Daily Mail 
October 3, 2018
A mysterious tenth planet really may lie at the edge of the solar system, according to new research.
Astronomers have discovered an object two and a half times further from the Sun than Pluto that adds to evidence of the existence of ‘Planet X’.
It is one of the most distant bodies ever identified within the sun’s gravitational range.
And its unusual orbit supports the theory there is a huge, rocky world ten times bigger than Earth on the outskirts of our star system.
Nicknamed ‘Planet Nine’, the idea first emerged in 2014 when Dr Scott Sheppard and Professor Chad Trujillo sought to explain a strange cluster of six small objects in the Kuiper Belt, a field of icy and rocky objects beyond Neptune.
Their orbits all tilted in the same way, an arrangement that is nearly impossible to generate without the help of some external force.
Dr Sheppard and Prof Trujillo suggested a large planet was lurking in the shadows, warping the orbits of objects that came near.
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