Complex sentence: The formula suggests that, extending outward, each planet would be approximately twice as far from the Suny correctly anticipated the orbits of Ceres (in the asteroid belt) and Uranus, but failed as a predictor of Neptune's orbit and has since been discredited further.
Split into simpler sentences: The formula suggests that, extending outward, each planet would be approximately twice as far from the Sun as the one before. The hypothesis correctly anticipated the orbits of Ceres (in the asteroid belt) and Uranus, but failed as a predictor of Neptune's orbit and has since been discredited further.