A search beyond Neptune uncovers 461 new deep space objects
A six-year search of outer space beyond the orbit of Neptune has uncovered 461 cosmic objects.
The newly discovered objects include four that are more than 230 astronomical units (AU) from the sun. (An astronomical unit is the distance from the Earth to the sun, about 93 million miles). Researchers are hoping that these distance objects might give us some information on Planet Nine, a theoretical, never-observed body that might be hidden in deep space, its gravity affecting the orbits of some of the rock objects at the edge of the solar system.
These new observations have come from the Dark Energy Survey, an effort to map the universe's galactic structure and dark matter that started back in 2013. After six-years of research and observation from the Blanco Telescope located in Cerro Tololo in Chile yielded a total of 817 new objects, 461 of which are now being described for the first time in a paper posted on the preprint service arXiv. ScienceAlert have said that the paper has been submitted to a journal for peer review.
All of the objects in the study are at least 30 AU away, in a part of the universe that is extremely dark and lonely. More than 3,000 trans-Neptunian objects, AKA TNOs, have been discovered in these far out, icy reaches. They include dwarf planets such as Eris and Pluto as well as small Kuiper Belt objects like Arrokoth, a rocky body visited by the New Horizons spacecraft back in 2019. The Kuiper belt is a region of icy objects orbiting between 30 AUs and 50 AUs from the sun.
Out of the newly discovered, 461 objects, a few stand out. Nine of them are known as extreme trans-Neptunian objects, which have orbits that swing out at least 150 AUs from the sun. Four those are extremely extreme, with orbital distances of 230 AUs. At these distances, the objects are barely affected by Neptune's gravity, but their unusual orbits suggest an influence from outside the solar system.
Many researchers are starting to believe that influence might be a currently undiscovered planet, spoken of as Planet Nine.
These newly discovered space objects could potentially help researches prove, or disprove the existence of Planet Nine.
The researchers working on the project have also found four new Neptune Trojans. Trojans are bodies that share the orbits of a planet or a moon. In this case, the objects share Neptune's orbit around the sun.
The researchers also found four new Neptune Trojans. Trojans are bodies that share the orbits of a planet or moon. In this case, the objects share Neptune's orbit around the sun. They also observed the Bernardinelli-Bernstein comet, named after the two lead authors of the paper, University of Pennsylvania cosmologist Gary Bernstein and University of Washington postdoctoral scholar Pedro Bernardinelli. The two researchers were the first to spot the comet in the Dark Energy Survey dataset. The Bernardinelli-Bernstein comet may be up to 100 miles (160 km) wide. It hails from the Oort cloud, another layer of icy objects even more distant than the Kuiper Belt.
At least 155 of the newly discovered objects are what astronomers called "detached." This means that they are far enough from Neptune that the large planet's gravity doesn't affect them much; instead, they're mostly tied to the solar system by the distant pull of the sun. Detached objects, sometimes known as extended scattered disc objects, tend to have huge elliptical orbits.
The findings are exciting, the researchers wrote in their paper, because the Dark Energy Survey wasn't meant as a search for trans-Neptunian objects. Its goals were to characterize the theoretical dark energy that affects the universe's accelerating expansion. Nevertheless, the data from the survey contains 20% of all currently-known TNOs, the researchers wrote, covering an eighth of the sky.
"These will be valuable for further detailed statistical tests of formation models for the trans-Neptunian region," they wrote.