It is very likely a dwarf planet. The Spitzer Space Telescope has estimated it to have a diameter of 677±70 km. Light-curve-amplitude analysis shows only small deviations, suggesting that 2004 GV9 could be a spheroid with small albedo spots and hence a dwarf planet.
It has been observed 47 times with precovery images back to 1954.
^ abcJohn Stansberry, Will Grundy, Mike Brown, Dale Cruikshank, John Spencer, David Trilling, Jean-Luc Margot (2007). "Physical Properties of Kuiper Belt and Centaur Objects: Constraints from Spitzer Space Telescope". arXiv:astro-ph/0702538 [astro-ph].
^(Radius of 303.5 km and density of 0.97 = 1.1×1020 kg mass. Radius of 373.5 km and density of 2.3 = 5.0×1020 kg mass)