Imagine we've discovered a planet orbiting another star at 1 AU every 6 months.The planet has a moon that orbits the planet at the same distance as our Moon,but it takes 2 months.What can we infer about this planet?
A)It is more massive than Earth.
B)It is less massive than Earth.
C)It has the same mass as Earth.
D)We cannot answer the question without knowing the mass of the star.
E)We cannot answer the question without knowing the mass of the moon.

Question

Quizplus · Accepted Answer

The planet has the same orbital distance as Earth, but it completes one orbit around its star in six months, which means it moves at a faster rate. Therefore, the planet has to be less massive than Earth to achieve this orbit. Furthermore, the moon's orbital distance is the same as our Moon’s, but it takes only two months to complete one cycle, indicating a lighter planet as it has less gravitational force to hold the moon in its orbit.

Imagine We've Discovered a Planet Orbiting Another Star at 1