see also sunrise and sunset for some interesting facts.
The literal meaning of orbit is "swim", and does not indicate a path as known in science. The Greeks, Egyptians and Druids knew about the orbits of the moon and the sun long before Muhammad. Also, the orbits are not comparative, since the moon orbits the earth that orbits the sun. The sun orbits the galactic center at about 144 miles per second, while the moon orbits the earth at approximately 2,300 miles per second. In truth, the moon is affected by the gravitation pull of both the earth and the sun, and it cannot escape its pull due to its mass. No galactic body floats on its own, but is affected by all gravitational forces.
What is that supposed to mean? "the solar solar system is indeed evolving toward a point situated in the constellation of Hercules whose exact location is firmly established." (Maurice Bucaille, The Bible, the Quran and Science). But that is not true since the universe is constantly expanding and changing, and no place is exactly fixed.
Muslims have said that this passage refers to Alexander the Great. In al-Kahf 18:86, he is said to reach the setting-place of the sun, whatever that means, and there found water and a people. Where is that place that the sun sets? al-Kahf 18:86 clearly has the perspective for a man on earth observing the skies, and sees the sun orbiting the earth.