(66146) 1998 TU3

Near-Earth asteroid September 2026 yes (66146) 1998 TU 3 #FFC2E0 Psjae2d11f13 hr.jpg 3D shape model Lightcurve-derived shape model of 1998 TU 3 LINEAR Lincoln Laboratory ETS 13 October 1998 NEOAten 9 June 2026 (JD 2461200.5) 0 1.1685 AU 0.40662 AU 0.78757 AU 0.4837 5.4153° 101.877° 84.9880° 356.822° 1.4102° / d 255.289 d (0.69894 yr) 0.07370 AU 7.285 2.864 1.165 km 0.224 0.216 2.377473 0.000002 h15YORP effect-modelled period 157 1 °15 64 5 °15 -71 2 °15 14.36 (66146) 1998 TU 3 is a moderately large Aten-type near-Earth asteroid. It was discovered on 13 October 1998 by the LINEAR program at Lincoln Laboratory ETS in New Mexico, United States. It is about 2–3 kilometers in diameter and has a rapid rotation, spinning once every 2.38 hours. Its very high axial tilt of 157° means that it rotates in a retrograde direction, opposite in direction to Earth. Its rotation may be affected by the YORP effect. Orbit 1998 TU 3 orbits the Sun on an elliptical orbit at an average distance of 0.79 astronomical units (AU), taking 255 Earth days to complete one orbit. It has an orbital eccentricity of 0.48, causing its distance from the Sun to range from 0.41 AU at perihelion to 1.17 AU at aphelion. Since it is an Earth-crossing asteroid with a semi-major axis of less than one AU, it is classified as an Aten asteroid. It has a relatively low orbital inclination of about 5.4° with respect to the ecliptic plane. Physical characteristics Various estimates of 1998 TU 3's size using data from the Wide-field Infrared Survey Explorer (WISE) range from about 2.7–3.3 km.9 Shape models derived from its observed light curve show that it is relatively rounded and elongated in shape with an equatorial ridge.12 Observations from the Center of Solar System Studies in 2017 detected an apparent mutual event (such as an occultation or eclipse), suggesting the presence of a satellite with an orbital period of 13.6 hours.24 However, later photometric observations support a single object that is likely a rubble pile.15 1998 TU 3 has a rapid rotation period of about 2.38 hours. Long-term observations over a period of 14 years show that its rotation period is gradually lengthening.12 It has a high axial tilt of about 157°, spinning in a retrograde direction.10 Its high axial tilt and lengthening rotation period suggest that its spin is being affected by the YORP effect. However, the YORP effect's intensity drops dramatically with respect to increasing size1998 TU 3 is near the maximum asteroid size where the effect has been demonstratedmaking its effects on the asteroid difficult to confirm.12 Notes References (66146) = 1998 TU3 https://www.minorplanetcenter.net/db_search/show_object?object_id=66146 Minor Planet Center 2026-09-06 (1048 obs) 2026-08-19 last obs. JPL Small-Body Database Lookup: 66146 (1998 TU3) https://ssd.jpl.nasa.gov/tools/sbdb_lookup.html#/?sstr=66146 Jet Propulsion Laboratory 2026-09-06 Warner Brian D. Near-Earth Asteroid Lightcurve Analysis at CS3-Palmer Divide Station: 2017 July Through October January 2018 The Minor Planet Bulletin 45 1 2018MPBu...45...19W Rodríguez Rodríguez Javier Díez Alonso Enrique Iglesias Álvarez Santiago Pérez Fernández Saúl Buendia Roca Alejandro Fernández Díaz Julia Licandro Javier Alarcon Miguel R. Serra-Ricart Miquel Aznar Macías Amadeo de Cos Juez Francisco Javier January 2026 Spin Parameters and Shape Models of Near-Earth Asteroids (4660) Nereus, (21088) Chelyabinsk, (66146) 1998 TU3, and (297418) 2000 SP43 https://iopscience.iop.org/article/10.3847/PSJ/ae2d11 The Planetary Science Journal 7 1 15 10.3847/PSJ/ae2d11 free 2632-3338 2603.14067 NEO Groups NASA/JPL Near-Earth Object Program Office http://neo.jpl.nasa.gov/neo/groups.html https://web.archive.org/web/20020202160655/http://neo.jpl.nasa.gov/neo/groups.html dead 2002-02-02 2012-06-04 External links 66146 66146 66145 1998 TM 66146 66147 1998 TC10 66146 66146 19981013