Astronomers claim to have found evidence that suggest a planet four times the size of earth may be skirting the edges of the solar system beyond Pluto.
The planet, which is too distant to be easily spotted by earth-based telescopes, could be gravitationally tugging on small icy objects past neptune, helping explain the mystery of those objects’ peculiar orbits, the scientists said.
The claim comes from Rodney Gomes, a noted astronomer at the National Observatory of Brazil in Rio de Janeiro, who presented his computer models suggesting the existence of the distant planet at a meeting of the American Astronomical Society in Timberline Lodge recently.
Astronomers who attended the talk found Gomes’ arguments compelling, but said much more evidence is needed before the hypothetical planet can be said as real, LiveScience reported.
For many years, scientists have observed that a handful of the small icy bodies that lie in the so-called “scattered disc” beyond the orbit of the planet neptune, including the dwarf planet sedna, deviate from the paths around the sun that would be expected based on the gravitational pulls of all the known objects in the solar system.
Sedna, for example, swings around the sun in an extremely elongated orbit — tracing out a very long oval. However, when Gomes ran the calculations with the addition of gravitational pull of a massive planet at the outskirts of the solar system, sedna and the other anomalous objects’ expected orbits fell in line with observations. The unseen planet would be too far away to perceptibly perturb the motions of earth and the other inner planets, but close enough to the scattered disc objects to sway them. Several planet types could fit the disturbances seen in Gomes’ calculations. For example, a neptune-size planet orbiting 225 billion kilometres away from the sun would influence the anomalous objects in the observed manner.