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New Sednoid 'Ammonite' Sparks Planet Nine Speculation

7/25/2025

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Summary

Story summary

Astronomers have unveiled a fascinating new sednoid, affectionately named "Ammonite," lurking beyond Pluto. Ranging from 137 to 236 miles in diameter, its peculiar orbit raises questions about the elusive Planet Nine. This discovery not only sheds light on the solar system's tumultuous history but also emphasizes the immense, uncharted territories that await exploration.

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Story summary

Astronomers have unveiled a fascinating new sednoid, affectionately named "Ammonite," lurking beyond Pluto. Ranging from 137 to 236 miles in diameter, its peculiar orbit raises questions about the elusive Planet Nine. This discovery not only sheds light on the solar system's tumultuous history but also emphasizes the immense, uncharted territories that await exploration.