But scientists now believe the proof of its existence has already been gathered by a Nasa space telescope, Wise, and is just waiting to be analysed.
Whether it would become the new ninth planet would be decided by the International Astronomical Union (IAU). The main argument against is that Tyche probably formed around another star and was later captured by the Sun's gravitational field.
The Independent: http://www.independent.co.uk/news/science/up-telescope-search-begins-for-giant-new-planet-2213119.html"
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