private void SetOrbitCraters(OrbitTypeEnum orbitType)
        {
            switch (orbitType)
            {
            case OrbitTypeEnum.ORBIT1:
                _noOfCraters = 20;
                _distance    = 18;
                break;

            case OrbitTypeEnum.ORBIT2:
                _noOfCraters = 10;
                _distance    = 20;
                break;

            default:
                throw new InvalidOperationException("Invalit Orbit Type");
            }
        }
 public Orbit(OrbitTypeEnum orbitType, double speed)
 {
     _orbitTypeEnum = orbitType;
     _speed         = speed;
     SetOrbitCraters(orbitType);
 }