Following some early work by Stuart Robbins at the University of Colorado at Boulder, I began doing some simulations with the intention of forming moonlets. I began with initial conditions similar to those used by Stuart, but it appears those only form moonlets rarely so I changed some parameters to make a simulation that would form a moonlet more quickly. The movies below show what happens in some of these simulations.
These first two simulations use a uniform particle size fo 1m in radius. The particles have an internal density of 0.9 g/cm^3 and enough are created to produce a geometric optical depth of 0.42 This gives a surface density on the order of 53 g/cm^2.
The movies on this page were made with mencoder (comes with mplayer) and encoded using the Xvid/Divx codec. Viewing them may require a Divx download. Works with Divx player, Windows Media, MPlayer, and others.
Original small simulation (N=225937):
Animated gifs of different orbits. Size ranges from 15 to 93 MB. The last one is probably the best (and the biggest). These show a 2-D image of the whole cell along with a 3-D rendering of a large section of the cell.
Orbits 8-11, Orbits 12-15, Orbits 16-19, Orbits 14-19
This is a Divx encoded movie of the full 22 orbits in the simulation with a zoom in on one particle that spends a lot of time in the moonlet. Notice that when the original moonlet breaks up the particle that is followed is temporarily free again.
Xvid/Divx movie (71 MB)
Large cell simulation (N=677810):
A full movie of the first 29 orbits of the simulation. The top plot shows the whole simulation region. The bottom plot is centered on a particle that is one of the earlier ones in the moonlet. In the bottom frame, the black circles are drawn to size and a single red dot is drawn at the location of the center of all particles. The red dots allow you to better see how many particles are in a group and how they are arranged. If you have a hard time viewing any of these you can download MPlayer and they will all work with it.
Xvid/Divx (400 MB)
Other Stuff :
These are some random gif animations of simulations where I was playing with lighting and 3-D rendering. Some include a size distribution.
No Movement (13 MB)
No Movement with Size Distribution (22 MB)
Moving Light Source: Lit Side (15 MB)
Moving Light Source: Dark Side (9 MB)
