Joseph Amato: Using Astronomy to Motivate and Teach Introductory Mechanics

Joseph Amato, Dept. of Physics and Astronomy, Colgate University

Using Astronomy to Motivate and Teach Introductory Mechanics

Physics from Planet Earth (PPE) is a one-semester, calculus-based introductory course in classical mechanics intended for first year students of physics, chemistry, astronomy and engineering. Most of the core topics in mechanics are included, but many of the examples and applications are drawn from astronomy, space science, and astrophysics. The laws of physics are assigned the task of exploring the heavens – the same task addressed by Newton over 300 years ago at the birth of classical mechanics. How do we know the distance to the Moon, Sun, or other galaxies? How do we know the masses of the Earth, Sun, and other planets and stars, and why do we believe in “missing” mass? As a physics course, PPE concentrates on how we know rather than on what we know. Examples and applications include those of historical importance (the Earth-Moon distance, the Earth-Sun distance, Ptolemaic vs. Copernican models, weighing the Earth) as well as those of contemporary interest (Hubble’s Law, rocket propulsion, spacecraft gravity boosts, the Roche limit, search for extrasolar planets, orbital mechanics, pulsars, galactic rotation curves). The course has been taught successfully at Colgate for over a decade, using materials that have been developed and refined during the past 15 years. Developers of PPE are eager to enrich the course by identifying other topics in contemporary astronomy that can be adapted for the first year physics audience.