Sedna was discovered in 2003 at Palomar Observatory.

It is named after the Inuit sea goddess Sedna.

Sedna is about 1,000 km wide, smaller than Pluto.

It might be a dwarf planet, though not officially confirmed.

Its surface is icy, reddish, and extremely cold.

One orbit around the Sun takes about 11,400 years.

Sedna reflects sunlight from its icy surface.

Its orbit is very long and takes thousands of years to complete.

Sedna is one of the most distant known objects orbiting the Sun.

Its unusual orbit helps scientists study the outer Solar System.