(842812) 2015 YU9

Main-belt asteroid September 2020 yes (842812) 2015 YU 9 #D6D6D6 16 December 2015 CSS Mount Lemmon Obs. (842812) 2015 YU 9 2015 YB (deleted)jpldata-archivedWY032FF main-belt (inner)Hungaria 4 September 2017 (JD 2458000.5) 5 (32 days) 2.0210 AU 1.7786 AU 1.8998 AU 0.0638 2.62 yr (956 days) 231.75° 0.3764 ms / day 20.031° 236.54° 208.74° 0.35 km (est. at 0.3) 19.228 (842812) 2015 YU 9 is a sub-kilometer Hungaria asteroid from the inner region of the asteroid belt, approximately 350 meters in diameter. It was first observed on 16 December 2015, by the Catalina Sky Survey at Mount Lemmon Observatory in Arizona, United States. Description Orbit 2015 YU 9 is a member of the dynamical Hungaria group, which form the innermost dense concentration of bright asteroids in the Solar System. It orbits the Sun at a distance of 1.8–2.0 AU once every 2 years and 7 months (956 days). Its orbit has an eccentricity of 0.06 and an inclination of 20° with respect to the ecliptic. Discovery Precovery images were taken by Pan-STARRS on 8 December 2015. At the time of discovery the asteroid was 0.8 AU km mi on on from Earth which is close to the Earth minimum orbit intersection distance (MOID). The asteroid came to perihelion (closest approach to the Sun) around 28 December 2015. When the asteroid was first detected and it had an observation arc less than 1 day, the asteroid was suspected of being a Near-Earth asteroid that would make a close approach to Earth on 19 December 2015.jpldata-archived But that orbit solution used an erroneous observation from the Catalina Sky Survey causing an incorrect orbit determination. The asteroid is not a near-Earth object. Diameter and albedo With an absolute magnitude of 19.2, the inner main-belt asteroid is approximately 350 meters in diameter, based on an assumed albedo of 0.3 – a typical compromise value between 0.4 and 0.2, corresponding to the Hungaria asteroids both as family and orbital group. Incorrect media reports Initial mass media reports for the size of the asteroid were incorrectly based on the assumption the asteroid was 0.02 AU from Earth and not 0.8 AU from Earth.August 2017 On 31 December 2015 the asteroid received the provisional designation 2015 YU 9. Notes jpldata-archived https://archive.today/20151217160156/http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2015YB;cad=1 Archived JPL Small Body Data Base, of JPL solution #1 for asteroid 2015 YB on 17 December 2015 with an observation arc of less than a 1 day. This database entry has been deleted since. References 2016-01-09 last obs. JPL Small-Body Database Browser: (2015 YU9) https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=3739059 Jet Propulsion Laboratory 2 August 2017 2015 YU9 Minor Planet Center https://www.minorplanetcenter.net/db_search/show_object?object_id=2015+YU9 2 August 2017 MPEC 2015-Y31 : RETRACTION OF 2015 YB IAU Minor Planet Center 2015-12-19 https://minorplanetcenter.net//mpec/K15/K15Y31.html 9 September 2020 (retraction) Gray Bill Pseudo-MPEC for WY032FF http://www.projectpluto.com/neocp2/mpecs/WY032FF.htm Project Pluto 2015-12-29 https://web.archive.org/web/20151219082232/http://www.projectpluto.com/neocp2/mpecs/WY032FF.htm 19 December 2015 dead dmy-all (NEOCP) Asteroid Size Estimator CNEOS/JPL https://cneos.jpl.nasa.gov/tools/ast_size_est.html 1 August 2017 External links 2015YU9 2015YU9 3739059 842812 (842812) 2015 YU 9 Category:Hungaria asteroids Category:Discoveries by the Catalina Sky Survey 20151216