It was discovered on 20 August 2004 by the Siding Spring Survey at an apparent magnitude of 16.5 using the 0.5-metre (20 in) Uppsala Southern Schmidt Telescope.
Unlike many other members of this dynamical group, 2004 QY2 is not a Mars-crosser, as its aphelion is too small to cross the orbit of the Red Planet at 1.66 AU.
[3] With an absolute magnitude of 14.7, 2004 QY2 is one of the brightest potentially hazardous asteroids ever discovered (see PHA-list).
[3] Due to its originally estimated size of 5.5 kilometers, 2004 QY2 was one of the largest objects to appear on the Sentry Risk Table.
The body's rotation period, shape and spin axis remain unknown.