Asteroids are celestial bodies that orbit the Sun and are too small to be considered planets. They are concentrated between Mars and Jupiter.
Asteroids are metallic – forming celestial bodies that orbit the Sun. They are not classified as planets because they are not large enough to do so. Most asteroids are concentrated between the orbits of Mars and Jupiter , a region called the asteroid belt.
How were asteroids formed?
Everything we know about these celestial bodies comes from the analyzes done on those that fell to Earth. The chemical elements that commonly form asteroids are silicate, iron , and nickel .
Asteroids can be the remains of a planet that has been destroyed or simply materials that, since the formation of the Solar System , have never merged to form a planet. This second hypothesis is the most accepted for the explanation of the origin of these celestial bodies.
Bennu is an asteroid about 0.5 km in diameter that travels at a speed of 101,389 km/h. It has been known to astronomers since 1999. There is a 0.04% chance that this asteroid will collide with Earth in the year 2135.
NASA , the US space agency, launched in 2016 the Osiris-REx probe, which will travel to the asteroid Bennu, reaching its surface in 2018. The objective of this space mission is for the probe to return to Earth in 2023 bringing samples of the asteroid. These samples may contain important information about the formation of the Solar System .
If all known asteroids were merged into a single body, the result would be an object with a diameter of approximately 1500 km, less than half the diameter of the Moon.