Makemake is a classical Kuiper Belt dwarf planet about two-thirds Pluto's size, discovered in 2005 during the same survey that found Eris. Its surface is covered in frozen methane and appears very bright, with no detected atmosphere. In 2016, Hubble discovered MK2, a tiny moon roughly 160 km across orbiting at about 21,000 km — dark compared to Makemake itself, suggesting it may be a captured Kuiper Belt fragment. MK2's orbit allows astronomers to refine Makemake's mass and density. Both bodies orbit far beyond Neptune in the cold, stable region of the classical Kuiper Belt at roughly 45 AU from the Sun.