review of planet formation  next topic: small planets

PPM results: Movies

Visualization of 2-D numerical disk-planet interactions

Most movies are made with a corotating camera, i.e. independently of its actual angular speed, the planet lies on the positive x-axis of the picture. This allows for a clearer representation of wave shape changes and planet migration. [To obtain the view in a fixed frame, rotate your screen (or yourself) a couple of turns per second.]

You will sometimes notice a mild shaking of the whole picture. This is not an artifact,
but results from a small and freely evolving eccentricity of the planet in the simulation.
The center of mass of the system is fixed at the origin of coordinates. If the system is
eccentric then both the planet and the disk will oscillate with the orbital period.
Typically, a planet might be started with e=0.01, and by the end of the simulation e would
decay to one-half of that value.

The following movies are fairly similar, and both  simulate a 1 or 1.5-Jupiter mass planet
in a solar nebula somewhat more massive than the minimum-mass solar nebula. Disks are non-selfgravitating in these calculations.

The mass of the planet is introduced over the initial 5-10 periods, to avoid transient disk
response (which PPM would love to keep around, being a low-dissipation numerical
scheme). Our code  (at the particular resolution used, see below) has effective disk
viscosity corresponding to alpha of order few*0.001.

The simulations presented here were done on a 200x200 or 400x400 square grid, covering 4*a(0)
(4 initial semi-major axes of the planet along each direction). The simulated time is
100-150 initial periods. For instance, if the initial distance a(0)=5 AU, the total simulation
time would be up to ~1600 yrs, yet under this short period of time the large simulated mass
of the nebula forced a vigorous migration from a(0)   to a third of that value.

Please click on the selected image to load the .avi simulation.
[xanim is one shareware program that can be used for viewing the movies under Unix.
PCs should have no trouble with .avi, but if your browser displays a static first frame,
please make sure to click on it to start the video.]


      7.2 MB .AVI
Gap opening, migration type II (in a gap) , 200x200 grid; final mass of the planet = 1 Jupiter mass; disk mass 0.02 M_sun

      12.7 MB .AVI
Gap opening, migration type II (in a gap) , 200x200 grid, final mass of the planet = 1.5 Jupiter masses; disk mass = 0.02 M_sun.
At the end of simulation the disk is artificially faded out (to illustrate the fact that  protoplanetary disks are disappearing after ~1-10 Myr) so that only the star and the planet on a tight orbit remain.

      8.2 MB .AVI   (RECOMMENDED!)
Gap opening, migration type II (in a gap) , 400x400 grid;  planet grows from 10 Earth to 1.5 Jupiter mass; disk mass 0.03 M_sun.