The majority of asteroids that scientists have formally identified reside between the orbits of Mars and Jupiter. Scientists call this wide swath of space the asteroid belt, and though it contains millions of objects, the combined size of all of the asteroids in the belt is smaller than the Earth’s moon.
Scientists estimate that about 200 asteroids in the belt exceed 60 miles in diameter. By contrast, 750,000 asteroids of about three-fifths of a mile in diameter are thought to reside among the larger ones. One of the largest objects in the asteroid belt is classified as a dwarf planet. Named Ceres, this large asteroid is thought to represent about one-third of the total mass of the asteroid belt.
Many asteroids have moons that orbit them, although none are large enough to contain an atmosphere. As far as scientists can tell, asteroids are not capable of supporting life. Occasionally, the gravity of a large planet perturbs the orbit of an asteroid. This can cause an asteroid to crash into a planet or moon. Approximately 65 million years ago, an asteroid hit the earth with enough force to kill most of the life on the planet. Scientists scan the skies for such large meteors, hoping to spot them before they impact Earth.Learn More
Comets and asteroids are both made up of rock, dust and debris. They also both travel around space in an orbit.Full Answer >
According to Yury Zaitsev, at Space Daily, an asteroid has a speed of about 55,923 miles per hour on average. Potential asteroid impacts on Earth have become a concern in recent years, with scientists suggesting the monitoring of all space objects in close proximity to the Earth.Full Answer >
The primary reason that planetary scientists study asteroids, comets and meteoroids is because it helps them to understand the early formation of the solar system. Additionally, it is important to understand what happens when asteroids or meteoroids collide with the Earth or other planets, as such events have been important factors in the history of the planet.Full Answer >
Asteroids and comets differ in composition due to where they were formed. Most asteroids are the rocky remnants of failed planets created in the inner solar system, while comets formed further out where frozen gases and liquids could not be thawed by the heat of the sun.Full Answer >