• Scientists observe the mysterious and sudden acceleration of the Oumuamua comet
• The cosmic object was previously believed to be an alien spacecraft
• Experts theorize that the sudden increase in speed was due to a release of hydrogen gas as the comet received sunlight

Scientists have offered a compelling explanation for the mysterious and sudden acceleration of an alien comet known as Oumuamua, which is the first interstellar object found to visit our solar system.

The comet was first observed in 2017 and has been monitored to undergo a sudden acceleration as it headed toward our sun. Scientists provided various hypotheses in light of the unexpected behavior of the comet. These include fleeting speculation that an alien spacecraft could have traveled through space.

Alien Comet's Acceleration

But a recent study has offered a more compelling explanation, that the comet's speed increase resulted from a release of hydrogen gas as the cosmic object was warmed up by sunlight. The comet lacked a tail of gas and dust that is characteristic of a standard comet.

Scientists previously described Oumuamua as being cigar-like in shape but are now believed to resemble a rocky pancake. The comet was found to be smaller than previously estimated and was given rough sizes of 375 feet by 365 feet and a thickness of roughly 60 feet, as per Reuters.

Furthermore, researchers said that it seemed like the comet was born similarly to others as a planetesimal. This is a small object in the early stages of planet formation and is considered a large, icy space rock.

The team said that after Oumuamua was somehow ejected from the solar system that it was located in, its chemistry changed as it received high-energy radiation while traveling through space. This caused a conversion in some of the comet's ice into hydrogen that became trapped within the rest.

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Oumuamua's Weird Path

The researchers noted that when the comet was warmed up while passing through our inner solar system, some of its surface ice melted away and released the trapped hydrogen gas, giving Oumuamua a little kick to its speed.

A study co-author, Jennifer Bergner, said that comets preserve a snapshot of what the solar system looked like at the time that it was only in its early years. She noted that studying these cosmic objects is a way for scientists to look back in time, according to CNN.

Scientists estimate that Oumuamua arrived at our solar system roughly six years ago, and it was first discovered by the University of Hawaii's Pan-STARRS1 telescope. Its name is Hawaiian and is translated to "a messenger from afar arriving first."

Before the recent theory, scientists spent four months perplexed by Oumuamua's sudden increase in speed and change in trajectory as it slingshotted around our sun. Another co-author of the study, Darryl Seligman of Cornell University, said that Bergner's theory was the most probable reason for the cosmic object's change in behavior, said CBS News.

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