A Single-chord Stellar Occultation by the Extreme Trans-Neptunian Object (541132) Leleākūhonua
Résumé
A stellar occultation by the extreme large-perihelion trans-Neptunian object (541132) Leleākūhonua (also known by the provisional designation of 2015 TG387) was predicted by the Lucky Star project and observed with the Research and Education Collaborative Occultation Network on 2018 October 20 UT. A single detection and a nearby nondetection provide constraints for the size and albedo. When a circular profile is assumed, the radius is r=110+14−10km,correspondingtoageometricalbedo{p}_{V}={0.21}_{-0.05}^{+0.03}, for an adopted absolute magnitude of HV = 5.6, typical of other objects in dynamically similar orbits. The occultation also provides a high-precision astrometric constraint.