NATIONAL HARBOR, MARYLAND—Astronomers have found the most distant object ever in our solar system, three times farther away than Pluto. The dwarf planet, which has been designated V774104, is between 500 and 1000 kilometers across. It will take another year before scientists pin down its orbit, but it could end up joining an emerging class of extreme solar system objects whose strange orbits point to the hypothetical influence of rogue planets or nearby stars.
“We can’t explain these objects’ orbits from what we know about the solar system,” says Scott Sheppard, an astronomer at the Carnegie Institution for Science in Washington, D.C., who announced the discovery here today at a meeting of the American Astronomical Society. V774104 currently sits 15.4 billion kilometers from the sun, or 103 astronomical units (AU) away. One AU is the distance between Earth and the sun.