Terrestrial planets, also known as rocky planets, are a group of planets in our solar system that are similar in structure to Earth. The four terrestrial planets are Mercury, Venus, Earth, and Mars. These planets are characterized by their solid, rocky surfaces and relatively high densities compared to the gas giants, which are the other type of planets in the solar system.
Let's take a closer look at each of the terrestrial planets:
Planet | Diameter (km) | Distance from Sun (million km) | Atmosphere Composition |
---|---|---|---|
Mercury | 4,880 | 57.9 | Very thin exosphere |
Venus | 12,104 | 108.2 | Carbon dioxide (96%) and nitrogen (3.5%) |
Earth | 12,742 | 149.6 | Nitrogen (78%), oxygen (21%), argon (0.9%) |
Mars | 6,779 | 227.9 | Carbon dioxide (95.3%), nitrogen (2.7%), argon (1.6%) |
Studying the terrestrial planets provides valuable insights into the formation and evolution of rocky bodies in our solar system and beyond. Understanding the similarities and differences among these planets helps scientists unravel the processes that shaped our own planet and the potential for habitability on other rocky worlds.