What Makes Up Our Solar System? Asteroids

Planets are not the only things orbiting the Sun , there are other smaller objects to consider, such as other dwarf planets, asteroids, comets, and meteoroids. In this article, you will learn about asteroids and some of the characteristics of this celestial object.


Asteroids (also known as minor planets) are comprised of rocky or metallic matter. The majority of the objects orbit the Sun in the asteroid belt located between Mars and Jupiter. The asteroid belt is home to about 40,000 known asteroids. Asteroids vary in size. Some are as small as a tiny pepper, while others measure up to 578 miles (930 kilometers) in diameter. A handful of asteroids are so big, they have their own orbiting moons. Astronomers have catalogued around 3,000 asteroids. Altogether, there are many other smaller asteroids in existence. The first asteroid discovered and recorded was Ceres. Recognized as the largest, it was found in 1801.

What is the Asteroid Belt?

The concentration of asteroids that orbit the Sun between the orbits of Mars and Jupiter is called the asteroid belt , which is shaped like a doughnut. The majority of asteroids orbit from between 186 million to 370 million miles from the Sun. The asteroids found in the asteroid belt have a slightly elliptical orbit. It takes anywhere from 3 to 6 Earth years for an asteroid to make one revolution around the Sun. The asteroid belt is affected by the powerful gravitational force of Jupiter, which pulls the asteroids away from the Sun and prevents them from making contact with the inner planets.

Ceres , the Biggest Asteroid

When it comes to taking honors for being the largest asteroid, look no farther than Ceres. It was an Italian astronomer named Giuseppe Piazzi who found Ceres on January 1, 1801, making it the first asteroid ever discovered. To get a perspective of how large Ceres is, imagine an asteroid the same size as the state of Texas. When compared to other asteroids, its size is incredibly massive. Measuring around 578 miles in diameter, Ceres has been given the title of being a dwarf planet.

The Naming of Asteroids  

Symbols , When the first couple of asteroids were discovered, they were given symbols similar to the ones that traditionally identify Earth, the Moon, Sun, and other planets. Over time, it became a burden to draw the symbols, and many people had a hard time recognizing what they stood for. By the end of 1851, there were 15 known asteroids, and with the exception of one, they all had their own symbol.

Naming of an Asteroid , When a new asteroid is discovered, it is given what is called a provisional designation, which consists of the year it was found and “an alphanumeric code indicating the half-month of discovery and the sequence within that half-month.” An example of this designation is 2002 AT4. After confirming the orbit of an asteroid, it is assigned a number, and sometimes given a name, such as 721 Pithos. At times, it is common to see the number dropped from the name.