Firmament

In Biblical cosmology, the firmament is the structure above the atmosphere, conceived as a vast solid dome. According to the Genesis creation narrative, God created the firmament to separate the "waters above" the earth from the "waters below" the earth. The word is anglicized from Latin firmamentum, which appears in the Vulgate, a late fourth-century Latin translation of the Bible.

The firmament is described in Genesis 1:6–8 in the Genesis creation narrative:

Then God said, “Let there be a firmament in the midst of the waters, and let it divide the waters from the waters.” Thus 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. So the evening and the morning were the second day.

The word "firmament" is first recorded in a Middle English narrative based on scripture dated 1250. It later appeared in the King James Bible. The word is anglicised from Latin firmamentum, used in the Vulgate (4th century). This in turn is derived from the Latin root firmus, a cognate with "firm". The word is a Latinization of the Greek , which appears in the Septuagint (c. 200 BC).

The word "firmament" is used to translate raqia, or raqiya‘ ( רקיע), a word used in Biblical Hebrew. It is derived from the root raqa‘ ( רקע), meaning "to beat or spread out", e.g., the process of making a dish by hammering thin a lump of metal.

Like most ancient peoples, the Hebrews believed the sky was a solid dome with the Sun, Moon and stars embedded in it. According to The Jewish Encyclopedia:

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