Universe Sandbox

Universe Sandbox => Universe Sandbox | Support & Bugs => Topic started by: tkulogo on February 21, 2019, 06:14:36 AM

Title: Orbital Stability
Post by: tkulogo on February 21, 2019, 06:14:36 AM
I have a moon in my simulation that starts out in a circular 15 hour orbit in the equatorial plane of the planet, both bodies are tidally locked to each other, and the rotational axes are aligned. After a decade or two of simulation, the moon's orbit is inclined and eccentric, and the moon's rotational axis is tilted. I don't know that this is a bug. I suspect I just don't know everything about what makes an orbit stable. Can anyone clue me in? The moon's name is Hammer and is labeled "125 Hammer C4a" in the simulation I've posted in the "share your creations" thread, if that helps.
Title: Re: Orbital Stability
Post by: Cesare on July 15, 2019, 07:25:32 PM
This may be a bug. I am not sure. However, if both objects are orbiting each other, whether or not they are tidally locked, orbits can become somewhat eccentric. The overtime of circular to eccentric orbits could be because of an objects have too little or too much mass.

If you make a new system by placing a random star in a new simulation, then planets orbiting that star, then if the orbits are circular, then they should remain circular even if millions of years passes by. However, if you add a planet with too much mass, then that will could the orbits to become eccentric and lose stability. In the process, planets with too much mass can destabilize other orbits and even cause some planets to be thrown out of the system.

If you find there is a bug with circular orbits on low mass objects, then just report the bug, but remember to be truthful in your bug reports. Developers don't want fake bug reports. Only real ones.