Hi guys,
I’m trying to orbit ships around a planet while keeping them facing at 90 degrees. I have this working for the most part but find as the number of ships increases, I’m losing FPS due to the rotation method.

Each ship is moving forward a constant velocity. The rotation method I’m currently using is:
public void Rotate90degs()
{
Vector3 diff = planet.transform.position - transform.position;
float rot_z = (Mathf.Atan2(diff.y, diff.x) * Mathf.Rad2Deg) /* -90 */;
Quaternion newRot = Quaternion.Euler(new Vector3(0,0,rot_z));
transform.rotation = Quaternion.RotateTowards(transform.rotation, newRot, Time.deltaTime * 75f);
}
I know I can make them childs of a rotating game object, but that’s not really going to suit my purposes for this.
Any other suggestions on a more efficient way to do this?