Halley's Comet returns to the Sun's vicinity every 76 years in an elliptical orbit. What is the semimajor axis of this orbit?

Question

Quizplus · Accepted Answer

The semimajor axis of an orbit can be calculated using Kepler's Third Law, which relates the orbital period (in years) to the semimajor axis (in astronomical units, au) of its orbit around the Sun. For Halley's Comet, with an orbital period of approximately 76 years, the semimajor axis is about 17.5 au.

Halley's Comet Returns to the Sun's Vicinity Every 76 Years