Interstellar Object 'Oumuamua Is Not an Alien Craft, But a Rock That Was Passing Hydrogen

New research suggests that 'Oumuamua's bizarre behaviors may have a reasonable explanation that is not connected to extraterrestrial life.

'Oumumua: Interstellar Mystery

Live Science reports that the strange interstellar object is the first one found in the solar system that is from outside of it. It has left many scientists and specialists puzzled.

'Oumuamua was first thought to be an asteroid, as reported by Space. Later on, it was suggested to be a comet, while others even thought of it as a potential alien craft.

Live Science notes that the object had the shape of a cigar and that it was 1,300 feet long and probably 10 times thinner compared to its length, as noted by NASA.

The mysterious interstellar object blazed through the solar system in late 2017. In its brief visit to the system, the object had an approach with the earth. It was roughly around 15 million miles away, which is equivalent to 62 distances between the earth and the moon. 'Oumuamua then disappeared after a few months.

Hydrogen Molecule Releases

Now, a new study published in the Nature journal sheds more light on this cosmic mystery. Jennifer Bergner, the lead author of the study and a chemist from the University of California, Berkeley, mentioned to Live Science that molecules of hydrogen trapped inside the ice under the object's surface could have been expelled by the object as the sun warmed it. This may have slightly slowed the object's flight across the sun. Such molecules would not have been observable in prior observations.

As mentioned earlier, the interstellar object was thought to be a comet or asteroid. It could not be confirmed as a comet, however, because it did not release a tail or cloud of gas or dust as it neared the sun. It could have passed an asteroid if it did not have mysterious speed changes when it was close. Several studies have tried to shed light on these observations. However, none were able to do so without specific and unlikely scenarios of formation.

There were hints that a light molecule, such as hydrogen, could drive the movement of objects such as 'Oumuamua. Bergner and Darryl Seligman, a co-author of the study and postdoctoral researcher from Cornell University, demonstrated the possibility of trapped hydrogen being a potential reason for the speed.

As per Live Science reports, they discovered that 'Oumuamua had the capacity to contain the right amounts of hydrogen to do this. In such a scenario, the object came to be in a distant planetary system as an object that was ordinary and comet-like. At some point in time, it was free from its system and started its lengthy journey through the cosmos, which is where cosmic rays hit the water that was trapped inside its body and led to the release of hydrogen atoms. These atoms later recombined to form hydrogen molecules.

Such molecules stayed trapped in the ice pockets of the object. In extremely cold temperatures, these have structures that are disorganized and glass-like. As the interstellar object moved through the earth's relatively warm solar system, the ice started becoming slightly more organized. As it was doing so, hydrogen got released in sufficient quantities to propel the object minimally against the gravity of the sun.

Marco Micheli, an astronomer at the Near-Earth Object Coordination Center of the ESA who did not participate in the study but wrote an editorial about the endeavors, mentions how the explanation does make sense. Micheli notes that it could be the most consistent model to date that explains observations of 'Oumuamua without requiring any far-off explanations.

Though the object is forever gone, Seligman hopes that other visitors from outside can be picked up soon. This will help astronomers look for answers and offer a window for other solar systems across the Milky Way galaxy.

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