10:13 November 7 2018.
(Updated 11:55 November 7 2018)
An object between cigar-shaped stars that fly through the sun may not be a foreign spacecraft, scientists say, despite suggestions from researchers from Harvard University.
Scientists have tried to find out the 1,312ft (400m) object named Oumuamua probably after it was first discovered by telescope in Hawaii in October 2017.
Flat objects, elongated shapes and reddish colors come from outside our solar system, according to the researchers.
It moves at 59,030 mph when it was first tracked by scientists, and unusual trajectories and high speeds make it apart from other celestial bodies such as asteroids and comets.
Earlier this week, Harvard researchers suggest it was "probably an operational investigation completely sent intentionally to around the Earth by alien civilization".
Speaking to AFP, a number of astronomers have challenged the advice of Harvard scientists.
"Like most scientists, I would love to be there convincing evidence of alien life, but this is not it," said Dr. Alan Fitzsimmons from Queens University Belfast.
"It has been shown that observed characteristics are consistent with the body such as comets which are excluded from other star systems.
"And some of the arguments in this study are based on numbers with great uncertainty."
Another well-known astrophysicist, Dr. Katie Mack from North Carolina State, criticized the claim on Twitter.
"The thing you have to understand is: scientists are very happy to publish strange ideas if they even have the smallest part of the possibility of being wrong.
"But until every other possibility has run out tens of times, even the writers might not believe it."
In a letter in The Astrophysical Journal Letters, Dr. Shmuel Bialy and Dr. Avi Loeb claimed that Oumuamua could be a spacecraft driven by light falling on its surface – a theoretical form of space transportation known as a "light screen".
AFP asked Dr. Bialy does he trust his claim. He acknowledged: "I will not say I & # 39; believe & # 39; it was sent by aliens, because I am a scientist, and not a believer, I rely on evidence to propose possible physical explanations for observed phenomena."
Dr Loeb, who is chairman of the Harvard astronomy department, told NBC News: "It's impossible to guess the purpose behind Oumuamua without more data."