Harvard professor and theoretical physicist Avi Loeb claims that an alien species visited earth in 2017.

Aliens, Harvard
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For his upcoming book, Extraterrestrial: The First Sign of Intelligent Life Beyond Earth, Loeb explains his belief that the "Oumuamua," a viral interstellar object which was first discovered on October 19th, 2017, was not simply a rock, but instead an alien object.

"What would happen if a caveman saw a cellphone?" Loeb rhetorically asked the New York Post in a recent interview. "He’s seen rocks all his life, and he would have thought it was just a shiny rock."

Loeb cites the object's dimensions and it's movement as the primary reasons he doesn't believe Oumuamua is natural. 

"The excess push away from the sun, that was the thing that broke the camel’s back," he said.

"If we are not alone, are we the smartest kids on the block?" Loeb asked. "If there was a species that eliminated itself through war or changing the climate, we can get our act together and behave better. Instead, we are wasting a lot of resources on Earth fighting each other and other negative things that are a big waste."

Extraterrestrial: The First Sign of Intelligent Life Beyond Earth is expected to release on January 26, 2021.