Editing Talk:1514: PermaCal

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Not unrelated concept. Just not fully understood. Rotate 360 degrees is a simple way of putting things that ignores the diffrence between solar days and sidereal days. Incorrect not because someone doesn't understand the topic being discussed but because someone hasn't studied astronomy or seriously thought about how the movement of the Earth effects the length of the day--[[Special:Contributions/108.162.237.183|108.162.237.183]] 13:00, 20 April 2015 (UTC).
 
Not unrelated concept. Just not fully understood. Rotate 360 degrees is a simple way of putting things that ignores the diffrence between solar days and sidereal days. Incorrect not because someone doesn't understand the topic being discussed but because someone hasn't studied astronomy or seriously thought about how the movement of the Earth effects the length of the day--[[Special:Contributions/108.162.237.183|108.162.237.183]] 13:00, 20 April 2015 (UTC).
 
:Guilty.  No excuse either, because I actually knew (but just forgot) about the difference between sidereal and solar days. [[Special:Contributions/108.162.249.162|108.162.249.162]] 01:14, 21 April 2015 (UTC)
 
:Guilty.  No excuse either, because I actually knew (but just forgot) about the difference between sidereal and solar days. [[Special:Contributions/108.162.249.162|108.162.249.162]] 01:14, 21 April 2015 (UTC)
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There is some confusion between the different types of astronomical time:  a day in mean solar time is 24 hours, with a difference of + or - up to 1 second (compared to time on an atomic clock), in apparent solar time is 24 hours + or - up to 30 seconds, and in mean sidereal time is 23 hours, 56 minutes, 4.0916 seconds (according to Wikipedia), and there is one extra sidereal day (about 366.25) in a sidereal year. [[User:The Dining Logician|The Dining Logician]] ([[User talk:The Dining Logician|talk]]) 13:55, 20 April 2015 (UTC)
  
 
While you are true on one part, that Earth doesn't take 24 hours to rotate 360 degrees (it takes around 23 hours and 56 minutes if I recall correctly), leap seconds are used to account for differences between 24 hours and a solar day. If it was used to adjust the length of the year the time of day would drift, it would also be fairly pointless as the leap days take us out by 1/4 of a day.[[Special:Contributions/108.162.250.175|108.162.250.175]] 10:41, 20 April 2015 (UTC)
 
While you are true on one part, that Earth doesn't take 24 hours to rotate 360 degrees (it takes around 23 hours and 56 minutes if I recall correctly), leap seconds are used to account for differences between 24 hours and a solar day. If it was used to adjust the length of the year the time of day would drift, it would also be fairly pointless as the leap days take us out by 1/4 of a day.[[Special:Contributions/108.162.250.175|108.162.250.175]] 10:41, 20 April 2015 (UTC)
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:The archive claims that it was released on the 20th.--[[User:17jiangz1|17jiangz1]] ([[User talk:17jiangz1|talk]]) 15:08, 20 April 2015 (UTC)
 
:The archive claims that it was released on the 20th.--[[User:17jiangz1|17jiangz1]] ([[User talk:17jiangz1|talk]]) 15:08, 20 April 2015 (UTC)
 
Apropos a "permanent calendar", Isaac Asimov proposed just such a calendar. http://calendars.wikia.com/wiki/World_Season_Calendar This web page unfortunately doesn't go into details, but there were several advantages. The same calendar is used for all years, your birthday is always on the same day of the week, no need to remember "30 days hath Sept. ...", and several other advantages I can't remember right now. --[[User:RenniePet|RenniePet]] ([[User talk:RenniePet|talk]]) 12:45, 20 April 2015 (UTC)
 
Apropos a "permanent calendar", Isaac Asimov proposed just such a calendar. http://calendars.wikia.com/wiki/World_Season_Calendar This web page unfortunately doesn't go into details, but there were several advantages. The same calendar is used for all years, your birthday is always on the same day of the week, no need to remember "30 days hath Sept. ...", and several other advantages I can't remember right now. --[[User:RenniePet|RenniePet]] ([[User talk:RenniePet|talk]]) 12:45, 20 April 2015 (UTC)
βˆ’
 
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There is some confusion between the different types of astronomical time:  a day in mean solar time is 24 hours, with a difference of + or - up to 1 second (compared to time on an atomic clock), in apparent solar time is 24 hours + or - up to 30 seconds, and in mean sidereal time is 23 hours, 56 minutes, 4.0916 seconds (according to Wikipedia), and there is one extra sidereal day (about 366.25) in a sidereal year. [[User:The Dining Logician|The Dining Logician]] ([[User talk:The Dining Logician|talk]]) 13:55, 20 April 2015 (UTC)
 
  
 
It seems like our collective favorite word just might be "portmanteau" [[User:YourLifeisaLie|The Goyim speaks]] ([[User talk:YourLifeisaLie|talk]]) 13:42, 20 April 2015 (UTC)
 
It seems like our collective favorite word just might be "portmanteau" [[User:YourLifeisaLie|The Goyim speaks]] ([[User talk:YourLifeisaLie|talk]]) 13:42, 20 April 2015 (UTC)

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