AstroGrav Help /Sample Simulations /Abstract Systems /Binary Asteroid FormationVersion 5.1

Binary Asteroid Formation

This simulation illustrates the first stage of a possible mechanism for the formation of a binary asteroid from a single asteroid. The single asteroid is in the form of a rubble pile, which is rotating fast enough to start shedding material from its equatorial region.

The theory is that a single asteroid slowly rotates faster and faster due to the YORP (Yarkovsky-O'Keefe-Radzievskii-Paddack) effect, and eventually reaches a rotational speed at which material near the equator gently floats off into orbit around the asteroid. Eventually, the material that has floated off gathers together under its mutual gravitational attraction and forms a satellite, so that the original single asteroid is transformed into a binary asteroid. This simulation demonstrates the 'floating off' stage of this process. The satellite formation stage takes far longer, and would probably require the use of many more objects to simulate properly.

You can run the simulation to see how the initial rubble pile gradually loses objects, most of which end up in elliptical orbits, but some of which end up in hyperbolic orbits. Since different computers run at different speeds, you may need to edit the evolution time step to get the simulation to run at an acceptable rate.