What is an Asteroid?

About Asteroid

• Asteroids, sometimes calledminor planets, are rocky remnants left over from the earlyformation of our solar system about 4.6 billion years ago.
• The current known asteroid count is at least 1,351,400.
• Most of this ancient space rubble can be found orbiting the Sun between Mars and Jupiter within the main asteroid belt.
• Asteroids orbit the sun in highly flattened, or "elliptical" circles, often rotating erratically, tumbling, and falling through space. 
• Asteroids range in size from Vesta, the largest at about 329 miles (530 kilometers) in diameter, to bodies that are less than 33 feet (10 meters) across. 
• Asteroids come in a variety of shapes, from near spheres to irregular double-lobed peanut-shaped asteroids.
• The total mass of all the asteroids combined is less than that of Earth's Moon.
• Many large asteroids have one or more small companion moons. An example of this is Didymos, a half-mile (780 meters) wide asteroid that is orbited by the moonlet Dimorphos, which measures just 525 feet (160 m) across.

Q1: What is a Comet?

A comet is a celestial object composed of ice, dust, rock, and various volatile compounds that orbits the Sun in an elongated or elliptical path. When comets approach the Sun, they heat up and release gas and dust in the form of a glowing coma (a diffuse, bright area around the nucleus) and often exhibit a tail that points away from the Sun due to the solar wind and radiation pressure.