Scientists are baffled over a mysterious space object known as "Oumuamua". Some researchers even think it could be an alien spacecraft.
'Oumuamua looks like a long, cigar-shaped asteroid, the size of a large stadium. Researchers say its size, shape, movement, and trajectory are unusual and came from outside the solar system.
In an upcoming research papers, two Harvard scientists theorize that Oumuamua "may be a fully operational probe" sent to Earth by an "alien civilization".
Of course, other scientists think the truth is a lot more boring, and say the Oumuamua is likely a comet or asteroid.
Do you believe in aliens? What's your theory for the Oumuamua?