Yunus · 10:5

5. It is He Who made the sun radiate light and made the moon a light illuminated by it, determining its progression through twenty-eight phases – a phase being the change it goes through every twenty-four hours – so that people would know the number of days by the sun and the number of months and years by the moon. Allah did not create the heavens and the earth and what is in them except with the truth, revealing His power and might to people. Allah makes clear these obvious signs and evidence that there is no god but Him for a people who know how to draw conclusions from such facts.