Planet nine mystery deepens as new discovery challenges hidden planet theory
New research is challenging the long-standing theory of 'Planet Nine,' a hypothetical massive planet in the outer Solar System. Scientists are re-evaluating the gravitational anomalies in the Kuiper Belt that originally led to the theory's proposal.
Why it matters
This research impacts our fundamental understanding of the architecture and formation of our Solar System.
Is there a massive undiscovered planet on the outer reaches of the Solar System? The idea has been around since before the discovery of Pluto in the 1930s. Labelled as planet X, prominent astronomers had put it forward as an explanation for Uranus's orbit, which drifts from the path of orbital motion that physics would expect it to follow. The gravitational pull of an undiscovered planet, several times larger than Earth, was seen as a possible reason for the discrepancy.
The article provides a balanced overview of a scientific debate without favoring one theory over the other.
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