eli5 Does gravity act the same for large objects as it does for small objects. So if I were to shrink planet Earth and the moon to say half the size and the distance between them too then would they continue orbiting. Would this also apply if they somehow became much larger?

Question

eli5 Does gravity act the same for large objects as it does for small objects. So if I were to shrink planet Earth and the moon to say half the size and the distance between them too then would they continue orbiting. Would this also apply if they somehow became much larger?

In: 9

Answer 1

Yes to your first question, “not quite” to the second. Laws of gravity are the same for big and small object. However, these laws state that the force between objects is proportional to their mass and inversely proportional to their distance squared (distance * distance).

So, they can still orbit each other (any pair of objects in space can orbit each other if their relative speed allows it) but just dividing all sizes in half (unless you mean just compressing the Earth and the Moon while keeping the mass and distance intact) will screw up the equations, so their orbital speeds and parameters of the orbit will be different.