As were “the pillar of smoke by day and pillar of fire by night”, it could *also* have been an entirely supernatural object put there intentionally by God.
“pillar of smoke by day and fire by night”
As I have posted elsewhere, my hypothesis (based on a lot of volcano research I have been doing for a book in progress) is that this was a volcanic event east of Egypt, possibly the path across the sea could have been caused by a volcanic process called “inflation”, whereby magma builds up under ground, elevating the ground, until it is erupted somewhere, upon which the ground subsides again. I have seen pictures of a recent eruption in Japan near Usu (sp?) where the ground inflated almost 300 feet.