Astronomers Have Discovered an Object Beyond the Orbit of Neptune That Could Be Another Dwarf Planet
Astronomers at the Vera Rubin Observatory in Chile have spotted an object beyond Neptune's orbit that could be the sixth dwarf planet discovered to date. The object, currently dubbed 2026 ED138, is likely between 600 and 1500 kilometers (373 to 972 miles) wide, according to astronomers. That means it's probably big enough to have spun itself into a sphere, which is one of the primary requirements to meet the definition of a "dwarf planet." If 2026 ED138 is closer to its minimum estimated size of 600 km, it is roughly one-quarter the diameter of Pluto. If it is closer to the maximum estimate of 1,500 km, it would be about two-thirds the size of Pluto, making it a substantial trans-Neptunian object. The five dwarf planets discovered to date include Pluto, Ceres, Eris, Haumea, and Makemake. ED138 is 46 astronomical units (Earth's distance from the Sun, or 93 million miles per AU), or about…