In order to explain the varying speed of the planets across the night sky,Ptolemy's model introduced:
A) elliptical orbits.
B) the equant.
C) the celestial sphere.
D) synodic months.

Question

Quizplus · Accepted Answer

Ptolemy's model introduced the equant to explain the varying speed of the planets across the night sky. The equant is a point in space that is opposite the Earth from the center of the planet's orbit, and the planet moves at a uniform speed around this point.

In Order to Explain the Varying Speed of the Planets