What do we know about the rainbow's existence prior to the Great Flood?

In Genesis 9:11-17 God says that He established the rainbow as the sign that He will never again judge the earth by another Great Flood (which took place about 2348BC). Does this mean that before this date the rainbow never existed? Is there any proof that the rainbow existed prior to the Great Flood? 

Genesis 9:11 - 17

ESV - ¹¹ I establish my covenant with you, that never again shall all flesh be cut off by the waters of the flood, and never again shall there be a flood to destroy the earth. ¹² And God said, "This is the sign of the covenant that I make between me and you and every living creature that is with you, for all future generations:

Clarify • Share • Report • Asked July 10 2020 • Jeffrey Smith Supporter