Scientists found evidence of an unseen planet in the far reaches of our very own solar system. Different from the so-called Planet Nine, the planetary mass hiding in the Kuiper Belt could very well be Earth's closer and smaller cousin.
Hiding In The Kuiper Belt
Searching the universe for distant planets and solar systems has yielded quite amazing results so far. In its on-going missions, humanity has found distant planets, galaxies, and even solar systems that match ours. Although we have yet to travel space aboard the Enterprise, there are other methods or observation that scientists are using to navigate the far reaches of space.
One such observation by Renu Malhotra and Kat Volk from the University of Arizona's Lunar and Planetary Laboratory (LPL) presents evidence of a planetary mass that had been hiding closer to our home. The possibly still unseen mass revealed itself by its effects on the space rocks in the Kuiper Belt.
The Kuiper Belt is home to space rocks, minor planets, icy bodies, and a few dwarf planets residing in the outskirts of our solar system. Often, these Kuiper Belt objects (KBO) orbit the sun with a particular inclination that, Volk and Malhotra discovered, is not followed by the most distant objects in the Kuiper Belt.
In fact, they found that a population of KOBs are tilted away from the invariable plane by eight degrees, which could mean that something is interfering with the orbital plane of the outer solar system — something large enough to cause the warp.
The Warp On Kuiper Belt
Volk believes that the explanation for the warp is an unseen mass, possibly as large as Mars, could have been causing the warp. This could mean that somewhere in the outskirts of the Kuiper Belt lies a large object hiding in plain sight.
Other explanations for the warp could be that it was merely a statistical fluke, but according to Volk and Malhotra's calculations, the average plane really does warp away from the invariable plane, leaving only a 1 to 2 percent chance that the warp is just a fluke.
Another possible explanation for the warp is that a star may have passed near the solar system, causing the warp. However, a passing star's effects on the KBOs would cease once the star has passed, and it would have done so within 10 million years. As such, the authors think this is an unlikely scenario.
Could This Be Planet 10?
Now, this is different from the proposed Planet Nine, which is far larger and more distant than the current mass. Based on observations of Planet Nine, it is likely 10 times more massive than the Earth, and so much farther that it wouldn't have had an effect on the KBOs.
Volk and Malhotra believe that the simple reason for why a much closer object hasn't been seen before is that the planetary mass could have been hiding all this time in the galactic plane, an area that is avoided in solar system surveys because they are so densely packed with stars. Volk and Malhotra calculate the chances of such limitations leading to the delayed discovery to be at 30 percent.
So what happens when they do find it? Will they name it Planet 10, because another proposed planet has already claimed the name of Planet Nine even if it is farther from the solar system? That matter is unclear, but perhaps not that far away once the construction of the Large Synoptic Survey Telescope is complete.