Revelation 21:9-16

9 Then one of the seven angels who had the seven bowls filled with the seven final plagues (afflictions, calamities) came and spoke to me. He said, Come with me! I will show you the bride, the Lamb's wife.

10 Then in the Spirit He conveyed me away to a vast and lofty mountain and exhibited to me the holy (hallowed, consecrated) city of Jerusalem descending out of heaven from God,

The city New Jerusalem is not Jesus’ Bride, we are. John can see us because this is where we will be, in the New Jerusalem, Ephesians 5:31-32.

11 Clothed in God's glory [in all its splendor and radiance]. The luster of it resembled a rare and most precious jewel, like jasper, shining clear as crystal.

12 It had a massive and high wall with twelve [large] gates, and at the gates [there were stationed] twelve angels, and [on the gates] the names of the twelve tribes of the sons of Israel were written:

13On the east side three gates, on the north side three gates, on the south side three gates, and on the west side three gates.

14 And the wall of the city had twelve foundation [stones], and on them the twelve names of the twelve apostles of the Lamb.

15 And he who spoke to me had a golden measuring reed (rod) to measure the city and its gates and its wall.

16 The city lies in a square, its length being the same as its width. And he measured the city with his reed--12,000 stadia (about 1,500 miles); its length and width and height are the same.

We are shown that the walls of the city are 1,500 miles high. That means that there is no lack of atmosphere for us! Everything has become new, even the limitations of outer space has been changed.  

Think of why our Father has made so many planets and universes? Then ask yourself why are we told that the walls of the New Jerusalem are 1,500 miles high? I believe that it is because that all of the guests that we are told are able to attend the Wedding Feast, or spend eternity with us, will continue to have children. People say that there is no marriage in eternity, but when Jesus told us that in Matthew 22, He only said there was no marriage for those who are raised up from the dead. Jesus never said that there would be no marriage for those who are living when our Father returns. We are told repeatedly that the nations come in to the New Jerusalem, Micah 4:2, Revelation 15:4, and Revelation 21:26. So there is going to be a ton of people left and they will continue to have children. There will be no more death, so this earth is just not big enough to sustain all of them. That makes eternity so exciting for me because I think that it would get pretty boring if there were only a few of us there and nothing ever changed. But I honestly believe that there will be new life all of the time and new experiences.