An expert has claimed that aliens don't consider humans intelligent enough to visit Earth.
Earth
Avi Loeb, an astronomer at Harvard University believes that extraterrestrials do not consider humans "attractive" due to their intellect and because they feel that people will not cooperate with them.
He told the Daily Star newspaper: "It's possible that we are not that attractive and we are not very interesting in terms of our intelligence.
"For some reason humans do not cooperate and that's really unfortunate, and it's not a sign of intelligence so I can imagine a much smarter kid on the block."
Loeb also believes that people should set up UFO detection posts wherever sightings are recorded.
He said: "People can report things from personal experience that are not necessarily true.
"We should invest a relatively small sum of money, it will not cost much, in deploying the best instruments we have now in the same sites from where the reports came and monitor the environment for a long enough time."