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<p>Dwarf planet candidate 2005 QU182, previously identified as of 3.7 absolute magnitude, has been upgraded to 3.1 thanks to recent observations. [Minor Planet Center]</p><p>Absolute magnitude becomes brighter than Varuna (3.6), 2002TC302(3.8), Ixion (3.2), 2002AW197 (3.3). Would be 8th in absolute magnitude behind only Eris, Pluto, Haumea, Makemake, Sedna, Orcus and Quaoar.</p><p>For a given albedo, that corresponds to an increase by 33% in diameter. Depending on albedo, that could make it wider than 1200km. Most probable size range is 600-800km. That would be enough though to secure dwarfplanethood ultimately when IAU gets evidence of its shape. However:</p><p>* large TNOs tend to have higher albedos, that would lead to a lesser increase in diameter</p><p>* changes in surface composition have been observed on Pluto, Eris; could it be that its albedo increases as it goes further from Sun if some components of an atmosphere now freeze (was at perihelion at 37AU in 1970, now at 48AU)?</p>