Density of our Asteroid Belt is lower than we think

In our Asteroid Belt, which is between Mars and Jupiter, the density is very low, contrary to what everyone thinks because of movies. Proof of this are the Pioneer 10 / 11 that were launched in the early '70s and also the Voyager 1 / 2 that crossed the Asteroid Belt. Every asteroid that crossed them did so from over a million kilometres away.

Actually there are asteroids anywhere in the Solar System, in fact near the Earth we have several thousand considered as dangerous objects, they're catalogued and are about 4000. They're called Near-Earth Objects (NEOs) precisely because of their proximity to Earth.

In this belt is where there is the highest concentration of asteroids within the Solar System, about 90% are there and is an area ranging from 2.06 to 3.27 astronomical units (an astronomical unit is the distance between Earth and Sun).

Translating this data into kilometres, it would cover an area ranging from 308 million kilometres to 489 million kilometres. If we compared the Solar System to a table, with the Sun in the center and the planets spinning, there would be all these asteroids on the table, spinning around. There would be very few who were outside that plane that would form the table. This plane is what we know as the ecliptic plane.

Mass contained in this volume is 3 trillion tons, no more than half of which is made up of four of these asteroids: Vesta, Palas, Ceres, Hygiea. Ceres is not even considered an asteroid because it's almost a dwarf planet, like Pluto.

From these data we could deduce the density, in fact there's one asteroid every two million kilometres, in other words there are 250 billion asteroids with a diameter of more than one metre and the distance between asteroids with a diameter of more than one metre is 92,000 km.