Distant World ‘L91’ Discovered In Outer Solar System
Astronomers have reportedly spotted a distant world in the extreme outskirts of the Solar System, far beyond Pluto. The world, called L91 informally, is said to be possibly shifting its way inward from the Oort cloud, an area that is reservoir of icy bodies and comets, to the Kuiper belt. Such a phenomenon of a celestial object shifting like this has never been observed before, as per a report.
According to researchers, L91's discovery reveals more about the worlds that orbit beyond Neptune's gravitational influence. However, it has still not been comprehended how such bodies reached their current orbits. "Every time we find another one of these objects, it adds another piece to the puzzle," planetary scientist Meg Schwamb said.
Incidentally, L91 was detected in 2013 by astronomers associated with the Outer Solar System Origins Survey, using the Canada-France-Hawaii Telescope in Hawaii. The group of researchers has been carrying out detailed surveys of a small part of the sky, with the goal of cataloging and describing the Kuiper-belt objects.
As per the observations by the astronomers, the closest the elliptical orbit of L91 brings it to Earth is around 50 times the Earth-Sun distance, i.e. 50 astronomical units, au, and the world is 1,430 au away at its farthest. The distance implies that the elliptical orbit of L91 is centered farther from the Sun and more stretched out than previously discovered worlds like 2012 VP113 and Sedna.
Astronomers feel that the L91 may have been placed in its distant orbit by gravitational interactions with Neptune in the past. Some researchers feel that the world may have been initially placed as far as 2,000 au from the Sun before it began to make its way back towards the gravitational pull of the star, because it moves around an orbit that is nearly within the Solar System's plane. However, according to another school of thought, the yet undiscovered Planet Nine may be influencing L91's orbit more directly.