Grimoire Nier is basically a series of novels and an encyclopedia. https://docs.google.com/document/u/0/d/1vEP2iZ52P-DWhQBQ2Is6R8Wjao99AGi0YuWShTvA-tA/mobilebasic#h.05bd454b43f7 The interview with Yoko Taro says that the axis of the Earth has changed. This is also from the World of Recycled Vessel from the Nier game. Seems to imply it happened by the time or after Angelus and the Queen Beast arrived on Earth and when they brought magic to the world. In Nier Automata, 9S explains the cycle of light and dark doesn't exist, the sun doesn't leave the sky anymore. In Nier Automata, one of the Resistance members says that something happened to the moon. https://theark.wiki/w/Yoko_Taro_Q%26A_for_Dengeki_Playstation In this Dengeki Playstation interview Yoko Taro confirming the permanent day and night cycle.