GENERAL KNOWLEDGE

Detailed explanation-1: -The planets Mercury, Venus, Earth, and Mars, are called terrestrial because they have a compact, rocky surface like Earth’s terra firma. The terrestrial planets are the four innermost planets in the solar system.

Detailed explanation-2: -The four rocky planets are Mercury, Venus, Earth and Mars. They are the closest four planets to the Sun. They are made of rocks and metals. They have a solid surface and a core which is mainly made of iron.

Detailed explanation-3: -The four planets that are more distant from the sun-Jupiter, Saturn, Uranus, and Neptune-are called gas giants. Gas giants are huge compared with Earth, and they do not have solid surfaces. They are big balls of gas. Jupiter and Saturn are composed mostly of hydrogen and helium.