Aliens maintain wiping themselves out earlier than people uncover them.
NASA scientists suppose that extraterrestrials might have existed all through the historical past of the universe however have by no means survived lengthy sufficient to make contact with Earth.
Boffins counsel that a number of the aliens can have been worn out by uncontrollable occasions comparable to an asteroid hitting a planet however others might have been self-inflicted by elements comparable to local weather change.
The research says: “Proof of life ought to exist in abundance on our galaxy alone.
“And but in follow we have produced no clear affirmation of something past our personal planet.
“So, the place is everyone?
“The silence of the universe past Earth reveals a sample of each human limitation and steadfast curiosity.”
The NASA specialists issued a warning that “existential catastrophe might lay in wait” as society advances in the direction of house exploration and ramps up the hunt for alien life.