Simple orbit speed based off of distance?

[Guest]

Hi I am trying to work out the most simple method of calculating the orbit speed of an object based off it's distance from the the object it's orbiting.
This is for a space scene in a video game I am developing and I know there are ways of calculating this using mass but there is no mass in this scene.
Any ideas would be much appreciated!

[Guest]

Is the speed constant ?
There may be a loss of-orbital energy
Then V is changing (V-decreases)

[Guest]

Is the speed constant ?
There may be a loss of-orbital energy
Then V is changing (V-decreases)

The speed needs to be constant for each object but it's for a solar system so the outer planets need to have a slower velocity than the inner planets.

[Guest]

Problem solved thanks anyway!