Fomalhaut b
The nature of Fomalhaut b is unclear. On one hand, Fomalhaut b could be a planet less than twice Jupiter's mass that is either enshrouded in a spherical cloud of dust from ongoing planetesimal collisions or surrounded by a large circumplanetary ring system, either of which are responsible for scattering the primary star's light and thus making Fomalhaut b visible. Alternatively, it could be a conglomeration of rubble from a recent collision between comet-to-asteroid-sized bodies, and not actually a planet.