Halley’s comet orbits the Sun with a period of 76.2 years.

Question

a) Find the semi-major axis of the orbit of Halley’s comet in astronomical units (1 AU is equal to the semi-major axis of the Earth’s orbit

Physics - drwls, Thursday, May 5, 2011 at 8:51am
There is a simple form of Kepler's Third law for objects orbiting the sun.

If the period P is in years and the semimajor axis a is in a.u.,

P^2 = a^3

You know that P = 76.2 yr

Solve for a

Thanks a lot, I'm confused with part b as well...
If Halley’s comet is 0.56 AU from the Sun at perihelion, what is the maximum distance from the Sun, and what is the eccentricity of its orbit?

Answer 1

.59 AU