Astronomers say three space rocks found near Pluto might actually be new dwarf planets. Astronomer Scott Sheppard and his colleagues used the reflectivity of the space rocks to determine their size. However, because the space rocks are so far away, scientists are not sure if they are spherical (which means they would need to be to be named dwarf planets). There are currently five dwarf planets: Pluto, Eris, Ceres, Haumea, and Makemake.

Read more about the three “new Plutos” on National Geographic News.

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