The length of a second was initially determined astronomically, using Earth's rotation. One second was defined as 1/86,400th of a solar day. As technology advanced, we realized Earth's rotation isn't perfectly constant. In 1967, the second was redefined using atomic clocks, based on the vibrations of cesium atoms. Now, it's defined by the vibrations of cesium-133 atoms, with one second equalling 9,192,631,770 oscillations. So, our precise measurement of a second has evolved from celestial observations to the incredible precision of atomic timekeeping. Credit: Encyclopædia Britannica, Inc., https://www.britannica.com/technology/atomic-clock/images-videos Animation is created by Bright Side. #brightside —————————————————————————————- Music from TheSoul Sound: https://thesoul-sound.com/ Listen to Bright Side on: Spotify – https://open.spotify.com/show/0hUkPxD34jRLrMrJux4VxV Apple Podcast – https://podcasts.apple.com/podcast/idhttps-podcasts-apple-com-podcast-bright-side/id1554898078 —————————————————————————————- Our Social Media: Facebook – https://www.facebook.com/brightside/ Instagram – https://www.instagram.com/brightside.official/ Tik Tok – https://www.tiktok.com/@brightside.official?lang=en Snapchat – https://www.snapchat.com/p/c6a1e38a-bff1-4a40-9731-2c8234ccb19f/1866144599336960 Stock materials (photos, footages and other): https://www.depositphotos.com https://www.shutterstock.com https://www.eastnews.ru —————————————————————————————- For more videos and articles visit: http://www.brightside.me

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