public static void Update()
        {
            foreach (BaseObject obj in _objs)
            {
                obj.Update();
            }
            foreach (Bullet b in _bullets)
            {
                b.Update();
            }
            for (var i = 0; i < _asteroids.Count; i++)
            {
                if (_asteroids[i] == null)
                {
                    continue;
                }
                _asteroids[i].Update();
                for (int j = 0; j < _bullets.Count; j++)
                {
                    if (_asteroids[i] != null && _bullets[j].Collision(_asteroids[i]))
                    {
                        System.Media.SystemSounds.Hand.Play();
                        _asteroids[i] = null;
                        _bullets.RemoveAt(j);
                        j--;
                    }
                }
                if (_asteroids[i] == null || !_ship.Collision(_asteroids[i]))
                {
                    continue;
                }
                _ship.HPLow(Rnd.Next(1, 10));
                System.Media.SystemSounds.Asterisk.Play();
                if (_ship.HP <= 0)
                {
                    _ship.Die();
                }
            }

            foreach (MedicalKit a in medkit)
            {
                a.Update();
            }

            /*for (var i = 0; i < medkit.Count; i++)
             * {
             *  medkit[i].Update();
             *  if (medkit[i] == null) continue;
             *  medkit[i].Update();
             *  for (int j = 0; j < medkit.Count; j++)
             *      if (medkit[i] != null && _ship.Collision(medkit[i]))
             *      {
             *          System.Media.SystemSounds.Question.Play();
             *          medkit[i] = null;
             *      }
             *  if (medkit[i] == null || !_ship.Collision(medkit[i])) continue;
             *  _ship.HPRise(Rnd.Next(1, 20));
             * System.Media.SystemSounds.Asterisk.Play();
             * }*/
        }