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ORBONIX · HYPOTHETICAL WORLD

PLANET X

A hypothetical distant planet proposed to explain unusual orbital patterns among some objects in the outer Solar System.
PLANET X · HYPOTHETICAL
PLANET X HAS NOT BEEN DIRECTLY OBSERVED · HYPOTHETICAL OBJECT
~5–10 M⊕
POSSIBLE MASS RANGE
~400–800 AU
POSSIBLE ORBITAL DISTANCE
HUNDREDS OF YEARS
POSSIBLE ORBITAL PERIOD
UNKNOWN
DIAMETER
UNKNOWN
COMPOSITION
UNCONFIRMED
EXISTENCE
THE SEARCH FOR A HIDDEN WORLD
Planet X is a hypothetical planet that may exist far beyond Neptune. The modern Planet X hypothesis is closely related to the idea of "Planet Nine". Researchers proposed that the unusual orbits of several distant trans-Neptunian objects could be explained by the gravity of a large, currently undiscovered planet. The proposed object would be extremely far from the Sun. Because of this enormous distance, it would receive very little sunlight and would be exceptionally faint from Earth. Scientists have not directly detected Planet Nine, and its existence remains unconfirmed. The search continues using powerful ground-based telescopes and astronomical surveys.
PLANET X FEATURES
GRAVITATIONAL CLUES
The hypothesis is based partly on unusual orbital patterns observed among distant objects beyond Neptune.
EXTREME DISTANCE
If it exists, Planet Nine would orbit hundreds of astronomical units from the Sun, far beyond the known planets.
NOT DISCOVERED
No telescope has yet produced a confirmed direct observation of the proposed planet.
DID YOU KNOW?
If Planet Nine exists, it could be farther from the Sun than any known planet in our Solar System.
CONCEPTUAL VISUALIZATION · PLANET NINE
ORBONIX · SOLAR SYSTEM