Bill Nye the Science Guy - Season 4 - Eps 20: Time
Time affects every living thing on Earth. Trees shed their leaves. Some animals only come out at night. There are even insects that only emerge every 17 years. Days, hours, minutes, and seconds – all of these were invented by humans. Humans came up with these units of time to organize their lives and to study the world. One of the first ways humans told time was by noticing the difference between daytime and nighttime. Humans use the Earth revolving around the Sun to divide time into years and seasons. Months are based on the movement of the Moon around the Earth. A day is when the Earth spins completely around its own axis.
About Bill Nye the Science Guy

Title: Bill Nye the Science Guy
First Air Date: 1993-09-10
Last Air Date: 1998-06-20
Status: Ended
Rating: 7.2/10 (from 80 votes)
Language: EN
Seasons: 6
Total Episodes: 100
Network: PBS
Genres: Comedy, Documentary, Kids
Production Companies: Rabbit Ears Productions, KCTS Television
Synopsis
It's "Mr. Wizard" for a different decade. Bill Nye is the Science Guy, a host who's hooked on experimenting and explaining. Picking one topic per show (like the human heart or electricity), Nye gets creative with teaching kids and adults alike the nuances of science.
Cast

Bill Nye
Self - Host

Rachel Glenn
Nancy

Jennifer Lin

Amy Broder
Amy

Ethan Ferkiss
Smell Gibson