Job 25-27

Bildad's proclamation in verse 7 that God hung the earth in emptiness makes complete sense to modern people. But I wonder how the people before telescopes and rocket ships understood this thought? They knew that the sky was immense and no matter how hard they tried they could not touch Its limits. But the sky was not empty. Even the least educate could witness the stars that filled the night sky. These looked no further away than the birds that replaced them during the day. The sun and moon which followed the same mysterious path never collided. I wonder what  those ancient believers might have understand this emptiness to be?
Stuart