Evidence of a still-undiscovered planet, called Planet Nine or Planet X by scientists, has been mounting for some time, and a newly-discovered object far out from the Sun may be the latest piece to the growing puzzle.
Science Magazine says that the discovery of the tiny dwarf planet was "a lucky one", as its elliptical orbit takes some 40,000 years to travel around the sun. It takes about 40,000 years for a complete walk around the Sun (its year) and 99% of this time is too light to be seen from Earth. For context, Pluto's distance is around 34 AU, so 2015 TG387 is about two-and-a-half times further away from the sun than Pluto is right now.
While "Planet X" is still theoretical, this new body found beyond Pluto has been confirmed in the annoucement by the International Astronomical Union's Minor Planet Center, which is responsible for locating minor bodies in the solar system.
A scrawny dwarf planet nicknamed the Goblin has been discovered well beyond Pluto.
'The more of them we can find, the better we can understand the outer Solar System and the possible planet that we think is shaping their orbits - a discovery that would redefine our knowledge of the Solar System's evolution'.
The simulations showed why the most-distant objects in our Solar System have similar orbits that keep them from ever approaching the proposed planet too closely. "We are only seeing the tip of the ice berg", Sheppard said in an email.
The existence of a space object had been predicted in 2015. A full report has been submitted to The Astronomical Journal.
The researchers were able to detect the Goblin in the first place because they're using the Japanese Subaru telescope on Mauna Kea in Hawaii, one of the largest telescopes in the world and the most powerful survey telescope due to its large field of view.
Only a few known objects in our solar system have comparable orbits, such as dwarf planets 2012 VP113 (nickname: Biden) and Sedna. But the planet may be most memorable for another discovery it portends. But with each new find, astronomers come that much closer to finding their mystery planet.
It is "about 300 kilometers in diameter, on the small end of a dwarf planet", according to astronomer Scott Sheppard, of the Carnegie Institution for Science in Washington. "These simulations do not prove that there's another massive planet in our Solar System, but they are further evidence that something big could be out there" Trujillo concludes.
"We think there could be thousands of small bodies like 2015 TG387 out on the solar system's fringes, but their distance makes finding them very hard", said the University of Hawaii's David Tholen, a member of the research team. "We are only just now uncovering what the very outer solar system might look like and what might be out there".
"We think there are thousands of these, and a lot of them are too distant to detect", Sheppard said.
The team will begin a new run of observations in November, with the hope of finding more objects, possibly including the elusive Planet Nine.
The existence of a Ninth planet was not recorded directly.
In 2016, Michael Brown and Konstantin Batygin of the California Institute of Technology, published a detailed prediction of what they called an unseen planet, bigger than Earth yet smaller than Neptune, that was shepherding the movement of these distant worlds and could explain the odd journeys around the sun of these faraway worlds.