 4 Quarters
1 Quarter = 25 Cents

So ....  4/25 = ... what?)

As I described earlier, the first number needs to be the larger one and the greatest hierarchical unit in the scenario.

so ...

9 dollars = 36 quarters
1 quarter = 25 cents

36/25 = 1.44

10 dollars = 40 quarters
1 quarter = 25 cents

40/25 = 1.60

A visualization.

The sun travels across the earth's surface each day.
Earth circumference = 24,901 mi. In 1 Day the sun travels over 24,901 mi. of earth.
24,901 / 24 = 1037.54166667 miles. Over 1 hour the sun travels over 1037.54166667 miles
After 365 days: 24,901 mi. x 365 days = 9088865 miles
After 365.24  days: 24901 x 365.24 = 9094841.24 miles
Difference = 5976.24 miles

5976.24 miles / 1037.54166667 miles = 5.76. The hours in miles fits into the difference by 5.76 times. Where are those extra hours coming from? The sun will not be in the same place.

This visualisation fails because it takes no account of axial tilt and oblateness of the Earth, and because it takes no account of the movement of Earth in its orbit. The sun travels a greater distance in the sky than the circumference, because once the Earth has moved on in its orbit, it needs to rotate more than one circumference to place the sun in the same position. Back to that diagram above showing how you need a reference point outwith the solar system to show this (reply #135, and the wikipedia that I quoted around page 2 or 3 ....)

[Macarios]

Tie motorized model of airplane to a rope and let it fly around some pole.
Why the propeller doesn't turn the whole number of times during one revolution around the pole?

----------------------------------------------------

What we count is not Tropical year, nor Sidereal year.
We count Calendar year.

[Tumeni]

Lets try to do the math on this hunch you have.

By all means, let us do that. Then we can explore how condescending this comment is, when your basis for this whole thread is a big 'hunch' ....

Seriously, there is not ONE comment in this thread that I can find that agrees with you. Nobody supports your position. Nobody agrees with your calculations. Every comment from everyone who is not you either questions your premise, or explicitly disagrees with your figures.

What does this tell you?

[Devils Advocate]

Nobody supports your position.

To be honest it's not even clear what Tom's position is anymore, he's been digging himself into a hole so deep it's all gone dark and the lack of Oxygen is doing strange things to him...

[AATW]

To be honest it's not even clear what Tom's position is anymore, he's been digging himself into a hole so deep it's all gone dark and the lack of Oxygen is doing strange things to him...

Honestly no idea why he things the number of days in a year (which is defined as the number of times the earth rotates as it makes one orbit of the sun, and isn't actually an integer a value itself) and the number of hours in a day (which is defined arbitrarily based on a system the ancient Egyptians made up and could easily be defined a different way) should have an integer ratio.
It's this which makes me think he might be trolling, but agree with Macarios that even if he is other people will see and understand the arguments for what they are.

[AATW]

In sort of related news:

According to Rubeus Hagrid...
A Galleon is made up of 17 Sickles and
A Sickle is made up of 29 Knuts.

http://harrypotter.wikia.com/wiki/Wizarding_currency

But wait...29/17 isn't an integer, nor is 17/29. Help!

It's almost like JK made up some numbers. BUT...that currency system would work. It would be a bit inconvenient to work with but you could use it.

[douglips]

When you multiply you get the same issue. (7 days*24 hours)=168 hours/wk. (24 hours*24 hours)=576 hours. Sure they're both ostensibly in hours, but you've still go that 'wk' bit technically. You can't do anything with the pair of them that means anything.

Again, your claim is that x solar rotations, must go evenly into 1 orbital cycle. Unfortunately, you're just incorrect. They have no required correlation.

24 hours * 24 hours = 576 hours^2.
24 days * 24 hours/day = 576 hours.