In Revelation, Heaven is the place or world that is acknowledged by the true people of God:
Rev. 5:13 Then I heard every creature in heaven and on earth and under the earth and in the sea, and all that is in them, singing,
?To the one seated on the throne and to the Lamb
be blessing and honor and glory and might
forever and ever!?
The Lamb is on the Throne in heaven and earthlings are to acknowledge that Throne.
Rev. 18:1 After this I saw another angel coming down from heaven, having great authority; and the earth was made bright with his splendor.
These two reference then trade in two ideas: God is in Heaven and God’s Throne is in Heaven, and earthlings are to acknowledge the creator of heaven and earth.