private void Start()
 {
     for (int i = 0; i < numCelestialBodies; i++)
     {
         CelestialBody celestialBody =
             Instantiate(celestialBodyPrefab, this.transform).GetComponent <CelestialBody>();
         celestialBody.SetSize(1);
         Rigidbody rb = celestialBody.GetRigidBody();
         rb.useGravity      = false;
         rb.velocity        = startingTranslationalVelocity * (new Vector3(Random.Range(-1f, 1f), Random.Range(-0.5f, 0.5f), Random.Range(-1f, 1f)));
         rb.angularVelocity = startingRotationalVelocity * (new Vector3(Random.Range(-1f, 1f), Random.Range(-1f, 1f), Random.Range(-1f, 1f)));
         celestialBody.transform.position = startingPositionScalar * new Vector3(Random.Range(-1f, 1f), Random.Range(-0.1f, 0.1f), Random.Range(-1f, 1f));
         celestialBody.GetBody().GetComponent <Renderer>().material = material;
     }
 }