It is He Who made the sun to be a shining glory and the moon to be a light (of beauty), and measured out stages for her; that ye might know the number of years and the count (of time). Nowise did Allah create this but in truth and righteousness. (Thus) doth He explain His Signs in detail, for those who understand.
( سورة يونس , Yunus, Chapter #10, Verse #5)
We have made the Night and the Day as two (of Our) Signs: the Sign of the Night have We obscured, while the Sign of the Day We have made to enlighten you; that ye may seek bounty from your Lord, and that ye may know the number and count of the years: all things have We explained in detail.
( سورة الإسراء , Al-Isra, Chapter #17, Verse #12)
He will say: "What number of years did ye stay on earth?" They will say: "We stayed a day or part of a day: but ask those who keep account."
( سورة المؤمنون , Al-Mumenoon, Chapter #23, Verse #112=113)