New Evidence Supports Existence of Planet Nine in Solar System

Scientists have discovered additional evidence supporting the presence of a ninth planet in our solar system, according to a new paper by Caltech researchers Konstantin Batygin and Michael Brown, set to be published in The Astrophysical Journal Letters. The evidence comes from studying the orbits of trans-Neptunian objects (TNOs) that cross Neptune's orbit.

Batygin and Brown, who first proposed the idea of Planet Nine in 2016, focused their analysis on low-inclination TNOs that interact strongly with Neptune. Their simulations show that the observed orbital distribution of these TNOs is consistent with the presence of a hypothetical Planet Nine, which could be a super-Earth or mini-Neptune located about 400 to 800 times farther from the Sun than Earth.

While Planet Nine has not been directly observed, its existence could explain the unexplained "wobble" in the orbits of distant solar system objects. The researchers demonstrate that the observed clustering of TNOs cannot be explained by galactic tides alone, and that the Planet Nine scenario is compatible with the data.

Why this matters: The discovery of a ninth planet would fundamentally change our understanding of the solar system's architecture and formation. It could also lead to the identification of many more previously unknown objects in the outer reaches of the solar system.

The upcoming Vera C. Rubin Observatory is expected to provide more clarity on what lies beyond Neptune and potentially reveal additional evidence for Planet Nine. Batygin and Brown plan to test their findings with a new independent survey, which they hope may even directly detect the elusive planet. "The Vera Rubin Observatory is going to be a real game-changer," said Brown. "It should find thousands of new TNOs and hopefully some of them will have the orbital parameters that point to Planet Nine."

Key Takeaways

• Caltech researchers find evidence for a 9th planet in our solar system
• Proposed Planet Nine could be a super-Earth or mini-Neptune 400-800 AU from Sun
• Planet Nine could explain "wobble" in orbits of distant solar system objects
• Vera Rubin Observatory expected to provide more clarity on objects beyond Neptune
• Researchers plan new survey to potentially directly detect the elusive Planet Nine