Why Some Days Aren’t 24 Hours

In the future, aliens contact Earth but struggle to understand the concept of a day. Initially, a day is explained as Earth's rotation, leading to confusion with stellar days. A solar day is then described, highlighting its variability due to Earth's orbit and axial tilt. Finally, a standard 24-hour day is defined using cesium atom oscillations. An interactive video is recommended for further exploration of these concepts.

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