The dwarf planet Makemake (pronounced Mah-kay Mah-kay), in the Kuiper Belt, has been shown by the Hubble Space Telescope to possess a moon.

The arrow in the image below points to the newly discovered satellite, orbiting Makemake, the bright object at the centre of the image.

For more information, visit:
https://www.nasa.gov/feature/goddard/2016/hubble-discovers-moon-orbiting-the-dwarf-planet-makemake