Do you remember why Pluto was relegated from being a planet? Although Pluto is orbiting around the Sun like other planets, and has sufficient gravity to form a nearly round shape, it has not cleared the neighbourhood around its orbit. Hence, Pluto has been classified as a dwarf planet since 2006. However, we do not need to feel sad about it, as Pluto has some other dwarf planet friends in the Solar System, including Ceres, Haumea, Makemake and Eris.

Recently, astronomers have made a new discovery, which may add a dwarf planet companion to Pluto. This potential companion is called "Hygiea". It is the fourth largest celestial object in the asteroid belt. Astronomers discovered it in 1849, but not until the aid of European Southern Observatory (ESO)'s Very Large Telescope (VLT), we are able to observe the surface of Hygiea for the first time in high resolution, and calculate its shape and size. Astronomers found that Hygiea is spherical in shape, which may meet the definition of a dwarf planet. If it is successfully "upgraded", it will become the second dwarf planet in the asteroid belt after Ceres. We are glad that Pluto may make a little new friend!

More information: https://www.eso.org/public/news/eso1918/