Question

In Ptolemy’s Earth-centered model for the solar system, Venus’s phase is never full as viewed from Earth because it always lies between Earth and the Sun. In reality, as Galileo first recognized, Venus is __________.

a. full whenever it lies directly between Earth and the Sun.
b. full whenever it is on the opposite side of the Sun from Earth, although we cannot see the full Venus because it is close to the Sun in the sky.
c. never full because Earth's shadow falls on Venus at the time when it would otherwise be full.
d. never full because the sunlit side of Venus never faces directly toward Earth.

Answer 1

The correct answer is B - full whenever it is on the opposite side of the Sun from Earth, although we cannot see the full Venus because it is close to the Sun in the sky.