An artist’s impression of 2018 VG18, nicknamed Farout, the most distant solar system body yet discovered. Image: Roberto Molar Candanosa/Carnegie Institution for Science
Astronomers searching for denizens of the extreme outer solar system, including Planet X, the as-yet-unseen super-Earth thought to be shaping the orbits of Kuiper Belt bodies at enormous distances, have found a 500-kilometre-wide (300-mile-wide) body a record 120 times farther from the Sun than Earth, or roughly 18 billion kilometres (11 billion miles).
Likely taking about 1,000 years to complete one trip around the Sun, the body, appropriately nicknamed “Farout,” is the most distant body yet found in Earth’s solar system, the first at a distance greater than 100 astronomical units, or 15 billion kilometres (9.3 billion miles).
The discovery was made by Carnegie’s Scott S. Sheppard, David Tholen of the University of Hawaii and Chad Trujillo Northern Arizona University using the Japanese Subaru 8-meter telescope atop Mauna Kea in Hawaii on 10 November.
The discovery was confirmed with follow-up observations this month using the Magellan telescope at Carnegie’s Las Campanas Observatory in Chile. Based on its brightness, the researchers concluded it likely is a roughly spherical dwarf planet with a pinkish hue indicating an icy surface.