Moonlight is borrowed light. Gola 5 of the Āryabhaṭīya (499 CE) states that the Moon, the planets, and the Earth itself are dark spheres: half of each lies in its own shadow, and the half turned toward the Sun is lit. Lunar phases stop being an omen and become geometry. In Greece, Anaxagoras reached the same insight around 450 BCE — and was reportedly prosecuted for impiety. Aryabhata wrote it into a textbook that stayed on the curriculum for a thousand years.