• chaosCruiser
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    18 hours ago

    Also known as a sidereal day. Check the animation. It’s pretty cool.

    This topic also touches upon the concept of reference frames. When people say that the earth takes 24 h to make a full revolution, it’s in relation to the sun. From a universal perspective, the heliocentric reference frame moves and rotates. From the heliocentric perspective, the usual earth based reference frame also moves and rotates. Nothing is truly stationary, and measuring revolutions is impossible unless you define your frame of reference.

    If you say a full revolution takes 24 h, it’s not wrong, but it’s only true in one reference frame.