According to Jennifer Bergner, whatever the origin of Oumuamua, it is a water-rich, comet-like object. During his journey through interstellar space, he was subjected to cosmic rays which bombarded the water releasing the hydrogen, which became trapped in the body of the object.
As the bolide approached the Sun, the heat then released the trapped hydrogen, acting as a “thruster” which sent him on an unexpected trajectory.
“Trapped hydrogen is simply the most generic explanation“, develops in a press release Darryl Seligman, of Cornell University and co-author of the study.
These jobs “undoubtedly provide the first explanation, simple and realistic, of the particularities of this object“, commented for his part Marco Micheli, astronomer at the European Space Agency (ESA).