Inner planets

1) The Four Inner Planets of the Solar System Are Solids and Smaller in Size. Why?

• The inner planets are closer to the Sun.
• The materials which can survive in the extreme heat produced by Sun combine to form the inner planets, and most of them are metals and rocks.
• This aggregation of metals and rocks makes the inner planet smaller and rocky.

2) Why Are There Fewer or No Moons for the Inner Planets?

• The inner planets are smaller and denser than all the planets in the solar system.
• Thus they do not have enough gravitational force to attract any celestial body or a Moon. Hence they have significantly less or no moon.

3) Why Is Mars Called the ‘Red Planet’?