In the cold, distant range of the solar system, far beyond Pluto, astronomers have just found out what a new dwarf planet could be.
It's called 2017 of201A rock that seems to be about 700 kilometers (435 miles) big enough to qualify as a dwarf planet. What makes it even more interesting is its orbit, which implies that there is no huge planet nine, somewhere out there in the dark outer wilderness of the solar system.
“The aphel of the object – the longest point on the orbit of the sun – is more than the 1,600 times that of the earth orbit,” says astrophysicist Sihao Cheng from the Institute for Advanced Study in Princeton, New Jersey. “In the meantime, its perihel – the closest point on its orbit on the sun – is the 44.5 times that of the earth orbit, similar to Plutos Orbit.”
Cheng and his colleagues have carried out a campaign to find and study transelunic objects (TNOS), boulders and ice chunks that circle the sun over the orbit from Neptune in about 30 astronomical units (an astronomical unit is the distance between the earth and the sun). Finding these objects is difficult – they are very small and, as far away from the sun, reflect very cold and very little light.
In recent years, more powerful instruments have emerged that can better look into the Kuiper belt and beyond to identify individual objects. The previously removed object is Farfarout, a rock that is distributed about 400 kilometers and can be found at a distance of 132 astronomical units.
Cheng and his colleagues found in 2017 by201 In archive data collected by the Dark Energy Camera Legacy Survey (decal) and the Canada -France Hawaii Telescope (CFHT). Between 2011 and 2018, Decals and CFHT managed to observe from 2017 from201 A total of 19 times – data that made it possible for the team to characterize the object and its orbit with a high degree of security.
A diagram of the Neptune, Pluto in 2017 and 2017201. (Jiaxuan Li and Sihao Cheng)
2017 by201 was originally discovered at a distance of 90.5 astronomical units, more than twice Pluto's orbital distance of around 40 astronomical units. Its orbit is an extreme ellipse that brings up to 44 astronomical units and emanates up to 1,600 astronomical units – into the inner Oort cloud, the cloud made of stones and ice, which surrounds the solar system to its external borders.
We do not know how this orbit, the completion of which lasts 25,000 years. It is possible that 2017 from201 Had a gravitational interaction with something great that knocked on a literal loop or that the development of its orbit was a multi -stage process.
However, it is clear that it is a completely different orbit than the grouped orbits previously discovered tnos, some of which were diagnostic for diagnostic, invisible planet in the outer solar system.
In fact, the team even led simulations from 2017 from201The orbit in the solar system, both with and without Planet Nine. They found this without a planet nine, 2017 by201 Can have a stable, long -term orbit, as is the case today. With Planet Nine, however, gravitational changes with Neptune Boot 2017 by201 Clean the solar system within 100 million years.
Images from 2017 by201 From the survey data and their trajectory in the sky. (Jiaxuan Li and Sihao Cheng)
It is one of the strongest evidence against the existence of Planet Nine; But it also means that there are many more objects that we have not found in the Kuiper belt and beyond.
“2017 by201 Only one percent of his orbital period spends close enough for us to be demonstrable. The presence of this individual object suggests that there could be about a further hundred other objects with a similar orbit and size. They are just too far away to be recognizable now, “says Cheng.
“Although the progress in telescopes has made it possible for us to explore distant parts of the universe, there is still too much too about our own solar system.”
2017 by201 was officially announced by the international astronomical Union and described in a paper that is available on the Preprint website Arxiv.