In the cold, distant reaches of the Solar System, far beyond Pluto, astronomers have just identified what could be a new dwarf planet. It's called 2017 OF201, a rock that appears to be some 700 kilometers (435 miles) across,

Astronomers have announced the discovery of a new dwarf planet in our solar system, named 2017 OF201. Located far beyond Neptune, it orbits the sun every 25,000 years.