Among the Signs of the Might and Power of Allah are the Night and Day, and the Sun and Moon

يُغْشِى الَّيْلَ النَّهَارَ يَطْلُبُهُ حَثِيثًا

(He brings the night as a cover over the day, seeking it rapidly) (7:54). Allah says here:

In verse 38, it was said: وَالشَّمْسُ تَجْرِ‌ي لِمُسْتَقَرٍّ‌ لَّهَا ۚ ذَٰلِكَ تَقْدِيرُ‌ الْعَزِيزِ الْعَلِيمِ (And the sun is quickly proceeding towards its resting place. That is the designing of the All-Mighty, the All-Knowing. 36:38). The word: لِمُسْتَقَر mustaqarr) is used to denote place of rest as well as time of rest, that is, it could be time-oriented and, space-oriented too. Then, this word is also employed in the sense of the end or destination of a course or journey - even if another journey begins immediately after it without any break or stillness (as mentioned by Ibn Kathir).

Some respected commentators have taken the word: لِمُسْتَقَرّ (mustaqarr) at this place as a time-oriented destination, that is, when the sun reaches the end of its movement already determined - and that time is the Day of Doom (the Qiyamah). In the light of this Tafsir, the verse would mean that the sun is moving on its orbit supported by such a precise and perfect system that does never betray the difference of even a minute or second. Thousands of years have passed over this orbit. But, all this is not everlasting. There is a particular point in time and space for it. When that is arrived at, this solar system and the movement will stop, end - and that is the Day of Qiyamah. This Tafsir has been reported from Qatdaha:sv (Ibn Kathir).