ICOT- its not a full 24 hours because the Earth does not pass by the sun at equal points throughout the year. We say a rotation is from high-noon to high-noon the next day but the two days are of different lengths! That is why we have a leap year- to make up for all the different time frames and make them equal the time it takes for “a year”- full rotation about the sun. To explain it better,I looked it up…I was not able to say it quite as well… here is from someone with a PHD in science… “The time for one true rotation is the interval between the times that a distant star is highest in the sky, “fixed star to fixed star.” This interval is known as a “sidereal” day, which is 23 hours, 56 minutes, 4.06 seconds.”
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