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New Trans-Neptunian Object Sparks Planet 9 Theories

5/23/2025

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Summary

Story summary

On May 21, 2025, the International Astronomical Union unveiled the intriguing minor planet 2017 OF201, a colossal trans-Neptunian object measuring between 290 and 510 miles across. Its astonishing orbit, stretching an incredible 838 AU from the Sun, raises questions about the elusive Planet 9, as its path diverges from the expected clustering of distant celestial bodies.

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Story summary

On May 21, 2025, the International Astronomical Union unveiled the intriguing minor planet 2017 OF201, a colossal trans-Neptunian object measuring between 290 and 510 miles across. Its astonishing orbit, stretching an incredible 838 AU from the Sun, raises questions about the elusive Planet 9, as its path diverges from the expected clustering of distant celestial bodies.