Is there a Mars-like 'Planet 9' hidden? Evidences say so!
There are currently eight planets in our solar system; but according to astronomers, there could be many more. Scientists have been looking at the possible existence of 'Planet 9'. However, a recent study suggested there could be yet another planet hiding in the outer edges of our solar system, orbiting the Sun. Read more about the potential ninth planet!
Mysterious planetary mass in icy outskirts of solar system
Scientists at University of Arizona, including Renu Malhotra, said the potential planet could be much closer to the Sun than Planet 9. Its mass could be somewhere between that of Earth and Mars. They found evidence while looking at the orbital planes of Kuiper Belt Objects (KBOs) and observed differences in the objects at outer edges. The study was published in Astronomical Journal.
About the Kuiper Belt
The Kuiper Belt, extending beyond Neptune, comprises icy celestial objects, including Pluto, and debris called Kuiper Belt Objects. It extends to a few hundred Astronomical Units (roughly 150 million km, the distance between Earth and the Sun) and is 50AU away from the Sun. It hosts celestial bodies similar to those found in the inner solar system's asteroid belt located between Mars and Jupiter.
Outer KBOs tilted differently than normal
Most KBOs orbit the Sun with an inclination (tilt) almost equal to the "invariable plane" of our planetary system. However, scientists found that distant KBOs were orbiting with an inclination of 8 degrees away from the invariable plane. This indicated the outer KBOs are experiencing the gravity of some big, unknown mass, which is warping (bending) the outer solar system's average orbital plane.
Study's lead author Kat Volk's statement
Volk, who found the evidence along with Malhotra, stated: "The most likely explanation for our results is that there is some unseen mass. According to our calculations, something as massive as Mars would be needed to cause the warp that we measured."
Why isn't the object found yet?
Scientists said the object was not likely found as they didn't search the entire sky for distant solar system objects. The most likely place for it to hide is the galactic plane, densely packed with stars and usually avoided by solar system surveys. However, there are 30% chances that the potential planet is not of the right brightness and distance.
How big is this potential Planet 10?
The potential planet could be as far as 500-700 AU from the Sun and is predicted to be as massive as ten Earth masses combined. Scientists, however, aren't ruling out the fact that the curious warp could be caused by more than one object.
