I'm an amateur novelist and trying to build the world of a novel. Its solar system has a different number of planets and the earth a different number of moons. I'd like to add some reality in terms of the gravity balance or the orbital period. So hopefully I can do some calculation using software.
The features I want
- free software
- can change the number, the diameter, the mass and the distance from the sun of the celestial bodies
- can observe the movement of the celestial bodies from "a bird's-eye view" in the space
- can view the sky from the earth surface with planets and moons
I googled with "physical simulator celestial bodies" and it didn't help me so much. I searched this forum with "n-body simulator" and "celestial simulator" to get no results at all.
If some of you know a good app, would you kindly tell me about it?