But seriously—one writer who solved this problem was John Norman in his “Chronicles of Counter-Earth” [which, except for its rabid misogyny, was a great SF series]. The planet Gor was kept perpetually 180 degrees from Earth’s orbit by Gravitational Manipulation. Its Masters had actually moved it here from another Solar System. We have no idea what’s on Earth 2. Maybe its Rulers have mastered gravity just as the Priest-Kings did.