Asteroids are the rocky remnants of material leftover from the formation of the solar system and its planets approximately 4.6 billion years ago. The majority of asteroids originate from the main asteroid belt located between Mars and Jupiter, according to NASA. NASA's current asteroid count is over 1 million. Asteroids orbit the sun in highly flattened, or "elliptical" circles, often rotating erratically, tumbling and falling through space.
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. Asteroids are also often referred to as "minor planets" and can range in size from the largest known example, Vesta, which has a diameter of around 326 miles (525 kilometers), to bodies that are less than 33 feet (10 meters) across.
Vesta recently snatched the "largest asteroid title" from Ceres, which NASA now classifies as a dwarf planet. Ceres is the largest object in the main asteroid belt while Vesta is the second largest. As well as coming in a range of sizes, asteroids come in a variety of shapes from near spheres to irregular double-lobed peanut-shaped asteroids like Itokawa. Most asteroid surfaces are pitted with impact craters from collisions with other space rocks. Continue reading from Space
The asteroid belt is a region of space between the orbits of Mars and Jupiter where most of the asteroids in our Solar System are found orbiting the Sun. The asteroid belt probably contains millions of asteroids. Astronomers think that the asteroid belt is made up of material that was never able to form into a planet, or of the remains of a planet which broke apart a very long time ago. The asteroids in the asteroid belt come in a variety of sizes. Some are very small (less than a mile across), while others are quite large. The largest asteroid is called Ceres. It is about one-quarter the size of our moon. It is a dwarf planet. Continue reading from Cool Cosmos
Our solar system formed about 4.5 billion years ago from a dense cloud of interstellar gas and dust. The cloud collapsed, possibly due to the shockwave of a nearby exploding star, called a supernova. When this dust cloud collapsed, it formed a solar nebula—a spinning, swirling disk of material.
At the center, gravity pulled more and more material in. Eventually the pressure in the core was so great that hydrogen atoms began to combine and form helium, releasing a tremendous amount of energy. With that, our Sun was born, and it eventually amassed more than 99 percent of the available matter. Continue reading from NASA
