Question

In the simplified version of Kepler's third law, P 2 = a3, the units of the orbital period P and the semimajor axis a of the ellipses must be, respectively, ___________ and ____________

Answer 1

The units of the orbital period P is years and the units of the semimajor axis a is astronomical units.

Step-by-step explanation:

P² = a³ is the simplified version of Kepler's third law which governs the orbital motion of large bodies that orbit around a star. The orbit of each planet is an ellipse with the star at the focal point.

Therefore, if you square the year of each planet and divide it by the distance that it is from the star, you will get the same number for all the other planets.

Thus, the units of the orbital period P is years and the units of the semimajor axis a is astronomical units.