New Dwarf Planet Candidate 2017 OF201 Poses Challenge to Planet Nine Theory.

Science and Technology

In May 2025, a team of scientists from the Institute for Advanced Study, School of Natural Sciences, Princeton, New Jersey (USA), discovered a new Trans-Neptunian Object (TNO) named 2017 OF201. Located beyond the Kuiper Belt in the distant reaches of our solar system, this discovery raises new questions about the widely discussed Planet Nine hypothesis.


      - The object was identified through detailed analysis of astronomical image data from the Victor M. Blanco Telescope in Chile and the Canada-France-Hawaii Telescope.

      - Measuring approximately 700 kilometres (430 miles) in diameter, 2017 OF201 meets the criteria for classification as a dwarf planet—making it about one-third the size of Pluto.

     

Main Point :-   (i) 2017 OF201 has a highly elongated orbit, with an aphelion of over 1,600 Astronomical Units (AU) and a perihelion of 44.5 AU—similar to Pluto’s orbital distance. It completes a single orbit around the Sun in roughly 25,000 Earth years and is visible from Earth for just 0.5% of that time, or about 100 years.

      (ii) This discovery challenges the Planet Nine theory proposed in 2016 by Caltech astronomers Konstantin Batygin and Mike Brown, which suggests the existence of a large, unseen planet influencing the orbits of distant icy bodies.

(iii) However, 2017 OF201's orbit does not align with the clustered patterns expected under this theory, thereby casting doubt on its validity.

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