(516977) 2012 HZ84

Trans-Neptunian object yes (516977) 2012 HZ 84 #C2E0FF 2012 HZ84 by New Horizons.jpg False-color image of 2012 HZ 84 taken byNew Horizons in December 2017 False-color image of 2012 HZ84 taken by New Horizons in December 2017 New Horizons KBO Search Las Campanas Obs. 17 April 2012 (516977) 2012 HZ 84 TNONearScatcubewanodistant 27 April 2019 (JD 2458600.5) 42 5.18 yr (1,893 d) 55.445 AU 37.219 AU 46.332 AU 0.1967 315.38 yr (115,191 d) 321.81 ° 0.0031 ms / day 5.4328° 257.02° 86.064° 74 km (est. at 0.09) 8.9 (516977) 2012 HZ 84 is a small trans-Neptunian object from the Kuiper belt located in the outermost region of the Solar System, approximately 74 km mi off 2 us in diameter. It was discovered on 17 April 2012, by a team of astronomers using one of the Magellan Telescopes in Chile during the New Horizons KBO Search in order to find a potential flyby target for the New Horizons spacecraft. In December 2017, this classical Kuiper belt object was imaged by the spacecraft from afar at a record distance from Earth. Orbit and classification 2012 HZ 84 orbits the Sun at a distance of 37.2–55.4 AU once every 315 years and 5 months (semi-major axis of 46.33 AU). Its orbit has an eccentricity of 0.20 and an inclination of 5.4° with respect to the ecliptic. As a cubewano, also known as a classical Kuiper belt object, 2012 HZ 84 is located in between the resonant plutino and twotino populations and has a low-eccentricity orbit. It belongs to the "stirred" hot population, but only just, since the rather arbitrary threshold to the cold population is typically defined for inclinations lower than 5°. In the object classification of the Deep Ecliptic Survey, however, 2012 HZ 84 has a secured SCATNEAR type, which is a combination of the SCAT and NEAR attributes. It means that the object does not cross the orbit of Neptune but has a higher inclination and eccentricity (SCAT) than the survey's CLASSICAL type objects, and it currently interacts with the dominant ice giant Neptune (NEAR), contrary to the much less gravitationally affected objects of the EXTD type. The body's observation arc begins with its first observation on 17 April 2012, made by astronomers David Osip, Paul Schechter, David Borncamp, Susan Benecchi and Scott Sheppard of the New Horizons KBO Search 268 team using the Magellan II (Clay) telescope at the Las Campanas Observatory, located in the Atacama desert in Chile. Milestone image thumb|left|Trajectory of New Horizons and other nearby Kuiper belt objects When the New Horizons spacecraft imaged 2012 HZ 84 in 2017, it was the farthest from Earth ever captured by a spacecraft. The image was taken by the spacecraft's Long Range Reconnaissance Imager (LORRI) on 5 December 2017 at more than 6.12 billion kilometers (40.9 AU) away from Earth. This record was previously held by the Voyager 1 spacecraft which took the iconic Pale Blue Dot image at 6.06 billion kilometers from Earth in February 1990. In December 2017, New Horizons also imaged the trans-Neptunian object 2012 HE 85, which was first observed by the same team of astronomers the night after they discovered 2012 HZ 84. Both objects held this record for little more than one year, until it was superseded on New Year's Eve 2018/19, when New Horizons made its close flyby of 486958 Arrokoth at a new record distance of 6.4 billion kilometers from Earth. Numbering and naming This minor planet was numbered by the Minor Planet Center on 30 April 2018 and received the number 516977 516977 in the minor planet catalog (M.P.C. 110093). As of 2026, it has not been named. Physical characteristics According to Johnston's Archive, the object measures 74 kilometers in diameter based on an assumed albedo of 0.09 and an absolute magnitude of 8.9. As of 2019, no rotational lightcurve of 2012 HZ 84 has been obtained from photometric observations. The body's rotation period, pole and shape remain unknown. References 30em 2017-06-23 last obs. JPL Small-Body Database Browser: 516977 (2012 HZ84) https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2516977 Jet Propulsion Laboratory 5 January 2019 516977 (2012 HZ84) Minor Planet Center https://www.minorplanetcenter.net/db_search/show_object?object_id=516977 5 January 2019 MPC/MPO/MPS Archive Minor Planet Center https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html 5 January 2019 6 M. W. Buie A. H. Parker D. J. Tholen D. M. Borncamp D. J. Osip P. L. Schechter S. D. Benecchi B. A. McLeod M. Conroy 11 March 2014 2012 HZ84 https://minorplanetcenter.net//mpec/K14/K14E67.html Minor Planet Electronic Circular 2014-E67 2014-E67 (2014) 2014MPEC....E...67B 5 January 2019 List of Known Trans-Neptunian Objects Johnston's Archive 7 October 2018 Johnston Wm. Robert https://www.johnstonsarchive.net/astro/tnoslist.html 5 January 2019 New Horizons Captures Record-Breaking Images in the Kuiper Belt NASA 8 February 2018 https://www.nasa.gov/feature/new-horizons-captures-record-breaking-images-in-the-kuiper-belt 5 January 2019 8 December 2021 https://web.archive.org/web/20211208065245/https://www.nasa.gov/feature/new-horizons-captures-record-breaking-images-in-the-kuiper-belt/ dead Orbit Fit and Astrometric record for 516977 Southwest Research Institute https://www.boulder.swri.edu/~buie/kbo/astrom/516977.html 5 January 2019 Wall Mike The Hunt Is On for Moons Around Ultima Thule 4 January 2019 Space.com https://www.space.com/42894-ultima-thule-moons-new-horizons.html 5 January 2019 External links The Deep Ecliptic Survey Object Classifications List of Transneptunian Objects, Minor Planet Center Discovery Circumstances: Numbered Minor Planets (515001)-(520000) – Minor Planet Center 516977 2516977 January 2019 516977 (516977) 2012 HZ 84 Category:Classical Kuiper belt objects Category:Discoveries by the New Horizons KBO Search 20120417