When astronomers first spied a mysterious cigar-shaped object speeding past the sun last October, they could tell from its path that it had come from another star system but they didn’t know exactly what it was.
The space rock named ‘Oumuamua’ was the first known interstellar object to visit our solar system, and made headlines around the world in 2017.
A study published on Wednesday in the journal Nature indicates that the interstellar visitor, dubbed Oumuamua, is neither an asteroid nor an alien spacecraft but a small interstellar comet also known as a hydrogen iceberg.
What’s more, there might be many more of them out there, forming in the dense cores of molecular clouds throughout our Milky Way galaxy, the researchers suggest.
The researchers believe that the idea that it’s a block of hydrogen ice could explain many of the weird properties that led scientists to label it a possible alien spacecraft.
Professor Gregory Laughlin of Yale said, “We developed a theory that explains all of ‘Oumuamua’s weird properties.
“We show that it was likely composed of hydrogen ice. This is a new type of object, but it looks like there may be many more of them showing up, going forward.”
Researchers at the University of Hawaii first discovered ‘Oumuamua in 2017, but as ‘Oumuamua hurtled through the inner part of the solar system, astronomers noticed it had several unusual properties.