Back in the late sixties, the CIA was experimenting on different approaches to space travel. Among these were a program that altered the minds of subjects to make them evolve, giving them the ability to travel in space by way of thought. They would, ideally, sprout wings and take off into the infinite reaches of space, in search for life and resources. Most of the subjects ended up dead during the procedure.
Only one of them did reach the angel-like state without any significant mutations. However, upon her awakening, she destroyed the lab in which she was born, and took off into space with agents on her tail.