Researchers have identified an object about 700 kilometers (700 kilometers) wide that inhabit the freed outer reach of our solar system, which may be referred to as a dwarf plane and stains it as it moves on a highly elongated orbital path around the sun.
The researchers called it one of the most distant visible objects in our solar system and said that its existence indicates that a huge width of space beyond the outermost planet Neptune and a region called Kuiper Belt may not be deserted, as long as thought.
The Kuiper belt is populated by several icy bodies.
Given the name 2017 AF201, the object falls into a category called Trans-Neptunic objects that orbit the sun at a distance beyond Neptune’s distance. The object takes about 25,000 years to complete a single course of the sun compared to 365 days for the ground to do so.
The researchers said that 2017 AF201 was identified in observations of telescopes in Chile and Hawaii spans seven years.
“It is potentially large enough to qualify as a dwarf planet. Its course is very broad and eccentric, which means it experienced an interesting orbital migration path in the past,” said astrophysicist Sihao Cheng of Institute for Advanced Study in Princeton, New Jersey, who led the study with partners Jiaxuan Li and Eritas Yang Princeton, New Jersey.
Its size is estimated to be slightly smaller than Ceres, which is the smallest of the Solar System’s five recognized dwarf planets and has a diameter of approx. 590 miles (950 km). Pluto, the largest of these dwarf planets, has a diameter of approx. 1,377 miles (2,377 km).
The mass of 2017 AF201 is estimated to be approx. 20,000 times less than the earth’s and 50 times less than Pluto’s.
“We don’t know the mold yet. Unfortunately, it’s too far away and it’s a little difficult to solve it with telescopes,” Cheng said. “Its composition is completely unknown yet, but probably similar to other icy bodies.”
The discovery was announced by the smaller planetary center of the International Astronomical Union, an international organization of astronomers, and detailed in a study that was posted on the open research website arxiv. The study has not yet been peer-reviewed.
Earth’s orbital distance from the sun is called an astronomical unit. 2017 AF201 is currently located at a distance of 90.5 astronomical units from the Sun, which means 90.5 times as far as the Earth.
But at the longest point during its orbit, 2017 AF201 is more than 1,600 astronomical units from the sun, while the closest point on its orbit is about 45 astronomical units. This means that it is sometimes closer to the Sun than Pluto, whose orbital distance ranges from 30 to 49 astronomical units as it moves an elliptical path around the sun.
The researchers suspect that the extreme course in 2017 AF201 may have been caused by a long -time close encounter with gravitational influence from a gigantic planet.
“We still don’t know much about the solar system far away because it is currently difficult to see things beyond about 150 astronomical units,” Cheng said. “The presence of this single object suggests that there may be an additional hundred or so other objects with similar lane and size. They are just too far away to be detectable right now.”
The five dwarf planets recognized by the International Astronomical Union are in the order of distance from the Sun: Ceres, which is the largest object in the asteroid belt between Mars and Jupiter, then Pluto, Haumea, Makemake and Eris, all of which orbit over Neptune.
The organization defines a planet and a dwarf plane differently. A planet must circling its host star – in our case the sun – and must mostly be round and sufficiently large for its gravitational strength to clear all other objects of similar size near its orbit. A dwarf plane should circles the sun and mostly be round, but it has not cleared its orbit of other objects.
Cheng said the discovery of 2017 AF201 has consequences for hypotheses involving the potential existence of a ninth planet in our solar system, called Planet X or Planet Nine.
This is because 2017 AF201’s orbit does not follow the pattern exhibited by other known trans-neptunic objects that tend to cling together. Some researchers had assumed that such a cluster was caused by the seriousness of an yet-to-be-discovered planet.
“The existence of 2017 AF201 as an outlier for such clusters could potentially challenge this hypothesis,” Cheng said.
