'Oumuamua isn't an alien spaceship — it's a rock that's farting hydrogen, new study suggests

Some of the odd behavior of the interstellar object may be explained by the emission of hydrogen from 'Oumuamua.

According to recent study, there may be a plausible explanation for the strange motions of the interstellar object 'Oumuamua that excludes the existence of sentient extraterrestrial life.

When scientists noticed the odd interstellar guest speeding away from the sun's gravitation, they discovered a scientific riddle. This object was the first extrasolar object ever identified in our solar system. 'Oumuamua was not a comet, which is why it did not exhibit the strange acceleration that comets do when the sun begins to warm the ice inside of them. Some commenters even speculated that 'Oumuamua might be an alien ship in response to the riddle.

However, a recent research that was released on March 22 in the magazine Nature offers a less interesting explanation: It's possible that as 'Oumuamua warmed from the sun, hydrogen molecules trapped in the ice beneath its surface were released, causing a small slowdown in its journey past the sun. According to main research author Jennifer Bergner, a chemist at the University of California, Berkeley, these hydrogen molecules would not have been visible in scientists' observations of 'Oumuamua.

'Oumuamua was first spotted in October 2017 and was visible through a telescope for about four months before disappearing quickly. Due to its peculiar characteristics, it created quite a stir during that brief time. According to NASA, the cigar-shaped object was approximately 1,300 feet (400 meters) long and possibly 10 times skinnier than that.When it first neared the sun, scientists believed it might be a comet, but it did not develop a tail or emit a dust or gas cloud.

If not for the mysterious shifts in speed that the researchers noticed when it was close by, it might have been mistaken for an asteroid since these space rocks move only under the effect of gravity.

Numerous studies have attempted to explain both of these findings, but none have been able to do so without needing extremely precise and improbable formation situations, according to Bergner.

The course of an object like 'Oumuamua, however, may be able to be controlled by a light particle, such as hydrogen, according to some indications. It was modeled by Bergner and her co-author Darryl Seligman that hydrogen confined inside 'Oumuamua might be the cause of the object's acceleration. Seligman is a postdoctoral scholar at Cornell University.

They discovered that the device was capable of holding sufficient hydrogen to carry out their plan. In this situation, 'Oumuamua was created as a typical comet-like particle in a distant planetary system. It broke free from its home system hundreds of millions of years ago and set out on a lengthy voyage through interstellar space. While traveling through this region, cosmic radiation struck water that was imprisoned inside of it and released hydrogen atoms, which then joined to form hydrogen molecules.

The ice in 'Oumuamua, which has an amorphous, glass-like structure at the extremely low temps of interstellar space, continued to contain these hydrogen molecules imprisoned within pockets. This ice started to take on a slightly more ordered structure as 'Oumuamua moved through the relatively mild environment of our solar system, as if getting ready to transform into the crystalline ice we are used to on Earth. As it did, enough hydrogen leaked out to give the object a small boost against the sun's gravity.

Astronomer Marco Micheli, who works at the Near-Earth Object Coordination Centre of the European Space Agency in Italy, said, "I think this explanation makes a lot of sense." According to Micheli, who was not involved in the new research but wrote a commentary about the work for Nature, "it's probably the most consistent model so far that fully explains what we observed on 'Oumuamua without the need for any exotic explanation."

According to Bergner, the hydrogen effect most likely affects typical comets that are born in the solar system, but it is unlikely to have an impact on an object's speed or course unless it is very tiny, like 'Oumuamua.

"We can potentially test whether we see outgassing of hydrogen," she said, "if we can find smaller comets from the Oort cloud [at the edge of the solar system] as they are coming in."