title: A thick cloud of Neptune Trojans and their colors.
abstract: The dynamical and physical properties of asteroids offer one of the few constraints on the formation, evolution, and migration of the giant planets. Trojan asteroids share a planet's semimajor axis but lead or follow it by about 60 degrees near the two triangular Lagrangian points of gravitational equilibrium. Here we report the discovery of a high-inclination Neptune Trojan, 2005 TN(53). This discovery demonstrates that the Neptune Trojan population occupies a thick disk, which is indicative of "freeze-in" capture instead of in situ or collisional formation. The Neptune Trojans appear to have a population that is several times larger than the Jupiter Trojans. Our color measurements show that Neptune Trojans have statistically indistinguishable slightly red colors, which suggests that they had a common formation and evolutionary history and are distinct from the classical Kuiper Belt objects.
authors.affiliation: Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road NW, Washington, DC 20015, USA. sheppard@dtm.ciw.edu
authors.forename: Scott S
authors.initials: SS
authors.lastname: Sheppard
authors.forename: Chadwick A
authors.initials: CA
authors.lastname: Trujillo
mesh_terms: D019419:Evolution, Planetary; D018543:Minor Planets; D018541:Neptune