Immediately after the tribulation of those days shall the sun be darkened, and the moon shall not give her light, and the stars shall fall from heaven, and the powers of the heavens shall be shaken:
This is the “Coming of the Lord”. You read here that the first (Satan’s) tribulation is ending as Christ arrives for this tribulation. The stars and the moon are not visible because of the brightness that Christ radiates; He produces a light so bright that you cannot see them. You begin to learn about God’s Tribulation in Rev. 6:17 KJV:
For the great day of his wrath is come; and who shall be able to stand?
You shall be able to stand…You can count on it. 2 Peter 3:12 KJV tells about the wrath of God:
Looking for and hasting unto the coming of the day of God, wherein the heavens being on fire shall be dissolved, and the elements shall melt with fervent heat?
God is not angry with you! Hebrews 12:29 KJV tells you about this fire:
For our God is a consuming fire.
Others do feel the effects of this tribulation; the very moment Christ returns, His Consuming Fire does away with the elements, including the fallen angels. But just like the Hebrew children, Meshack, Shadrack, and Abed-nego were protected; you will be too. Not a hair on your head will be singed.
These verses describe the Second Tribulation; it is over about as soon as it begins. It takes very little time for God to rid the earth of the elements.
Satan’s Tribulation precedes this one and, with God’s permission, he is coming to convince you that he is Jesus Christ. Rev. 6:15-16 KJV gives some insight as to how effective he is going to be:
 And the kings of the earth, and the great men, and the rich men, and the chief captains, and the mighty men, and every bondman, and every free man, hid themselves in the dens and in the rocks of the mountains
 And said to the mountains and rocks, Fall on us, and hide us from the face of him that sitteth on the throne, and from the wrath of the Lamb:
The arrival of Christ ends Satan’s Tribulation as it brings reality back into the world. Seeing Christ, they realize that they had accepted Satan in his place. They are so embarrassed that they hide themselves and pray for the mountains to fall on them. You know, if the imposter had led you into believing that he was Jesus Christ, you may just do the same.