Talk:Year

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Should there be a mention that on other planets the year is different? --Daniel C. Boyer

It does seem to now: perhaps editted since your undated comment? As it looks out of date, lets agree if you do not repeat it within a month of this query I'll do a clean-up (talk)--BozMo 22:25, 9 May 2004 (UTC)

the same is here: http://www.sciencedaily.com/encyclopedia/year :P

Can some physics guru out there calculate the shorting of the year due to the mass loss of the sun over time. Because the rate is so gradual I do not expect there to be non equillibrium effects. Assuming a circular orbit, the radial orbit change(accelleration) should be able to be calculated from a force balance of the centripetal and gravitational forces. This radial change will give a new period since the kenetic and potential energy is related in orbital mechanics. I'm currious about the change in the period over time, since it has implications on the age of the earth, and the rate of energy output of the sun.

This also has an impact on the alinement of planets the ancients saw when the looked up at the sky. Does anyone know if celestia takes this into account when calculating historical star chart data?

Contents 1 Seasonal Year edit 2 Astronomical Year section reformatting 3 Calendar repetition 4 Oriental great year 5 gigayear 6 Re Gaussian Year 7 Draconic years instead of 365 day year 8 Weeks 9 orbital chaos

[edit] Seasonal Year edit

I removed "the hottest day of the year" as an example starting point for a seasonal year because it is not a definite/conclusive starting point in that there could always be a unexpected hotter day later on. All the other given examples have definite starting points, for instance when flowers start to bloom, you know that's the start of that flowers "season". I also added "the first scheduled game of a certain sport" to throw in a man-made seasonal year example into the mix. Comments?

[edit] Astronomical Year section reformatting

I added bullets to the listings of the astronomical years because I think it looks better in general and breaks up the different types for easier reading. I don't know if doing this is within Wiki-policy, anyone care to comment or take a vote on it?

[edit] Calendar repetition

I think it would be nice to have information regarding calendar repetition, that is, is there a way to tell when is this year's calendar going to be repeated? For example, 2005 is a Common year starting on Saturday. When in the future will the 2005 calendar be repeated, like August 12 will be friday and all other days will be the same week day as in 2005? When in the past was it repeated like that?

I've never heard of any such calculations, just wondering if anybody has.

You cite a wikipage that already lists the years that have identical calendars, so I gather you don't just want to know what years are identical, but how to determine them by calculation. Unfortunately, I don't know of any such calculation. I can only mention that whatever the retitions are, they must repeat on a 400-year cycle. — Joe Kress 18:54, August 12, 2005 (UTC)

All solar calendars with a leap year every four year and a 7-day-week repeat in principle every 28 years (=4x7). But a additional leap year interrupts this so-called solar cycle. Thus Gregorian calendar years 1801, 1829, 1857, 1885 began with a Thursday, like 1901, 1929, 1957, 1985 with a Tuesday. There are exactly 20871 weeks in a Gregorian 400 years cycle, so it well repeats after each full cycle. All in all, there exist only 14 calendars. 7 for common years, 7 for leap years.
--Peter 2005 12:51, 14 August 2005 (UTC)

[edit] Oriental great year

The following statement was added to the article by 71.36.34.14. I have moved it here because I have never heard of it even with my fairly extensive knowledge of Chinese astronomy and Creation myths, and no citation is given. It is doubtful that it is the source of the Western 24-hour day because the Chinese used a clock with twelve double hours, not one with 24 hours. The standard explanation for the Western 24-hour clock is that the Egyptians used 24 seasonal hours (12 daylignt and 12 nighttime).

Oriental astronomy puts the length of one Great Year at 24,000 years comprised of one ascending cycle of 12,000 years and one descending cycle of 12,000 years. Some scholars believe this may be the original basis for the current system of daily time; a 24 hour day with 12 hours of increasing light (AM) and 12 hours of increasing darkness (PM).

A citation is needed before it can be added to the article. Don't use the weasal words "some scholars". Cite which scholar or scholars.

— Joe Kress 01:00, 22 November 2006 (UTC)

[edit] gigayear

Why is gigayear redirected here if theres nothing about it? —The preceding unsigned comment was added by 195.194.178.251 (talk) 11:19, 12 January 2007 (UTC).

[edit] Re Gaussian Year

The present Wiki section on "Gaussian Year" is not adequate (the length is a result; it is not the definition).

I think it needs a "1 A.U." or equivalent, and a reference to the Sidereal Year.

The definition in http://www.kayelaby.npl.co.uk/general_physics/2_7/2_7_2.html should be reliable.

82.163.24.100 12:08, 29 January 2007 (UTC)

TP: I don't see anything factually wrong in that section; you are correct that the year length is a derived value, but this page does not imply otherwise. What exactly do you object against? —The preceding unsigned comment was added by Tom Peters (talk • contribs) 21:33, 29 January 2007 (UTC).

OK, I now see that, while the (Newtonian) gravitational constant G is a constant of the universe, the Gaussian constant is parochial and is governed by the orbit that the Earth happens to have - it could be called the Earth's Gaussian Gravitational Constant.

I still prefer the Kaye&Laby statement as a description of the Gaussian Year, but it is less direct as a definition.

I think that more people will be familiar with SI units than with Astronomers' units.

In "Calendar year", the day is the (mean) solar day, defined by light-and-dark, of 86400-plus-a-bit SI seconds (the bit represents leap seconds). The Julian Year apparently uses the same unit. The Sidereal Year is given explicitly in SI seconds.

The Gaussian Year, however, being dependent solely on the Gaussian constant which is a fixed value not dependent on SI, seems at first to be in astronomers' units; but Kaye & Laby says that astronomers' seconds are SI seconds.

So : in the Year page, I now think that, for the avoidance of doubt, it would be well :-

1. to mark every expressed duration as "mean solar days" or "SI days" or whatever it happens to be;
2. to mark all exact values with "exactly" or similar, and all approximate values with a numerical uncertainty or with "approximately" or similar (the Gaussian year could be put as "exactly 2π/k").

82.163.24.100 13:19, 30 January 2007 (UTC)

[edit] Draconic years instead of 365 day year

Much better solution would be adopting septenary 343-day year derived from draconic year defined here: http://en.wikipedia.org/wiki/Year#Draconic_year because it has nothing to do with satanic 6*6*10, and is defined as God's 7 days *7 weeks *7 seasons. God purposedly instituted draconic year in Solar System to give chance of avoiding satanic multiples in time measurements.83.19.52.107 10:24, 15 March 2007 (UTC)

A "solution" implies a problem or purpose. If the purpose is to appease the religious nutjobs, I guess 343 has its uses (until someone comes along who says 343 is satanic); if the purpose is to keep track of the seasons, better to stick with the tropical year God gave us. If God wanted us to use 343-day years, why establish a 346-day cycle and make it so far from obvious? —Tamfang 05:35, 3 April 2007 (UTC)

A comprehensive proof of evilness of these unholy numbers such as 6,60,90,180,270,360,666,3600,6666, which refuses to be completed up to multiples of holy seven is placed here: [1] Thus better use purely septenary system. Both draconitic and tropical year are not ideal 360 and 343 days, but their approximations such as 365.24218967 and 346.620075883 days. That proves that God provided us possibility of choosing between blessing and curse (Deuteronomy 30:19), namely between God's 343-day septenary year and between devil's 360-day sexagesimal year. 346 excess above 343 by 3 days, and 365 excess above 360 by 5 days, making draconic year closer to God's 7*7*7=343, than tropical year to devil's 6*6*10=360. More about full septimalization of all units here: [2] Only pharisee can apply satanic etiquette to God's 7*7*7=343. 83.19.52.107 08:21, 10 April 2007 (UTC)

Are honeybees satanic too, with their hexagonal cells? —Tamfang 21:51, 3 May 2007 (UTC)

Honeybees are domestified wasps, and all dangerous animals came after original sin. Before original sin they yet didn't existed. 83.19.52.107 07:52, 23 May 2007 (UTC)

[edit] Weeks

The article states that the Julian calender has 365.25 days per year but something is not right. How can there be 52 weeks in a year times seven days a week which equals 364 days? Is it safe to conclude that there are really 52.xxx weeks in a year, but we just round down to make it an even number ? —Preceding unsigned comment added by 70.17.198.177 (talk) 06:47, 18 February 2008 (UTC)

Anyone who states that there are 52 weeks in a year is not being precise. The Julian year has either 365 or 366 days thus 52 weeks and either one or two extra days beyond that number of whole weeks. But these two values mean that a single value for the number of weeks in a year (52.xxx) is possible only as an average value. — Joe Kress (talk) 08:33, 19 February 2008 (UTC)

[edit] orbital chaos

The Earth orbit varies by a chaotic way, but in a interval quite more reduiced than the orbits of the nearest planets.

What does this mean? —Tamfang (talk) 06:26, 20 May 2008 (UTC)

Can you please tell us where in the article that text is? Karl (talk) 10:24, 20 May 2008 (UTC)

Search the article for the word 'chaotic': it's in Year#Variation_in_the_length_of_the_year_and_the_day. —Tamfang (talk) 22:51, 23 May 2008 (UTC)