void Start()
{
AsteroidManager am = new AsteroidManager();
AsteroidData[] asteroidDatas = am.ReadAsteroids();
// Instantiate all asteroids from asteroidDatas.
foreach (AsteroidData ad in asteroidDatas)
{
GameObject newAsteroid = GameObject.CreatePrimitive(PrimitiveType.Sphere);
newAsteroid.transform.position = ad.position;
newAsteroid.transform.localScale = ad.scale;
}
}