Question

ess investigation - unearthing mars, student answer packet 2

1. describe how the location and motions of the planets in our solar system are governed by each of keplers three laws.

law 1:

law 2:

law 3:

Explanation:

• Law 1 (Orbit Law): Planets move in elliptical orbits with the Sun at one focus. This determines their orbital paths (location aspect).
• Law 2 (Area Law): A line segment joining a planet and the Sun sweeps out equal areas during equal intervals of time. This governs the speed (motion aspect) - planets move faster when closer to the Sun and slower when farther.
• Law 3 (Harmonic Law): The square of the orbital period ($T$) of a planet is proportional to the cube of the semi - major axis ($a$) of its orbit ($T^{2}\propto a^{3}$). This relates the time it takes a planet to complete an orbit (motion - orbital period) with its average distance from the Sun (location - semi - major axis).

Answer:

• Law 1: Planets orbit the Sun in elliptical paths (with the Sun at one focus), defining their orbital locations.
• Law 2: Planets' orbital speeds vary such that a line from the planet to the Sun sweeps equal areas in equal times (governing motion - speed).
• Law 3: $T^{2}\propto a^{3}$ (relating orbital period (motion) and semi - major axis (location)).