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Alien theory is ‘wild speculation,’ says astronomer who found strange interstellar object

This handout image of artist's impression released by the European Southern Observatory shows the first detected interstellar asteroid, Oumuamua.
This handout image of artist's impression released by the European Southern Observatory shows the first detected interstellar asteroid, Oumuamua. M. Kornmesser/AFP/EUROPEAN SOUTHERN OBSERVATORY

Harvard researchers’ suggestion that a strange interstellar object that invaded our solar system could have been an artificial object built by an alien civilization drew a lot of attention worldwide, but the truth is a little less exciting, the researcher who discovered the object said.

“Honestly, I think it’s a bit of wild speculation,” astronomer Robert Weryk told Canada’s CBC. “We actually think that’s not true based on the data that we obtained.”

Instead, he said, “I think it’s actually just a remnant from another solar system. . . . It’s just a remnant of a comet from a distant solar system, but we have no idea which one. It’s just something that happened to run into us.”


The object ‘Oumuamua — Hawaiian for “messenger from afar arriving first” — is the first ever observed intruding in the orbits of our planets. It was picked up by telescopes in October 2017 at the University of Hawaii’s Haleakalā Observatory. It is now on its way out of the solar system and expected to never return. Scientists say other “interstellar” objects may have sailed by in the past, undetected.

A new paper written by professor Avi Loeb, chairman of astronomy at Harvard, and postdoctoral researcher Shmuel Bialy, suggested the object might be a light sail, or solar sail — a proposed method of powering spacecraft that uses a sail to catch radiation pressure and propel the spacecraft, just as a normal sail uses the wind to propel a boat.

The paper suggests the light sail theory because, Loeb said last week, the object has unexplained excess acceleration like a comet, which gets propelled when ice on it vaporizes. ‘Oumuamua had no tail like a comet, however, Loeb noted.

Weryk said he believes the object is a comet with a “small amount of outgassing that wasn’t visible directly from the ground. That’s why it didn’t appear to be a comet.”


Other researchers have also sounded notes of caution. Steven Beckwith, a professor of astronomy and director of the Space Science Laboratory at the University of California, Berkeley, last week said, “The evidence for a light sail from some distant civilization is too weak to make a convincing case, but it is, nevertheless, fun to think about.”

“I think a lot of people like to consider exotic possibilities. It really opens more questions of ‘What if?’ But for this particular case, I think the data clearly states that this is a natural object. There’s no reason to think it’s anything but that,” Weryk told CBC.

Loeb said Tuesday in an e-mail, “Our paper follows the standard scientific methodology: an anomaly is observed in data, the standard explanation fails to explain it and so an alternative interpretation is proposed. I encourage anyone with a better explanation to write a paper about it and publish it. Wrong interpretations can be ruled out when more data will be released on ‘Oumuamua or other members of its population in the future.”

“The nature of ‘Oumuamua will not be dictated by a popularity contest on Twitter. It is what it is, and the sarcasm expressed by critics is irrelevant,” he said.

Martin Finucane can be reached at martin.finucane@globe.com