"Once these data are obtained and analysed, astronomers may know more about the origin and possibly composition of the object".
It was moving at 59,030mph when it was first tracked by scientists.
Harvard researchers have now said it "may be a fully operational probe sent intentionally to Earth's vicinity by an alien civilisation". The team termed the possible propulsion system a "lightsail of artificial origin".
According to the new study compiled by Shmuel Bialy and Abraham Loeb, "The large variations in its apparent magnitude and the non-trivial periodicity of the lightcurve, suggest that 'Oumuamua is rotating in an excited spin state (tumbling motion), and has an extreme aspect ratio of at least 5: 1, an unprecedented value for previously known asteroids and comets in the Solar System".
"This would account for the various anomalies of 'Oumuamua, such as the unusual geometry inferred from its light-curve, its low thermal emission, suggesting high reflectivity, and its deviation from a Keplerian orbit without any sign of a cometary tail or spin-up torques". However, he adds that, if Oumuamua is indeed a lightsail, it may have run into our solar system "like a ship bumping into a buoy on the surface of the ocean".
Seth Shostak, a senior astronomer at the SETI (Search for extraterrestrial intelligence) Institute in Mountain View, California, said: "It's certainly ingenious to show that an object the size of Oumumua might be sent by aliens to another star system with nothing but a solar sail for power. So we wrote this paper suggesting this explanation", Loeb told the Boston Globe.
"Not 'where is the lack of evidence so that I can fit in any hypothesis that I like?"
Another scientist, also studying Oumuamua - and who identified four dwarf stars that could be Oumuamua's point of origin - says the object moved too haphazardly to collect any valuable information, even if it was a probe.
Instead, it had dived between Mercury and the sun and was zooming past Earth on its way out of our solar system, a path that meant Oumuamua was an interstellar traveller from beyond the solar system.
"I follow the maxim of Sherlock Holmes: When you have excluded the impossible, whatever remains, however improbable, must be the truth", Loeb said.
A massive flattened boulder-like object traveling through space with "peculiar acceleration" could be an alien craft, according to a new study.
"If radiation pressure is the accelerating force, then 'Oumuamua represents a new class of thin interstellar material, either produced naturally, through a yet unknown process in the [interstellar medium] or in proto-planetary disks, or of an artificial origin".