The New Earth will not be illuminated by the Sun. https://www.bible.com/bible/59/REV.21.ESV

Revelation 21:5 And he that sat upon the throne said, Behold, I make all things new. And he said unto me, Write: for these words are true and faithful.

God and Jesus Christ sit upon the throne in each individual Christian soul. The throne is symbol of the Holy Spirit recieved, active and alive in each in each Christian soul. The Revelation 21 new heaven and new earth is the spiritual kingdom in Christ born of the Holy Spirit in each individual Christian soul.

Revelation 21:9 And there came unto me one of the seven angels which had the seven vials full of the seven last plagues, and talked with me, saying, Come hither, I will shew thee the bride, the Lamb's wife.

The Lamb’s wife in the spiritual interpretation of the book of Revelation is the individual Christian soul in union with Jesus Christ. The marriage of the Lamb is with each individual Christian soul, united to Jesus Christ.

Revelation 21:10 And he carried me away in the spirit to a great and high mountain, and shewed me that great city, the holy Jerusalem, descending out of heaven from God,

New Jerusalem is the individual Christian soul married to the Lamb. God sees each soul in union with Jesus Christ all at the same time. This is the great multitude of Revelation chapter 19.

Revelation 19:1 And after these things I heard a great voice of much people in heaven, saying, Alleluia; Salvation, and glory, and honour, and power, unto the Lord our God:

2 For true and righteous are his judgments: for he hath judged the great whore, which did corrupt the earth with her fornication, and hath avenged the blood of his servants at her hand.

3 And again they said, Alleluia And her smoke rose up for ever and ever.

4 And the four and twenty elders and the four beasts fell down and worshipped God that sat on the throne, saying, Amen; Alleluia.

5 And a voice came out of the throne, saying, Praise our God, all ye his servants, and ye that fear him, both small and great.

6 And I heard as it were the voice of a great multitude, and as the voice of many waters, and as the voice of mighty thunderings, saying, Alleluia: for the Lord God omnipotent reigneth.

7 Let us be glad and rejoice, and give honour to him: for the marriage of the Lamb is come, and his wife hath made herself ready.

The marriage of the Lamb comes to each individual Christian soul through the Holy Spirit creating the kingdom in each soul that puts faith in the life, kingdom, and reign of Jesus Christ.

Revelation 21:22 And I saw no temple therein: for the Lord God Almighty and the Lamb are the temple of it. 23 And the city had no need of the sun, neither of the moon, to shine in it: for the glory of God did lighten it, and the Lamb is the light thereof.

The New Creation in each individual Christian soul is new Jerusalem and the marriage of the Lamb, active and alive by the Holy Spirit building the Kingdom of Christ in each soul that recieves the the Revelation of Jesus Christ.

May the Holy Spirit make these words come alive to all who read:

Revelation 22:17 And the Spirit and the bride say, Come. And let him that heareth say, Come. And let him that is athirst come. And whosoever will, let him take the water of life freely.

18 For I testify unto every man that heareth the words of the prophecy of this book, If any man shall add unto these things, God shall add unto him the plagues that are written in this book:

19 And if any man shall take away from the words of the book of this prophecy, God shall take away his part out of the book of life, and out of the holy city, and from the things which are written in this book.

20 He which testifieth these things saith, Surely I come quickly. Amen. Even so, come, Lord Jesus.

21 The grace of our Lord Jesus Christ be with you all. Amen.