American planetary scientists have significantly reduced the probability of the existence of the hypothetical ninth planet, commonly referred to as “Planet X,” following an extensive survey of the outer solar system. Utilizing the PAN-STARRS1 telescope in Hawaii, the research team has effectively ruled out Planet X’s presence in approximately 75 percent of the regions where it was previously suspected.

The study, led by Matthew Holman from the Harvard-Smithsonian Center for Astrophysics, represents one of the most comprehensive searches to date for large planetary bodies residing in the distant reaches of the solar system. The findings, which have been published on the preprint server arXiv.org, offer new constraints on the possible location of Planet X and provide an updated understanding of the solar system’s farthest regions.
During the survey, researchers identified 692 small celestial bodies, including 23 dwarf planets and 109 objects that had not been previously cataloged. These discoveries contribute to the growing census of distant solar system objects and help refine models of planetary formation and migration. Despite the extensive detection of smaller bodies, the survey found no evidence of any large planetary object consistent with the characteristics hypothesized for Planet X.
The team employed a specialized algorithm designed to process multiple images of the same sky regions, taken over an eight-year period from 2009 to 2017. This method allowed the scientists to track extremely slow-moving objects located at distances of 80 astronomical units (AU) or more from the Sun. By cross-referencing the positions of known asteroids with well-defined orbits, the algorithm was able to filter out false positives and accurately identify new distant objects.
The absence of any detection of Planet X from the analyzed images has narrowed its potential location to a small and as yet unexplored segment of the sky near the plane of the Milky Way galaxy. This area presents observational challenges due to the dense field of background stars, complicating efforts to identify faint, slow-moving planetary bodies. Further targeted surveys will be necessary to investigate this remaining zone.
Interest in the Planet X hypothesis was revived in 2016 when planetary scientists Konstantin Batygin and Michael Brown presented indirect evidence suggesting the existence of a massive ninth planet. They proposed that unusual orbital clustering among certain distant solar system objects could be explained by the gravitational influence of a Neptune- or Uranus-sized body orbiting the Sun at an estimated distance of around 670 AU, or 100 billion kilometers.
Despite multiple dedicated searches over the years, the hypothesized planet has not been directly observed. The continued lack of confirmation has led some astronomers to question its existence altogether, while others pursue alternative theories to explain the observed gravitational anomalies in the outer solar system. The recent findings further complicate the debate but provide valuable data to refine ongoing investigations into the solar system’s outermost frontier. – By MENA Newswire News Desk.