Praise be to Allah.
The sun is one of the signs of Allaah, for which He has created a course in which it runs, and a system from which it does not change. It rises in the east every day, but when Allaah gives permission for the world to end and the Hour to begin, He will command it to rise from the west. At that time all people will believe and will be certain of the resurrection, but their faith will not avail them anything at that moment, except for those who believed before.
Allaah says (interpretation of the meaning):
“The day that some of the Signs of your Lord do come, no good will it do to a person to believe then, if he believed not before, nor earned good (by performing deeds of righteousness) through his Faith”
al-Bukhaari (4635) and Muslim (157) narrated that Abu Hurayrah (may Allaah be pleased with him) said: The Messenger of Allaah (peace and blessings of Allaah be upon him) said: “The Hour will not begin until the sun rises from its place of setting. When it rises from its place of setting, all people will believe, but on that day ‘no good will it do to a person to believe then, if he believed not before,’ [al-An’aam 6:158].”
Allaah says, describing the movement of the sun and its submission to the command of Allaah (interpretation of the meaning):
“And the sun runs on its fixed course for a term (appointed). That is the Decree of the All‑Mighty, the All‑Knowing”
This is explained in the Sunnah. Al-Bukhaari (3199) narrated that the Prophet (peace and blessings of Allaah be upon him) said to Abu Dharr, when the sun set: “Do you know where it goes?” He said: Allaah and His Messenger know best. He said: “It goes and prostrates beneath the Throne, and it asks for permission, and permission is given to it. But soon it will prostrate and it will not be accepted from it, and it will ask for permission and permission will not be given to it, and it will be said to it: ‘Go back from where you came.’ So it will rise from its place of setting, and that is what Allaah says (interpretation of the meaning): “And the sun runs on its fixed course for a term (appointed). That is the Decree of the All‑Mighty, the All‑Knowing.’”
Al-Tahhaawi (may Allaah have mercy on him) said in his well known book al-‘Aqeedah: We believe in the portents of the Hour, the emergence of the Dajjaal, the descent of ‘Eesa ibn Maryam (peace be upon him) from heaven, and we believe that the sun will rise from the west. End quote.
Shaykh Ibn ‘Uthaymeen (may Allaah have mercy on him) said: Similarly, the sun and moon travel in their orbits along the courses decreed for them until an appointed time, until Allaah will give permission for this universe to be destroyed. Then the sun will emerge from its place of setting as is narrated in Saheeh al-Bukhaari from Abu Dharr. Then he quoted the hadeeth mentioned above.
This hadeeth clearly indicates that the sun travels by itself, as is also indicated by the verses in which Allaah says (interpretation of the meaning):
“And the sun runs on its fixed course”
“Each running (on a fixed course) for an appointed term”
“each in an orbit floating”
This evidence proves false the idea that the sun is fixed and does not move, and indicates that this is a false notion which should be refuted. End quote from Majmoo’ Fataawa wa Rasaa’il al-Shaykh Ibn ‘Uthaymeen (6/195).
Conclusion: one of the signs of the onset of the Hour is that the sun will rise from the west instead of rising from the east. When that happens, it will indicate that the onset of the Hour is very close, and at that time belief will not benefit the kaafir at all.
And Allaah knows best.