Spreadeth, Stretcheth, Stretched
And God said, Let there be a firmament in the midst of the waters, and let it divide the waters from the waters. And God made the firmament, and divided the waters which were under the firmament from the waters which were above the firmament: and it was so. And God called the firmament Heaven. And the evening and the morning were the second day.
( Genesis 1:6-8 ) KJV
We think of earth as down and heaven as up. Heaven above and hell below. Whatever happened on the 2nd day has to allow for the eventual formation of heaven and hell. These are not spiritual concepts.