The Elusive “Planet Nine” Could Be An Adopted Solar System “Family Member”
Even though we have several spacecraft scouring the solar system let and right, there are still plenty of mysteries still to be had. And there’s no bigger mystery out there than the elusive “Planet Nine”. This is a hypothetical world, part of our solar system, but which orbits the sun, close to the Oort cloud. The proposed distance between it and the sun is somewhere around 1,000 AU (Astronomical Units) where 1 AU is the relative distance between Earth and the sun. Another frame of reference could be Pluto, which is on average at about 39.5 AU from the sun.
Nevertheless, we call this planet “hypothetical” because nobody was actually able to see it. It would seem counterintuitive in this day and age to say that we can’t see an entire planet in our own solar system, all the while we’re observing exoplanets in other solar systems, thousands of light years away. But it is true. The reason for it is that we can see things that emit light, like a star, but non-light-emitting objects are really hard to see; like a planet, or an asteroid heading towards Earth.
But even if we can’t see it, it is believed to be there, largely because one such planet could explain the improbable orbital configuration of objects beyond Neptune. However, a planet that size existing so far from the sun is quite hard to explain. One possible explanation is that it formed closer to the sun, but then due to some gravitational processes during te early life of the solar system, it moved away. It is possible that it was pulled away when our solar system passed close to another one.
A New Theory about the Plant Nine Origins
Researchers from New Mexico State University (NMSU), however, believe that Planet Nine is was not formed here like the other planets, but is rather a “rogue” planet adopted by our solar system. This theory would explain why it orbits so far from the sun.
It is believed that interstellar space is heavily populated by many such rogue planets which have been orphaned by their parent solar systems for one reason or another. And over time, these wandering rogue planets may come across another solar system to which it can attach to. When this happens, chances are that it can destabilise the previous orbital order of the already existing planets, even leading to planetary collisions or flinging other planets into space. There is also the chance that these planets are “peacefully” taken in and “adopted” by its foster solar system.
According to computer simulations, in some 60 percent of cases, the rogue planet is slingshotted back into space, often times taking another planet with it. But if this planet is smaller than the size of Neptune (some 14 bigger than Earth), and its orbit is wide enough, it will result into a gentle assimilation – which may be the case here. Now, according to the interferences seen so far, it would indicate that Planet Nine is roughly 10 times larger than Earth.
However, before all of this is proven or disproven, astronomers need to find it. But, nevertheless, the astronomers at Caltech are confident that 2017 will be the year when they’ll do it. They are relentlessly scouring the skies for the mysterious Planet Nine.