“Dwarf” planet at the edge of the solar system, US researchers claim to have discovered

For years, scientists have been searching for the elusive “ninth planet.” Recently, however, they believe they may have identified a new dwarf planet at the edge of our solar system.

The icy bodies located in the Kuiper Belt, beyond Neptune, appear to share a common orbital path. Two decades ago, astronomers posited that this behavior was influenced by the gravitational force of a “ninth planet,” potentially ten times the mass of Earth and previously unseen.

In their investigation of this elusive object, three American astronomers have proposed a new “candidate” for the title of “dwarf planet.” Named 2017 OF201, the object measures approximately 700 kilometers in diameter, as indicated by a preliminary study published last week, awaiting further analysis by other experts. Though it is three times smaller than Pluto, it qualifies as a “dwarf planet,” according to lead author Shihao Cheng from the New Jersey Institute for Advanced Studies in the US, in an interview with Agence France-Presse.

This object orbits at three times the distance from Earth compared to Neptune. Its highly elliptical orbit allows it to extend as far as the Oort cloud, at the far reaches of our solar system, approximately 1,600 times the distance from Earth to the Sun. During its 25,000-year orbit, 2017 OF201 can only be observed from Earth about 0.5% of the time, or roughly once every century.

“It’s becoming increasingly elusive,” noted Cheng, who emphasized that this discovery suggests there may be “many hundreds of similar objects in similar orbits” within the Kuiper Belt.

Researchers are now seeking additional observation time for the James Webb, Hubble, and Alma telescopes to study this new find.

Interestingly, a 23-year-old amateur astronomer from California, Sam Dean, has already tracked the dwarf planet using historic databases. “In my view, OF201 is one of the most fascinating discoveries in our solar system in a decade,” he stated in an interview with Agence France-Presse.

Pluto was initially discovered in 1930 and was considered the “ninth planet” for many years. However, in 2006 it was reclassified as a dwarf planet due to its smaller size—smaller than our Moon. The solar system now includes four other known dwarf planets: Ceres, Eris, Haumea, and Makemake.

Upon studying the orbit of 2017 OF201, researchers found that its path does not align with that of other Kuiper Belt objects, which raises questions about the existence of a ninth planet. Cheng emphasized that more data is required to clarify this issue.

This “astonishing discovery” and similar findings indicate that the original theory of a ninth planet may be fading, as highlighted by Samantha Lauer, a researcher from the University of Regina in Canada.

“We live in a time when powerful telescopes can nearly reach the edge of space,” Cheng noted, adding that “our own backyard” remains filled with mysteries. He is hopeful that the upcoming Vera Rubin Observatory, set to open this year in Chile, will provide some answers.