UFOs worth investigating despite lack of 'real evidence,' former astronaut Scott Kelly says
Four-time astronaut Scott Kelly spoke with Space.com about UFOs and why air and space are so 'prone to optical illusions' that lead to reports of unidentified anomalous phenomena.
![UFOs worth investigating despite lack of 'real evidence,' former astronaut Scott Kelly says](https://cdn.mos.cms.futurecdn.net/h7LU4ZQwztcqaSc2f7MDbC.jpg?#)