The Leap Second Explained | Space Time | PBS Digital Studios

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Every once in a while we add a second onto our days. Similar to the Leap Year, this is known as the Leap Second. But, if the Leap Year already helps us account for the offset from a calendar in days, what exactly does the Leap Second do? Check out this video for the answer!

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Hosted by Gabe Perez-Giz

[kadotoji]

We're beating the leader of kakerou with this one.

[tonyziz]

Holy crap! I didn't imagine it was so complicated to keep track of time for our daily usage thanks for enlightening me

[bigbrotheredits]

"I told you, i'd make a comeback"

[NexLab]

MY ONLY QUESTION FOR YOU IS WHY IS YOUR THEME SONG SO CATCHY I COULD LISTEN TO IT ALL DAY

[nolanwestrich]

I remember seeing a graph on leap seconds with the mouseover text "a graph documenting the war between timekeepers and time."

[average_donald_obama_joe_liker]

Baku when he realized that he could have just watch this video for 2 minutes and 21 second instead of planning for years.

[rogue]

Thank you for explaining this CORRECTLY! Every other article on the matter says leap seconds are needed because the earth is slowing down. This is WRONG. Even if the earth stopped slowing down right now, we would still have to add leap seconds at the rate of 1 every 1.5 yrs, because the way the second was defined in 1967.

[SnakesGames]

I love this channel. It's free of political bullshit and is nothing but objective hypotheses, theories, and law.

[mintcase]

Baku watched this video to make his plan

[isha]

Thanks for the informative video! I did not understand a word 😊

[Brodafaq]

This video made me wanna drop my handkerchief 1 second longer

[RandomPerson-grsz]

He's known as usogui (the lie eater)

[davidk]

Can you make a video or two about interstellar exploration?

[roninpawn]

eh... 'scuse me maam. Just one question before I go... Why doesn't the scientific community just re-calibrate the earth-second to match the current state of Earth's rotation and spin instead of inserting leap-seconds to accommodate a two-centuries out-of-date calculation? And therein save Google from having to invent the leap smear?

If I understood the video (I may very well have not), then it sounds like a lot of very smart people have done a lot of very hard work to accommodate a problem that only exists in an imagined disparity between semi-arbitrary definitions of something that is presently measurably different than the figures in use; and that we have no plausible reason to continue using. Am I missing something or are we applying duct tape solutions when we've got replacement parts in the truck?

Presuming I'm not just really confused, it raises a fun question: If we re-calibrate the earth-second to match the current spin and rotation of the Earth around the Sun, how many years would it be before we'd need our next leap-second, or better yet, a leap-second coupled with another re-calibration? I mean, if you're going to bother everyone with a leap-second, you might as well fix the broken timebase too.

[erocicTheGreat]

I think the fact that we are able to measure the earth's rotation around the sun with such accuracy is amazing, how is that done?

[joyanz]

Good information 👍🏼
Please slow down a bit when you’re talking

[OG_Solar_Edit]

We r gonna beat the perfect human with dis one 🗣️

[NecroBones]

Awesome, thanks for this! Makes perfect sense now.

[JPMonteith]

First off, Gabe - you are absolutely brilliant. Now to ask my potentially stupid question:

Has there ever been serious consideration of a base 10 system instead? Perhaps adjust the duration of a second (make it a little shorter) so we have 100 seconds each minute, 100 minutes each hour and 10 hours each day. Computer could assign the exact duration to accurately match orbital rotation periods and do away with all of these adjustments. Odds are I am missing something on why that would be a bad idea.

[zackhjorth]

For this video all you had to say was "Its a timey-wimey thing".