Since Muslims in the West claim that science confirms the Qur'an, we should work diligently to explain to them what the Qur'an says, and how Muhammad obviously interpreted it. The following two quotations, when used together, are devastating and unanswerable:
Qur’an 18:83-86—And they ask you about Dhul-Qarnain. Say: “I shall recite to you something of his story.” Verily, We established him in the earth, and We gave him the means of everything. So he followed a way. Until, when he reached the setting place of the sun, he found it setting in a spring of black muddy (or hot) water. And he found near it a people.
Sunan Abu Dawud 3991—Abu Dharr said: I was sitting behind the Apostle of Allah who was riding a donkey while the sun was setting. He asked: Do you know where this sets? I replied: Allah and his Apostle know best. He said: It sets in a spring of warm water.
For more on Muhammad, the Qur'an, and the setting of the sun, here are some articles:
Sam Shamoun, "Muhammad and the Sun's Setting Place"
Cornelius, "The Sun in the Muddy Pool and the Prophethood of Muhammad"
Sam Shamoun and Jochen Katz, "Islam and the Setting of the Sun"
Martin Taverille, "Dhu’l Qarnayn and the Sun Controversy in the Qur’an: New Evidence"
In case you missed the first entry in this series: