(523759) 2014 WK₅₀₉ (provisional designation 2014 WK₅₀₉) is a trans-Neptunian object in the scattered disc, located in the outermost regions of the Solar System. It was discovered on 14 September 2010, by Pan-STARRS at Haleakala Observatory on the island of Maui, Hawaii, in the United States.^[1] The object's diameter has been estimated to measure approximately 600 kilometers.^[3][4]

2014 WK₅₀₉ belongs to the scattered disc population. It orbits the Sun at a distance of 40.1–61.6 AU once every 362 years and 6 months (132,399 days; semi-major axis of 50.8 AU). Its orbit has an eccentricity of 0.21 and an inclination of 15° with respect to the ecliptic.^[2] The body's observation arc begins on 14 September 2011 at Haleakala, more than 3 years prior to its official first observation.^[1] Its orbit still has a high uncertainty.^[1][2]

This minor planet was numbered by the Minor Planet Center on 25 September 2018 (M.P.C. 111779).^[5] As of 2018, it has not been named.^[1]

Based on an absolute magnitude of 4.4,^[2] and an assumed albedo of 0.09, the Johnston's archive estimates a mean-diameter of approximately 584 kilometers (363 mi).^[3]

As of 2018, no rotational lightcurve of this object has been obtained from photometric observations. The object's rotation period, pole and shape remain unknown.^[2]