A 23-year game of celestial hide and seek may have just ended
In short: For years, Planet Nine existed only as a mathematical ghost—an invisible weight pulling on the edges of our solar system. Now, by comparing two infrared maps taken over two decades apart, astronomers may have finally spotted a physical candidate moving through the deep dark.
The hunt for Planet Nine began in 2016 when astronomers Konstantin Batygin and David Brown proposed its existence to explain strange orbital patterns. They noticed that several trans-Neptunian objects—icy bodies beyond Neptune—were clustered in unusual ways, suggesting the gravitational influence of a massive, unseen body orbiting at an extreme distance from the Sun.
To find it, researchers needed a long timeline. Because Planet Nine is expected to move very slowly (approximately 3 arcminutes per year), traditional short-term observations are ineffective. A team led by Terry Long Phan utilized a unique dataset: infrared all-sky surveys from two different satellites—IRAS and AKARI—taken 23 years apart. This massive gap in time allowed them to detect the subtle shift of an object moving across the sky.
By analyzing the AKARI Far-Infrared Monthly Unconfirmed Source List, which is specifically designed to find faint, moving objects, the team identified 13 candidate pairs. These candidates were estimated to be between seven and 17 Earth masses, located at heliocentric distances of 500–700 AU. One specific pair stood out as a strong candidate because it showed an angular separation consistent with the expected movement of a massive planet orbiting far beyond Neptune.
While this represents a significant breakthrough in identifying a potential physical source for the theory, it remains a candidate based on positional and flux criteria. The discovery relies on the object moving precisely 47 arcminutes across the sky during that 23-year window, matching the predicted motion of a world that has remained theoretical since Pluto's demotion in 2006.
theme perspective mood curious
difficulty 2 topics [ astronomy
space-exploration planet-nine
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- Summary by Intellect · source: Is This Finally The First Hint Of Planet 9?
- Also: Is this the first hint of Planet Nine?
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