Washington, Oct 13 (PTI) The yet-to-be discovered 'PlanetNine' may be 10 times the mass of the Earth and 20 times awayfrom the Sun than Neptune, a study suggests.
According to researchers, Planet Nine could turn out tobe our solar system's missing 'super Earth' - a planet with amass higher than the Earth's, but substantially lower thanthe masses of ice giants Uranus and Neptune.
The signs so far are indirect, mainly its gravitationalfootprints, but that adds up to a compelling case, they said.
"There are now five different lines of observationalevidence pointing to the existence of Planet Nine," saidKonstantin Batygin, a planetary astrophysicist at CaliforniaInstitute of Technology (Caltech) in the US.
"If you were to remove this explanation and imaginePlanet Nine does not exist, then you generate more problemsthan you solve. All of a sudden, you have five differentpuzzles, and you must come up with five different theories toexplain them," said Batygin.
Six known objects in the distant Kuiper Belt, a region oficy bodies stretching from Neptune outward towardsinterstellar space, all have elliptical orbits pointing inthe same direction, researchers said.
However, these orbits also are tilted the same way, about30 degrees "downward" compared to the pancake-like planewithin which the planets orbit the Sun, they said.
Computer simulations of the solar system with Planet Nineincluded show there should be more objects tilted withrespect to the solar plane.
The tilt would be on the order of 90 degrees, as if theplane of the solar system and these objects formed an "X"when viewed edge-on.
Caltech graduate student, Elizabeth Bailey, showed thatPlanet Nine could have tilted the planets of our solar systemduring the last 4.5 billion years.
In the study published in the Astronomical Journal,researchers wondered why the plane in which the planets orbitis tilted about 6 degrees compared to the Sun's equator.
"Over long periods of time, Planet Nine will make theentire solar-system plane precess or wobble, just like a topon a table," Batygin said.
The last telltale sign of Planet Nine's presence involvesthe solar system's contrarians: objects from the Kuiper Beltthat orbit in the opposite direction from everything else inthe solar system, researchers said.
Planet Nine's orbital influence would explain why thesebodies from the distant Kuiper Belt end up "polluting" theinner Kuiper Belt, they said.
"No other model can explain the weirdness of these high-inclination orbits," Batygin said.
"It turns out that Planet Nine provides a natural avenuefor their generation. These things have been twisted out ofthe solar system plane with help from Planet Nine and thenscattered inward by Neptune," said Batygin. PTI SARSAR.
This is unedited, unformatted feed from the Press Trust of India wire.