Asteroids and comets have several things in common, including a relatively small size as compared to planets and a lack of a viable atmosphere. Asteroids range in size from a few feet to several miles in diameter. Comets are generally smaller, with a rocky core. Both comets and asteroids don't have enough gravity to keep atmospheres.Know More
Scientists believe comets and asteroids are leftover fragments from when the solar system formed 4.5 billion years ago. Asteroids are closer to the sun, usually between the orbits of Mars and Jupiter in the asteroid belt. Comets mainly exist at the outer edge of the solar system.
Another commonality between asteroids and comets is the way the objects hurtle toward the inner solar system. Collisions with nearby objects and gravitational pulls from distant bodies push or pull asteroids and comets closer to the sun. Some of these objects get close enough to Earth to be seen with the naked eye. Both comets and asteroids pose a threat to life on Earth if they collide with the planet.
Asteroids are chunks of rock made of heavy minerals. Comets are mostly dust and ice crystals. When comets get close to the sun, particles are jettisoned behind these objects and produce a luminous tail. Asteroids don't glow when they get closer to the sun.Learn more about Comets & Asteroids
Most asteroids originate from a large area between the planets Mars and Jupiter. This area is most commonly referred to as the asteroid belt and contains more than 200 large asteroids. Some asteroids may originate from other regions in space.Full Answer >
Most meteors that enter the Earth's atmosphere are pieces of asteroids from the asteroid belt. The meteors were formed more than 4 billion years ago during what is thought to be the early stages of the solar system.Full Answer >
Although NASA hasn't calculated an average, asteroids range in size from Ceres, measuring 590 miles in diameter, to smaller ones that measure less than a half-mile across. The last near-Earth asteroid count was performed in 2013. NASA found 861 asteroids measuring more than 0.6 miles across.Full Answer >
The solar system is made up of the sun and all the planets, dwarf planets, moons, asteroids, meteoroids, comets, ice, rocks, artificial satellites and space-faring vessels. Living beings are also in the solar system, although they are only known to exist on Earth.Full Answer >