As seen from Earth, which planets in the Solar System have a wide range of phases? Please explain the reason.

Question

As seen from Earth, which planets in the Solar System have a wide range of phases? Please explain the reason.

Answer 1

Mercury and Venus exhibit almost the entire range of phases. Because they pass between Earth and Sun, we may see them as very thin crescents at that time (like the Moon). For the rest of the planets, being further from the Sun than Earth is, their visible disks are more than half illuminated at all times.