 As of 2008, only five objects in the Solar System (Ceres, Eris, and the KBOs Pluto, Makemake and Haumea) are listed as dwarf planets by the IAU.90482 Orcus, 28978 Ixion and many other Kuiper-belt objects are large enough to be in hydrostatic equilibrium; most of them will probably qualify when more is known about them.The six largest TNOs (Eris, Pluto, Gonggong, Makemake, Haumea and Quaoar) are all known to have satellites, and two have more than one.