What is a Leap Year?

Why do some years have an extra leap day and what is it for?
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Also check out MinutePhysics' video: http://www.youtube.com/watch?v=53glKE... & SciShow: http://www.youtube.com/watch?v=HnDsXh...

• Category

  Education

[xsTroNgeR1]

Creeper in car at 1:38

[Brenden Stevens]

lol where dead in like 4000 years, unless nasa has half a brain.

[GunsOfThePhoenix]

Starcraft Protoss HUD at 0:37 xD

[Kris Kahle]

thumbs up for minute physics leading you here

[Daniel Kim]

i think he means the little creature at 3:05 in the bottom left corner

[Numa Rake]

...So how many day/night cycles does it take for the sun to rise again behind that ONE position? A year. xD Anyways, my best guess at how we did it. It may not seem so obvious as a whole, but looked at step by step, it's simple, logical and IT DOES NOT REQUIRE ALIENS...wich seems to be the answer nowadays for every single Human accomplishment. My two cents.

[Numa Rake]

Epic leghts of time spent stargazing. xD Let's say you got tired of chasing game, settled and alas, got bored. You have around you landmarks you know perfectly well. Inquring mind as you are, you notice the sun rises from behind one of those landmarks today, but surprisingly after a few weeks it has apparently moved. You start looking at it everyday. A pattern might emerge, and after a while, it will rise behind that same landmark. Weird, let's take notes of this...

[Ben Wells]

Starcraft map:D 0:36

[NimbusSpectrum]

1:20. Luna and Celestia's cutie marks /)

[dunskatorpeda]

"the obvious way to keep track of their comings and goings is to count the days passing, which gives you a 365 day calendar." it doesnt seem obvious to me, how exactly do you know when to stop counting? i mean how do you know when its starting to repeat? by measuring the lengths of consecutive nights and counting how many days have passed since one summer solstice to the next one? haha have i answered myself?