After NASA’s spectacular fly-by of Pluto on July 14 with the New Horizons mission, the probe is set on another mission — to discover the mysterious Planet X in the Kuiper Belt. While the probe is being sent to investigate, it is basically a large icy rock, about the size of the district of Columbia.
Scott Sheppard, an astronomer at the Carnegie Institute of Washington said that astronomers have so far detected about 1,500 icy bodies in the Kuiper Belt, and a few of them are big enough to classify them as dwarf planets. However, some believe that planets larger than the Earth, and gas giants like Neptune could be out in the Kuiper Belt. Astronomers have found hints that the hidden planet could be larger than Pluto or even larger than the Earth.
“I think there definitely bigger things out there bigger than Pluto that are yet to be discovered,” said Sheppard.
However, astronomers are not the only ones proposing the existence of Planet X. Sheppard and Chad Trujillo of the Gemini Observatory, published a report in the journal Nature in 2014, indicating that there could be “pertuber,” or a large gravitationally disturbing object in the edges of the Solar System. Since then, the mysterious planet has become a “holy grail” for astronomers. However, the planet does not produce its own light, and its search has been difficult. But, gravitational signatures suggest that the planet does exist.
The planet follows a key orbital feature known as “argument of perihelion.” Sheppard said that the argument of perihelion is the angle at which an object comes to perihelion with respect to ecliptic plane. Mike Brown, a Caltech astronomer who discovered the dwarf planet Eris said that Scott’s claim is that all of these objects come to perihelion at the ecliptic, and all are going from below the same plane to above the plane at perihelion.[ Via ]