The four basics “scales” at which astronomy is studied, that of (1) the Earth-Moon system, (2) the solar system, (3) the galaxy, and (4) the universe (Fig. 1), are a common place to start an intro astronomy course. In fact, courses and textbooks are often divided into approximately four sections based on these scales.

1.
See “Supplemental” tab at TPT Online at https://doi.org/10.1119/1.5003754 for Appendices 1 and 2.

Supplementary Material

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