I used to have an excellent online calculator that enabled me to show the possible orbits of a satellite around a larger secondary body (e.g. a moon) which itself was in orbit around (say) a planet. Unfortunately my local PC repair shop unwittingly deleted the calculator during a refurb. And since I can't recall the scientific/technical term for this "three-body" gravitational arrangement, I'm no longer able to locate online the calculator in question. I would therefore be very grateful if anyone can help me here. PS. Unhappily I don't have anything like the mathematical skillset to do these calculations by hand. Thanks in advance. 

 

 

Searching net for "online three body calculator" e.g.

https://www.google.com/search?q=online+three+body+calculator

gives this:

https://www.desmos.com/calculator/icaqw49qeq

where icaqw49qeq is data about initial condition.

 

It's okay. I have it now. . . it's the 'Hill Sphere" set of calculations I was seeking. Phew. . .

https://en.wikipedia.org/wiki/Hill_sphere