A strange interstellar object that shot past the Earth in the autumn of 2017 may have been a buoy left floating in space by an alien civilisation, a Harvard professor argues in a new book. Avi Loeb, a theoretical physicist who was chairman of the university’s astronomy department, co-authored a paper in 2018 suggesting that the long, thin object known as ‘Oumuamua may have been a probe sent towards Earth. He has now written a book, Extraterrestrial, in which he suggests that it could have been a thin, disc-shaped sail, powered by starlight, that was once part of a vast communications network. “If we are expecting the bang of gravity-defying ships on the horizon, do we risk missing the subtle sound of other

Source: The Times January 05, 2021 00:00 UTC