When they saw it for the first time, in October 2017, several telescopes followed their path for three nights until they lost sight of it.
It was not a normal object. It was measured 400 meters, width ten times smaller and the surface was reddish. He quickly turned, had a chaotic trajectory and suddenly changed his light.
Those who first watched it, astronomers Pan STARRS of the Continuous Suspension System, from the University of Hawaii, gave it its name, Oumuamua, which means "the messenger who is the first to arrive" in Hawaii.
Initially, the discussion of what Oumuamua had had was two possible answers: comet or asteroid.
"We've tested many convincing alternatives, and most likely Oumuamua is to be a comet, and the gases that come out of its surface cause small variations in its path," said David Farnochhia, from the Jet Propulsion of the NASA lab.
Others, however, said that it was not a comet because they did not detect the characteristic tail of the tail dust and ice particles that these travelers usually have in the universe.
Dr. Wes Fraser, Queen's University in Belfast, said in February this year his strange movement was probably due to the fact that another object struck him at some point in his history.
Now, a new study by scientists from the Harvard-Smithsonian Center for Astrophysics in the United States says Oumuamua could come up with a natural process "still unknown in interstellar space." [ISM, por sus siglas en inglés] or on protoplanetar disks. "
But the other option they are thinking iswho its origin, perhaps, "artificially".
"Full operational probe"
Speaking of "Artificial Origin", astronomers Shmuel Bialy and Abraham Loeb, authors of a new study published in the Astrophysical Journal Letters, mean that "Oumuamua it can be a fully operational probe deliberately sent to the Earth by a civilized alien".
Or this can be a "piece of advanced technological equipment," especially a solar sail, a device powered by sunlight or solar wind power.
Bialy and Loeb come to this conclusion because of the unusually high speeds and the path telescopes managed to capture from Oumuamua during their three night vision.
"This is the first object discovered in the Solar System that was created outside the Solar System." Since its discovery, Oumuamua has shown unusual characteristics, making it a rare subject, which belongs to the class of an object he has not seen before, "Loeb told BBC.
"What could cause the overcrowding of Oumuamua? This is the fundamental question we are trying to answer, if it is not the tail that pushes it, what else could be? We suggest that it is sunlight." explained the scientist.
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Loeb compares Oumuamu with the solar sails created by our civilization, such as IKAROS, the first solar-powered solar interplanetary probe launched by the Japanese Aeronautical Research Agency (JAXA) on the planet Venus in 2010,
"If (Oumuamua) is a part of a collection of items, we have to be more than we will discover in the future, Only a fraction of the interstellar objects will be the technological remains of extraterrestrial civilization. But we have to examine everything that comes into the solar system from the interstellar space to get to know the true nature of Oumuamou or other mysterious objects, "said the scientist.
Study "fairly incorrect"
"I'm not quite sure and I really believe the study is pretty bad […] Carl Sagan once said: "Extraordinary Demands Demand Extraordinary Evidence" and this document clearly lacks evidence and no extraordinary evidence, "said Alan Jackson, a member of the Planetary Research Center at the University of Toronto. CNN chain.
Jackson believes this If Oumuamua was a solar sailor it would be thinner than what the authors think investigation.
In addition, it confirms that, if it was a ship in the operation "I'd have a much simpler ride and acceleration apparently induced by radiation. "And in case he is damaged, Jackson says his move"will be much more influenced by the radiation power what you see. "
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Bialy and Loeb explained in their article that the telescope observation object "is not convincing enough to give a clear picture of Oumuamua, and one can only speculate about its possible geometry and nature."
"While the periodic variations are observed in the obvious size, there are still too many degrees of freedom – for example, the angle of observation, not uniform reflection, etc. – to clearly define its geometry. "
Alan Fitzsimmons, astrophysicist at Queen's University in Belfast, pointed out this in an AFP interview: "Some of the arguments in this study they are based on numbers with great uncertainties".
In his Twitter account of astrophysicist Katie Mack of the North Carolina University, she said: "Scientists are happy to announce an extravagant idea if they do not have the slightest chance of being wrong, they do not create it until other options are exhausted a dozen times."
Is Oumuamua a proof that life exists on other planets? Loeb responds to this question to the BBC: "I follow Sherlock Holmes's principle:" When you clear any logical solution to the problem, it's unethical, though impossible, it's always true. "
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