2D Collision without velocity change

Hello,

I have a planet moving around another planet in an ellipse (using gravity). There are constantly collisions between the moving planet and other little objects in space which slow down the planet movement.
Now I want the planet to keep its velocity.
I found solutions like saving the velocity in FixedUpdate and applying it in OnCollisionEnter. But since it is many collisions alle the time it doesn't really work.

Any ideas?

Thank you!

 

Have you tried adjusting the masses? Make the planet significantly heavier than the debris particles and these collisions should have a much lower impact on the planet velocity while also preserving scattering behaviour of the debris particles.

 

Changing the masses would affect the movement. And I need no impact at all because also low impact would affect the velocity and eventually the planet would go down on the mother planet.

 

If anybody else runs into this problem: The solution was to create a child gameobject and add a kinematic Rigidbody and a CircleCollider to it.