What is the structure of the planets in our solar system?

Solar System Structure. Our solar system consists of one smallish star (the Sun), eight planets, a few billion asteroids and a few more billion comets. Add to that masses of dust and gas, and there you have it. Planets. Close to the Sun we have four small, rocky planets – Mercury, Venus, Earth and Mars. read more

Solar System Structure. Our solar system consists of one smallish star (the Sun), eight planets, a few billion asteroids and a few more billion comets. Add to that masses of dust and gas, and there you have it. Close to the Sun we have four small, rocky planets – Mercury, Venus, Earth and Mars. read more

Among the terrestrial planets, Earth and Venus have experienced the most geological activity over their histories, although some of the moons in the outer solar system are also surprisingly active. In contrast, our own Moon is a dead world where geological activity ceased billions of years ago. read more

Solar System Structure Our solar system consists of one smallish star (the Sun), eight planets, a few billion asteroids and a few more billion comets. Add to that masses of dust and gas, and there you have it. read more

Chemically and structurally, Earth’s Moon is like the terrestrial planets, but most moons are in the outer solar system, and they have compositions similar to the cores of the giant planets around which they orbit. read more