Astronomers have spotted an intriguing cluster of objects in the Kuiper belt, the enormous, donut-shaped region of icy objects beyond the orbit of Neptune.<\/p>\n
As New Scientist reports<\/a>, it\u2019s the second distant structure to have been observed in the far reaches of the solar system. In 2011, researchers discovered a \u201ckernel<\/a>\u201d of well over 100 Kuiper belt objects at 44 astronomical units from the Sun, or 44 times the distance between the Sun and Earth.<\/p>\n This latest \u201cinner kernel\u201d was identified by a team led by Princeton University astrophysicist Amir Siraj, as detailed in a yet-to-be-peer-reviewed paper<\/a>.<\/p>\n The team analyzed the orbital data of 1,650 Kuiper belt objects and trained an algorithm to identify any clustering.<\/p>\n \u201cThe kernel was never found alone \u2014 whenever the algorithm found the kernel, it found another group as well,\u201d Siraj told New Scientist.<\/p>\n The inner kernel, as its name suggests, is only slightly closer to us than the originally identified kernel, at 43 astronomical units from the Sun.<\/p>\n \u201cIt is yet unclear whether the inner kernel is an extension of the kernel or a distinct structure,\u201d the paper reads.<\/p>\n The inner kernel\u2019s objects\u2019 orbits are unusually in line with the solar system\u2019s plane. Many objects found in the vicinity orbit our star at a more eccentric plane, at times tilted by tens of degrees<\/a>.<\/p>\n \u201cThat kind of orbital calmness is a signal of a very old, undisturbed structure \u2014 the kind of structure that can provide clues to the evolution of the solar system, how the giant planets have moved in their orbits, what kind of interstellar environments the solar system has been through, all sorts of things about the early days of the solar system,\u201d Siraj told New Scientist.<\/p>\n The discovery could allow us to better understand how Neptune migrated from the inner solar system to its current location billions of years ago. Experts believe the planet\u2019s outward movement caused Kuiper belt objects to temporarily be caught by Neptune\u2019s gravitational pull, causing them to clump together.<\/p>\n Fortunately, the recently unveiled Vera C. Rubin Observatory in Chile could shed more light on the matter. Given their extreme distance from the Sun, objects in the Kuiper belt receive only a tiny proportion of the star\u2019s light, making them exceedingly difficult to observe. However, the team at the observatory expects to identify about 40,000 objects<\/a> beyond Neptune in the years to come.<\/p>\n \u201cForthcoming observations, including those by the Vera C. Rubin Observatory\u2019s Legacy Survey of Space and Time may provide further evidence for the existence of this [inner kernel] structure, and perhaps resolve the question of whether there are two distinct structures,\u201d Siraj and his colleagues wrote in their paper.<\/p>\n Astronomers have also speculated that the Kuiper belt could be home to much larger objects, the size of dwarf planets, or even an enormous planet several times the size of the Earth, a highly contentious hypothesis<\/a>.<\/p>\n In the meantime, hunting for megastructures in the furthest reaches of our solar system could allow us to better understand how the solar system evolved.<\/p>\n \u201cThe more we learn about the architecture of the Kuiper belt, the more we learn about the solar system\u2019s history,\u201d Siraj told New Scientist.<\/p>\n