How should we assess evidence of aliens or intelligent life? MSNBC’s Ari Melber interviews astrophysicist Neil deGrasse Tyson and former CIA director John Brennan about that challenge in the wake of a new Pentagon report. Brennan says the U.S. must “try to understand what is unexplainable,” while ...

Is there other intelligent life in the universe? A new Pentagon report is sparking new intrigue, but it only scratches the surface. In this special report, MSNBC journalist Ari Melber traces the history of UFO sightings; the clash between empiricism and government secrecy; and how the advance of ...