Scientists have discovered another marker on their way to the supposed planet Nine.
This note is 2015 TG387, a newly found object in the outermost solar system, far beyond Pluto. The 2015 TG387 orbit shares its peculiarities with those of other extremely-colored bodies, apparently shaped by the gravitational force of a very large object in that distant, cold area – the hypothetical planet Nine, also known as Planet X.
"These removed Objects are like breadcrumbs that lead us to Planet X, "said study director Scott Sheppard of the Carnegie Institution for Science in Washington, DC, in a statement. [The Evidence for ̵
"The more we can find, the better we can understand the outer solar system and the possible planet that we think makes its orbits – a discovery that redefines our knowledge of the evolution of the solar system would." He added:
And 2015 TG387 is particularly among these breadcrumbs because it was found during a relatively uniform investigation of the northern and southern skies, rather than a targeted hunt for clustered items in certain parts of the sky, Sheppard said. Targeted hunts can lead to distorted results – such as the appearance of clusters where none exist, he explained.
2015 TG387 has two dwarf planet companions in the low-bias class, Sheppard said: 2012 VP113, which he and his colleague Chadwick Trujillo (who is also a co-author of the new work) discovered in 2014 as part of the same long-term long-term study ; and the relatively bright Sedna (because the whole sky was scanned for its brightness level).
"And then, if you bring in some of the other extreme objects, some of them were also found in our investigation," Sheppard told Space.com. "The statistics are getting better and better than this planet is probably out there."
In 2015, Sheppard and his colleagues discovered the first TG387 in October 2015 with the 8-meter-long Japan Subaru telescope at the Mauna Kea volcanic peak in Hawaii. The researchers called the object "The Goblin" because of the found date and the "TG" in the preliminary designation.
It took the team three more years to pin down the Goblin's orbit. This was done using observations from the Las Campanas Observatory in Chile and the Discovery Channel Telescope in Arizona.
In 2015, TG387 orbits the Sun on an extremely elliptical orbit located at its closest point within about 65 astronomical units (AU) of the Sun (perihelion) and farthest from it about 2,300 AU (aphelion).
An AU is the average distance between Earth and Sun – about 93 million miles (150 million kilometers). So 2015 TG387 is far away. In fact, it takes about 40,000 Earth years for the newly discovered object to complete a lap around the Sun. [Our Solar System: A Photo Tour of the Planets]
Only two known solar system bodies have more distant perihelies than The Goblin (2012 VP113 and Sedna), and only one (2014 FE72) has a larger aphelic space. (For the Perspective: Plutonever gets closer to the sun than 29.7 AU or farther than 49.3 AU.)
Sheppard and his colleagues think that in 2015 TG387 is about 300 kilometers wide and probably spherical. In this case, it would be called a dwarf planet. But that's all they can say about the physical properties of the goblin.
"It's pretty weak, so we can really see it's there," Sheppard told Space.com. "We do not even know the color of the object, we have not received any spectroscopy on the object or anything like that."
(The 186-mile diameter is not a measurement, but an estimate, assuming a "moderate" reflection for 2015 TG387.)
But back to orbit: The goblins are similar to other extremely distant bodies – especially in an element called "perihelion longitude". In essence, the elongated parts of their elliptical orbits are grouped in the same part of the sky, which coincides with the gravitational motion through Planet X.
The existence of Planet X in 2014 was seriously seriously proposed by Sheppard and Trujillo for the first time, explaining curiosities in the 2012 VP113, Sedna and some other trans-Neptune objects.
In 2016 astronomers Konstantin Batygin and Mike Brown presented further evidence of such an invisible "perturber" they called Planet Nine. Batygin and Brown have suggested that this world could be about ten times more massive than the Earth and on average about 600 AU from the Sun.
In the new study, the researchers also performed computer simulations to test how the planet X's gravitational pull was used Could affect orbit of The Goblin. They found significant herder husbandry similar to that found for other distant objects – and found that the 2015 TG387 orbit remains nonetheless stable for the age of the solar system.
"What makes this result really interesting is that Planet X affects the TG387 of 2015 just like any other extremely distant solar system object," said Trujillo, who works at Northern Arizona University, in the same statement. "These simulations Do not prove that there is another massive planet in our solar system, but they are further proof that something big might be out there. "
Sheppard estimates Planet X's existence is 85 percent. And he says that it's not surprising that astronomers have not discovered it yet. It is – hundreds of AU away, if not 1,000 AU – something as big as Neptune would be weaker than most telescopes could see, "Sheppard told Space.com. (If that sounds odd or inappropriate: The goblin was found near the perihelion, about 80 AU away from the sun.)
"And most of our research so far is not going to be so weak, do not go so deep It covers very little from the sky to the depths, which must be covered to find something in that fainting, "he added." You can very easily hide a very big thing in the outer solar system. "
The description the discovery of 2015 TG387 was submitted to the Astronomical Journal
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