The 144,000 are not "caught up" to God
These will all be mortals of the children of Israel and the first saved [redeemed] believers of the coming tribulation period
Their mission will be to preach the gospel of the Lord's soon coming millennial kingdom which will be established on the earth just after those days of tribulation [Matthew 24:29-31]
And the Lord will lead them [the world at the time will not see Him doing this]
And they will have to be sealed for their supernatural protection from the wiles of the tribulation
The Lord's judgment will not begin until these are sealed for protection
Read the following verses of scripture very carefully:
7:1 And after these things I saw four angels standing on the four corners of the earth, holding the four winds of the earth, that the wind should not blow on the earth, nor on the sea, nor on any tree.
7:2 And I saw another angel ascending from the east, having the seal of the living God: and he cried with a loud voice to the four angels, to whom it was given to hurt the earth and the sea,
7:3 Saying, Hurt not the earth, neither the sea, nor the trees, till we have sealed the servants of our God in their foreheads.
7:4 And I heard the number of them which were sealed: and there were sealed an hundred and forty and four thousand of all the tribes of the children of Israel.
9:1 And the fifth angel sounded, and I saw a star fall from heaven unto the earth: and to him was given the key of the bottomless pit.
9:2 And he opened the bottomless pit; and there arose a smoke out of the pit, as the smoke of a great furnace; and the sun and the air were darkened by reason of the smoke of the pit.
9:3 And there came out of the smoke locusts upon the earth: and unto them was given power, as the scorpions of the earth have power.
9:4 And it was commanded them that they should not hurt the grass of the earth, neither any green thing, neither any tree; but only those men which have not the seal of God in their foreheads.
14:1 And I looked, and, lo, a Lamb stood on the mount Sion, and with him an hundred forty and four thousand, having his Father's name written in their foreheads.
14:2 And I heard a voice from heaven, as the voice of many waters, and as the voice of a great thunder: and I heard the voice of harpers harping with their harps:
14:3 And they sung as it were a new song before the throne, and before the four beasts, and the elders: and no man could learn that song but the hundred and forty and four thousand [on the earth], which were redeemed [saved] from the earth.
14:4 These are they which were not defiled with women [their ancestors like Solomon were led into idolatry by foreign women]; for they are virgins. These are they which follow the Lamb whithersoever he goeth. These were redeemed from among men, being the firstfruits [the first to be saved in the tribulation period] unto God and to the Lamb.
14:5 And in their mouth was found no guile: for they are without fault before the throne of God.
14:6 And I saw another angel fly in the midst of heaven, having the everlasting gospel to preach unto them that dwell on the earth, and to every nation, and kindred, and tongue, and people, [Matthew 24:14]
14:7 Saying with a loud voice, Fear God, and give glory to him; for the hour of his judgment is come: and worship him that made heaven, and earth, and the sea, and the fountains of waters.