By Tim Binnall
A new study examining the mysterious interstellar object known as 'Oumuamua' suggests that the curious celestial interloper was likely just a comet. Since first being discovered back in 2017, the oddly-shaped 'visitor' has been the subject of considerable speculation among scientists with an array of theories being offered for its origin and nature. While Harvard astronomer Avi Loeb made headlines in 2018 with his suggestion that Oumuamua could be an alien probe powered by a solar sail, more prosaic explanations put forward by researchers included an asteroid that was once a piece of a planet or simply a strange comet.
Although the 'comet hypothesis' had drawn skepticism from scientists since Oumuamua did not exhibit the traits expected of such an object, a newly published paper from a pair of astronomers argues that is precisely what the interstellar 'visitor' was. The researchers posit that cosmic radiation heated hydrogen found within the ball of ice which was then accelerated through our solar system when it released the trapped gas. "It's exactly what should happen to interstellar comets," the paper's co-author Darryl Seligman said in a press release, marveling that "we had all these stupid ideas, like hydrogen icebergs and other crazy things, and it's just the most generic explanation."
Although many media outlets have heralded the new paper for having 'solved' the mystery of Oumuamua, as one might imagine, not everyone is convinced of the study's conclusion as Loeb dismissed the findings to the New York Times. "The authors of the new paper claim that it was a water ice comet even though we did not see the cometary tail," he told the newspaper, "this is like saying an elephant is a zebra without stripes." To that end, comet expert Karen Meech told the Times that the idea is "plausible," but stressed that "I’m not willing to say it 'solves' things" and opined that the "smoking gun," in such an instance, would be the spectroscopic detection of hydrogen being emitted from the object.