aliens

Luis Elizondo used to run a Pentagon office that investigated unidentified flying objects seen by the U.S. military. He says his staff often could not explain what it saw.

The discovery provides our first "glimmer of understanding" about the unexplained, strong waves. Scientists don't think they're from aliens, but they're puzzled by what could be causing them.

Searching for alien life is harder than you might think, because whatever is out there might be really odd. So leading astrobiologists are meeting to advise NASA on how to go about looking for it.