Most of the asteroids in the Solar System orbit the Sun in a band between Mars and Jupiter. This band is nearly 550 million km (340 million miles) wide and is called the asteroid belt. There are billions of asteroids in this zone, each moving independently around the Sun and spaced many thousands of kilo-metres from each other.
The asteroid belt is located between the inner and the outer planets and is home to thousands of rocks and debris known as asteroids and some of the dwarf planets. All of these orbit the Sun.
Some asteroids do orbit in space near to Earth and some are forced out of the asteroid belt by gravity and sent towards the outer solar system instead. There are hundreds of thousands of asteroids in the asteroid belt, but almost half of the entire mass is made up of just four objects. These objects are the dwarf planet Ceres, and three other asteroids called Vesta, Pallas and Hygiea. The diameters of Vesta, Pallas and Hygiea are over 400km and Ceres is even bigger at 950km diameter.
Of the many thousands of asteroids in the asteroid belt, Ceres is the only one large enough to be classified as a “dwarf planet”. Apart from these four objects, the remaining objects in the asteroid belt range in size from small rocks right down to dust particles.
The asteroid belt is between the planets Mars and Jupiter. It is located about 2.2 to 3.2 Astronomical Units (AU) from the Sun. That is somewhere between 329-478 million km away. The asteroid belt is huge and the space between each of the asteroids is over 600,000 miles. The circumference of Earth is only 24,901.45 miles, which means that the distance between objects in the asteroid belt is more than 24 times the circumference of Earth.