Solar system, assemblage consisting of the Sun and those bodies orbiting it: 8 planets with more than 400 known planetary satellites; many asteroids, some with their own satellites; comets and other icy bodies; and vast reaches of highly tenuous gas and dust known as the interplanetary medium.
What is in the Solar System?
The solar system includes the Sun and everything that orbits it: planets, dwarf planets, moons, rings, asteroids, comets, and particles of dust. The solar system model is being updated by spacecraft like New Horizons. July 2025: What's up in the sky? The solar system is located in one of the spiral arms of the Milky Way galaxy.
There are a few main parts of the Solar System. Here they are in order from the Sun, with the planets numbered, and dwarf planets marked with letters. The inner planets. From left to right: Mercury, Venus, Earth, and Mars
Any natural solar system object other than the Sun, a planet, a dwarf planet, or a moon is called a small body; these include asteroids, meteoroids, and comets. Most of the more than one million asteroids, or minor planets, orbit between Mars and Jupiter in a nearly flat ring called the asteroid belt.
The Solar System possesses several distinctive features that set it apart from other star systems and celestial structures in the universe. These characteristics include: Central Star: The Sun, a yellow dwarf star of spectral type G2V. Sun's Size: Approximately 1.4 million kilometers in diameter (109 times the diameter of Earth).
So far, Earth is the only place we've found life in our solar system. Our solar system includes the Sun, eight planets, five officially named dwarf planets, hundreds of moons, and thousands of asteroids and comets. Our solar system is located in the Milky Way, a barred spiral galaxy with two major arms, and two minor arms.
Minor bodies in the Solar System include all objects that are neither planets, dwarf planets, nor moons. These include: Asteroids – Also called "small planets," they primarily reside in the Asteroid Belt between Mars and Jupiter. Meteoroids – Smaller fragments of asteroids or comets that can enter Earth's atmosphere as meteors.