Astronomers have spotted a tiny world with an atmosphere beyond the orbit of Neptune. It should be too small for an atmosphere to be possible.
This hypothetical planet is provisionally known as Planet 9. Computer simulations show it must be a very large planet, consisting of between four and eight times the mass of the Earth and at least ten times the distance of Pluto.
Astronomers have released a catalog of 316 trans-Neptunian objects (TNOs) - minor planets located in the far reaches of the Solar System - detected from the first four years of the Dark Energy Survey.
Using the ALMA, astronomers have revealed extraordinary details about a recently discovered far-flung member of our Solar System, the planetary body 2014 UZ224, more informally known as DeeDee.
Using the Pan-STARRS telescope in Hawaii, astronomers detected a mysterious trans-Neptunian object (TNO) moving backwards around the sun.
