The origin of the high-inclination Neptune Trojan 2005 TN₅₃

Aims. We explore the formation and evolution of the highly inclined orbit of Neptune Trojan 2005 TN53. Methods. With numerical simulations, we investigated a possible mechanism for the origin of the high-inclination Neptune Trojans as captured into the Trojan-type orbits by an initially eccentric Neptune during its eccentricity damping and rapid inward migration, then migrating to the present locations locked in Neptune's 1: 1 mean motion resonance. Results. Two 2005 TN53-type Trojans out of our 2000 test particles were produced with inclinations above 20 degrees, moving on tadpole orbits librating around Neptune's leading Langrange point.