But Harvard's research team says they're not giving up hope that it's a sign of alien life: they "follow the maxim of Sherlock Holmes: When you have excluded the impossible, whatever remains, however improbable, must be the truth". There are probably "thousands of interstellar 'Oumuamua-like" objects "trapped" somewhere in the solar system, they wrote.
"This is the only other explanation we could come up with", said Avi Loeb, chair of Harvard's department of astronomy.
It sped past Earth and looped around our sun at 196,000 miles per hour and was about half a mile long.
"'Oumuamua' may be a fully operational probe sent intentionally to Earth vicinity by an alien civilization", researchers at the Harvard Smithsonian Center for Astrophysics wrote in a new study.
A "unique object" was discovered travelling at 196,000 miles per hour on October 19, 2017 by the Pan-STARRS 1 telescope in Hawaii. "Lightsails with similar dimensions have been designed and constructed by our own civilization", an excerpt from the paper read.
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It was opposed by internet companies like Facebook Inc, Amazon.com Inc and Alphabet Inc, which have said the repeal could lead to higher costs.
The object's "excess acceleration" when it travelled through our solar system and its peculiar trajectory distinguishes it from comets and asteroids, the researchers explained.
Comets, in particular, are known to speed up due to "outgassing", a process in which the sun heats the surface of the icy comet, releasing melted gas.
Despite the Harvard researchers' work, most scientists, NBC News says, are urging caution in assuming there's any other civilization beyond Earth's atmosphere - and that it's actively seeking us out.
"Because I am a scientist, not a believer, I rely on evidence to find possible physical explanations for observed phenomena".
"Not 'where is the lack of evidence so that I can fit in any hypothesis that I like?"
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But most people don't take the time to simply read between the lines and that's clearly on them. Just about everybody has an opinion on my life & anxious about what I'm doing.
The study, which was posted online earlier this month, suggests that Oumuamua's unusual "excess acceleration" could be artificial in nature, as it has been implied that it is not an active comet.
Jackson said the spectral data from 'Oumuamua looks like an asteroid or a comet, while that of a solar sail would look very different.
"Why send a spacecraft which is doing this?" he said.
"Its origin could be either natural (in the interstellar medium or proto-planetary disks) or artificial (as a probe sent for a reconnaissance mission into the inner region of the solar system)".
They proposed that it was powered along by "solar radiation pressure" produced by the sun, but went on to make more "exotic" suggestions to explain its acceleration.
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It will also feature the first Native American women, the first Muslim women and the youngest woman ever elected to Congress . We'd been hearing for months about the record number of women running for office, and last night, voters turned out for them.
Oumuamua has left the solar system and is no longer visible, the news outlet noted. In order for it to be effective, Oumuamua needs to be less than a millimeter in thickness, like a sail.