Was 'Oumuamua A UFO?
Last fall, 'Oumuamua (meaning: a messenger from afar) zipped through the inner Solar System. It was first spotted by astronomers at the Panoramic Survey and Rapid Response System (Pan-STARRS) in Hawaii in October. 2017.
'Oumuamua is the first ever confirmed interstellar object in the Solar System. Scientists are yet to pinpoint where exactly in the universe the passerby has come from and identify the circumstances that led it to travel the cosmos.
However, Avi Loeb and colleagues have proposed an idea: 'Oumuamua might actually have been an alien spacecraft. The chair of the astronomy department at Harvard authored a new study that explains their crazy hypothesis that answers why the interstellar object was, in many ways, extraordinary.
"That is a prejudice that we shouldn't have," Loeb told Space. "Science should be open-minded."
'Oumuamua Continues To Baffle
Loeb and his colleagues have so many reasons why they would think 'Oumuamua is an alien spacecraft that visited the solar system. For one, its shape is unique from anything that anyone has seen before. Because it was traveling so fast, scientists had not been able to capture a resolved image of the object before it flew out of the solar system.
Its measurements at 1,300-feet long and 30-feet wide suggest that it is extremely long and narrow, much like a cigar. However, no one knows what it looks like.
Scientists also classified the object as a comet but because of its lack of tail, they reclassified it as an asteroid. Then, earlier this year, another study argued that 'Oumuamua is actually a comet after scientists detected nongravitational acceleration that might have resulted from cometary outgassing.
However, Loeb argued that cometary outgassing would have altered the object's rotation period, something that can easily be identified by astronomers on Earth.
Sailing To The Sun
In the study that will be published in The Astrophysical Journal later this month, Loeb and team presented two possibilities: 'Oumuamua is a light sail that was ejected from an advanced technological equipment created by an intelligent alien race or it is a probe that was meant to check out the solar system.
There is a possibility that 'Oumuamua is an alien space probe. The study pointed out that the visitor's discovery alone was an anomaly because it was among the million other interstellar objects ejected by stars in the Milky Way. In addition, its motion is almost in line with the average motion of material in this region of the galaxy like it was trying to blend in.
"If I created an instrument whose identity I would like to hide, I would put it at the local standard of rest," Loeb added.
The study is now free to read in the online preprint website arXiv.org.