US
Researchers are hunting for 'technosignatures' such as communications signals that may originate from alien beings
Protocols are based around scenario in which a pilot on a training or surveillance mission encounters a UFO mid-flight
Astronomers might be able to make out strange variations in the light signatures of distant planets
US military unit apologises for the tweet
From alien invasion to the end of times, people speculate the worst
Luis Elizondo was ex-chief of the $22 million 'Advanced Aerospace Threat Identification Programme'
Most believers in intelligent alien life were in Russia, trailed closely by Mexico and China
The original album is still floating in space and should be in perfect condition
Three chicks were caught on film by residents who believed they had come across extraterrestrials
Kepler mission team released a survey of 219 potential exoplanets detected by the space observatory