you might be right, but dont forget that the disk (the earth) is bigger then the spotlight (the sun) ... the rays of the sun can't reach all the continents, the sun reflects its rays on the moon which sometimes appears to be illuminated from below, but sometimes illuminated laterally, this must prove that the sun, in such circonstance, would be shining in front of it, so imagine that the earth is a plate, and the sun a small point illuminating its semi-circle ! I hope this will help you to answer your question and personally I agree with it " the divider of the daybreak and has made the night for rest and the sun and moon for calculation. That is the determination of the Exalted in Might, the Knowing (GOD) " 6:96 the Holy Quran