Question

As seen from the earth, which planet passes through phases similar to those of the moon?
A. Jupiter
B. Mars
C. Pluto
D. Venus

Answer 1

Hint: The Solar System is the gravitationally intent system of the Sun and the objects that orbit it, either directly or indirectly. There are a total eight planets in our solar system.

Complete answer: Option A. Jupiter is the largest planet. It does not show phases like the moon. This option is incorrect.
Option B. As Mars orbits the sun outside the Earth's orbit, Mars does not exhibit the whole range of phases, as our moon does. This option is incorrect.
Option C. As the Moon's spin period is the same as its orbital period around Earth, the same face of the Moon always faces the Earth. Just like our Moon, Charon's spin period is the same as its orbital period and from Pluto you only see the one side of the moon. This option is incorrect.
Option D. Apart from the Earth, Venus is the only planet which shows phases like the moon. The weather permitting, Venus is the first planet which night sky observers can spot, and it is even visible before sunset. The phases of Venus result from the planet's orbit around the Sun inside the Earth's orbit giving the observer a sequence of progressive lighting similar in appearance to the Moon's phases. It presents a full image when it is on the opposite side of the Sun. This option is correct.

Thus, The right answer is Option D.

Note: The first person to point a telescope at Venus was Galileo Galilei in 1610. It is the brightest object in the sky after the Sun and the Moon. The earth shows phases, just like the Moon does for terrestrial observers.