Harvard researchers say it’s possible that a mysterious object hurtling through space could be an alien spacecraft sent intentionally to Earth’s vicinity by another civilisation.
Scientists have been puzzling over ‘Oumuamua’ ever since the mysterious object was seen tumbling past the sun in late 2017.
Some experts think its flattened, elongated shape and the way it accelerated on its trajectory through the solar system set it apart from conventional asteroids and comets.
In November, a pair of Harvard researchers will publish a scientific paper in The Astrophysical Journal Letters, raising the possibility that Oumuamua could be a “fully operational probe sent intentionally to Earth vicinity by an alien civilisation.”
The pair say that after careful mathematical analysis that the object could be a spacecraft of the type known in space research circles as a “lightsail.”
Who would have sent such a spacecraft our way — and why?
“It is impossible to guess the purpose behind Oumuamua without more data,” Avi Loeb, chairman of Harvard’s astronomy department and a co-author of the paper, told NBC News in an email. “If Oumuamua is a lightsail,” he added, “one possibility is that it was floating in interstellar space when our solar system ran into it, “like a ship bumping into a buoy on the surface of the ocean.”
Loeb and his collaborator, Shmuel Bialy, a postdoctoral fellow at the Harvard-Smithsonian Center for Astrophysics, acknowledge that the alien spacecraft scenario is an “exotic” idea.
Other space scientists have strong doubts about it and think there may be other, more mundane explanations.
They include Coryn Bailer-Jones, an astronomer at the Max Planck Institute for Astronomy in Heidelberg, Germany:
“In science,” he said in an email, “we must ask ourselves, “Where is the evidence?, not “Where is the lack of evidence so that I can fit in any hypothesis that I like?”
Bailer-Jones, who earlier this year led a group of scientists who identified four dwarf stars as likely origin points for Oumuamua, raised questions in particular about the object’s tumbling motion.
Why send a spacecraft which is doing this?” he said. “If it were a spacecraft, this tumbling would make it impossible to keep any instruments pointed at the Earth. Of course, one could now say it was an accident, or the aliens did this to deceive us. One can always come up with increasingly implausible suggestions that have no evidence in order to maintain an idea.”
But Loeb called the conjecture “purely scientific and evidence-based,” adding, “I follow the maxim of Sherlock Holmes: When you have excluded the impossible, whatever remains, however improbable, must be the truth.”
The truth may be hard to establish, as Oumuamua has left the solar system and is no longer visible even with telescopes.
But, Loeb said, the fact that we’ve observed one interstellar object like Oumuama suggests that others may be out there.”