Scientists may have discovered the solar system’s 10th planet, more than 3 billion kilometers farther away from the sun than Pluto.
The object — about 10 billion kilometers from Earth — has been given the provisional name of Sedna after the Inuit goddess of the sea.
Sedna was found using the recently launched high power Spitzer Space Telescope.
Initial details indicated Sedna to be made of ice and rock and to be of a smaller size than Pluto, with a diameter of almost 2,000 km.
NASA is set to make an official announcement later Monday.