なぜ一年は 365.242199 日あるのでしょうか?
Why are there 365.242199 days in a year?
Why are there 365.24 days in a "Year"? (In Layman's Terms, Short Version)
Part 2 (rough): Why are there 365.24 days in a "Year"? (In Layman's Terms, Long Version)
Why LEAP YEAR Occurs?
@365.24days
leap year 2012
Earth Revolution
Who decided 365 days in a year?
Longest Day/Night in Tokyo, Japan (21 June, 21 December)
An Year On Earth Isn't Just 365 Days
Longest Day/Night in Zurich, Switzerland (21 June, 21 December)
Is a year exactly 365.25 days?
Longest Day/Night in New York, USA (21 June, 21 December)
[Calendar] 2-3 The Difference Between a Lunar Twelvemonth and a Solar Year
Organizing Dates with an Ancient Egyptian Calendar ,Why Are There 365 Days in a Year?
Agriculture 365 Days a Year
Does a year have 365.25 days?
Why Does a Year Have 365 Days and 6 Hours? Explained in Simple Terms.#neildegrassetyson
How many days in a year.
