There are a lot of space rocks up there. More than 100,000 in our solar system alone, according to the Sloan Digital Sky Survey — an incredibly ambitious project to map everything in the sky. Everything.

It’s been running since 2000, and so far has managed to cover about a third of the sky, logging observations about about 500 million objects. That catalogue includes 57,000 stars in the Milky Way, 670,000 galaxies and quasars in the distant universe, and about 100,000 asteroids in the solar system.

Alex Harrison Parker, a postdoctoral researcher at the University of California, was sifting through that data when he noticed that it was possible to separate out the asteroids into different families defined by how they clustered together around larger objects. He dug into it a little further and successfully identified thirty-seven different families with more than 100 members, including twelve with more than 1,000 members.

What’s more, he found that it was possible to separate four of these families out by optical colour alone. So he put together an animation of 100,000 of the asteroids we know of, showing what family they belong to and approximately how big they are. Here it is:

In the video (which you should really watch full-screen if at all possible) you can see every asteroid’s orbital motions playing out, with a timestep of about three days. The average orbital distances of Mercury, Venus, Earth, Mars, and Jupiter are illustrated with rings, but the Sun — which would normally lie in the centre — is not included.

The densest section is the asteroid belt, showing how different families are distributed within. The inner belt conisists mainly of green Vesta-family asteroids, transitioning to blue C-class asteroids in the outer belt and deep red Trojan rocks (those that share an orbit with a planet) beyond.

The trojans are split into two camps, which orbit ahead of and behind Jupiter in its lagrangian points — gravitationally stable zones in an object’s orbit. One side are known as the Trojan camp and the other side are known as the Greek camp. A third camp of asteroids that share a 3:2 orbital resonance with Jupiter are known as the Hildas.

Other named families include the Hungaria family, the Phocaea family, the Cybele group, the Karin cluster, the Veritas cluster, the Datura cluster, and the Iannini cluster.

You can find the full details of Parker’s work, published in Icarus, right here.