AstroGrav Help /Sample Simulations /Solar System /Comets /2P (Encke)Version 5.1

2P (Encke)

This simulation illustrates the long-term fate of Comet 2P/Encke, which is highlighted in the table to make it easier to watch the changing orbital elements. As time passes, the gravitational influence of the planets causes the comet's eccentricity to get larger and larger. As a consequence, its perihelion distance becomes smaller and smaller, until it eventually becomes less than the Sun's radius and it collides with the Sun.

In this simulation, the collision with the Sun happens around AD 80,000, and it may take over an hour to evolve that far. However, the orbit of Encke's comet is highly chaotic, and tiny changes in the initial state of the system can shift the time of the collision by thousands of years. Because of this, it is not possible to predict the time of the collision with any accuracy.

The names of the brighter background stars are shown, and their motion is clearly visible over this long period of time. This is best observed by stopping and re-starting evolution every few minutes, and then using a sequence of undos and redos to quickly move backward and forward over large periods of time.

The evolution time step is set to one year, which is why the Earth appears to be fixed in position while the simulation runs. 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.