Astronomers have detected what they believe could be the solar system's tenth planet. It has been called Sedna, after the Inuit ocean goddess.
Images of the planet have been received by the Hubble telescope, as well as by another space telescope, the Spitzer.
Observations of its surface show Sedna to be about 2,000km in diameter, which would make it roughly the same size as Pluto.
It is the first time such a body has been discovered since the discovery of Pluto in 1930.
