it's the one that makes the Earth's rotation slow down so it fits in with those way-too-accurate atomic tick-tock thingies.
it's the one that makes the Earth's rotation slow down
They said something like that on the news when Japan had that deadly earthquake, tsunami, and nuclear disaster a few short years ago, something about the earths rotation and then how it self-corrected itself.
SMH
It's not the science that changes; the calculation for an ellipsis' circumference (such as a planet's orbit or rotation) is based on Pi. As we are more and more capable of calculating that constant, to further decimal places, the hard set 365days which last 24hour is found to be wrong, thus we must often (every four years add a day, every so often add a second) adjust to correct the "o'clock" so we dont have to retrain our entire species of what time is.
Think of these seconds as the remainders of every day not being an exact 24 rotational hours and/or each year not being an exact 365 day orbit. If we did not do these "leaps" and "falls" of time the seasons would slowly migrate along the year throughout decades/centuries/millennia.
https://en.wikipedia.org/wiki/Leap_year
Here's a cool quote about calculating elliptical circumferences
Meaning we can only, educatedly, guess at how many "seconds" (points on a round shape) it takes to go around the sun, and every so often science (no quotes) adjusts (not "gets it wrong" per se).There is no simple formula with high accuracy for calculating circumference of an ellipse.