2007-03-01 04:08:59 · 5 answers · asked by Anonymous in Arts & Humanities ➔ History
The folks who figured out how to keep the calendar straight by using an extra day every four years realized that this formula still needed correction, so the 00 years were eliminated unless they were divisible by 400. The year is 365.2425 days long.
2007-03-01 04:19:48 · answer #1 · answered by Duane R-H 2 · 4⤊ 0⤋
The calendar has to keep up with how the earth orbits around the sun. One revolution around the sun is not exactly 365 days, it isn't even 365 and 1/4 days (which is why every 4th year is a leap year -- to keep the calendar correct).
Because it is "off" of 365 and 1/4 days by a small fraction, the calendar is "off" by one day about every 100 years.
Julius Ceasar (the Roman emperor) figured out the basic calendar 2000 years ago, but it was off, so Pope Gregory (and his astronomers) worked out the new calendar which skips leap years every 100 years, or something like that... the link explains the whole thing in detail.
http://www.infoplease.com/spot/gregorian1.html
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2007-03-01 04:16:54 · answer #2 · answered by tlbs101 7 · 3⤊ 0⤋
Because we 'add' that 'extra day in February' to keep the 'seasons' coming at the same approximate time every year, but on certain years we don't 'add' it to help 'even it out' over time. In other words, 1900 and 2100 aren't 'leap years' because those are the years 'chosen' for us not to add a February 29 to help 'even the seasons out' again.
2007-03-01 04:15:27 · answer #3 · answered by Kris L 7 · 2⤊ 1⤋
Leap years occur once every four years. Therefore, not every year that ends in '00' will be a leap year.
2007-03-01 04:14:34 · answer #4 · answered by Holiday Magic 7 · 0⤊ 2⤋
Who says they aren't? That's something new I learnt. Thanks. Looking forward to the answer.
2007-03-01 04:14:26 · answer #5 · answered by Anonymous · 0⤊ 1⤋