The inner planets (in order of distance from the sun, closest to furthest) are Mercury, Venus, Earth and Mars. After an asteroid belt comes the outer planets, Jupiter, Saturn, Uranus...

Three of the four inner planets (Venus, Earth, and Mars) have atmospheres substantial enough to generate weather; all have impact craters and tectonic surface features, such as rift valleys and volcanoes.

The four innermost planets of our solar system (Mercury, Venus, Earth and Mars) are called the “terrestrial” planets. The name comes from the word “telluric” derived from the Latin words “terra” and “tellus”, used to refer to Earth.

Inner Solar System. Planetary Science missions to the inner solar system extend mankind’s presence to the rocky worlds and help to unlock the secrets of the solar systems’ composition, history and evolution, and how life on Earth began.

The four inner planets, or terrestrial planets, have solid, rocky surfaces. Earth, the third planet from the Sun, is the only planet with large amounts of liquid water, and the only planet known to support life.

The planets of the solar system are divided into two groups: the inner planets and the outer planets. The inner planets are those closest to the sun: Mercury, Venus , Earth, and Mars. The outer planets are those farthest from the Sun: Jupiter, Saturn, Uranus, and Neptune.

These inner planets also are known as terrestrial planets because they have solid surfaces. Mercury Facts. Mercury is the smallest planet in our solar system, and the nearest to the Sun. Explore Mercury. Venus Facts. Venus is the second planet from the Sun, and Earth's closest planetary neighbor. Explore Venus.

The asteroid belt separates the inner planets and the outer planets. The Outer Planets. In order outward from the Sun, the outer planets are Jupiter, Saturn, Uranus, and Neptune. Jupiter – The largest planet, Jupiter’s radius is a staggering 69,911 km (43,441 mi), and its diameter is about 139,822 km (86,881 mi). It is 11.21 times the size ...

The inner planets are small, rocky, low on moons, and ringless, yet the outer planets are huge, gaseous, and icy, with rings and lots of moons. Find out why!