Ninth planet exists in Solar System, astronomers conclude

There is another planet in the solar system four times the size of Earth far beyond the orbit of Pluto, astronomers at California Institute of Technology (Caltech) have concluded.

The scientists have not laid eyes on what has been dubbed ‘Planet Nine,’ but said it must exist based on the unusual orbits of icy objects in the Kuiper Belt, the region outside Pluto.

"We saw a strange signal in the data that meant something odd was going on in the outer solar system," Caltech's Mike Brown told the Guardian.

"All of these distant objects were lined up in a weird way and that shouldn’t happen. We worked through the mundane explanations, but none of them worked out."

This new planet varies from 15 and 75 times further from the Sun than the dwarf planet Pluto.

The Earth orbits the sun in 365 days and Pluto takes 248 years for a single orbit, but for Planet Nine it would take 20,000 years.

Caltech has concluded the planet is icy and ten times heavier than Earth.

The next step is actually finding it, but astronomers believe that process should take less than five years.

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