1138 Attica

Main-belt asteroid October 2019 yes 1138 Attica #D6D6D6 22 November 1929 K. Reinmuth Heidelberg Obs. (1138) Attica 1929 WF1954 GK ' ae t ᵻ k əAttica Attica Province(province of Greece) main-belt(outer) 16 February 2017 (JD 2457800.5) 0 86.52 yr (31,600 days) 3.3801 AU 2.9104 AU 3.1453 AU 0.0747 5.58 yr (2,037 days) 249.74° 0.1767 ms / day 13.971° 283.50° 107.03° 23.681 0.113 km30 2 km (generic) unknown 0.105 0.018 11.4 1138 Attica, provisional designation 1929 WF, is an asteroid from the outer region of the asteroid belt, approximately 24 kilometers in diameter. It was discovered on 22 November 1929, by German astronomer Karl Reinmuth at Heidelberg Observatory in southwest Germany. It was named after the Attica Province in Greece. Orbit and classification Attica orbits the Sun in the outer main-belt at a distance of 2.9–3.4 AU once every 5 years and 7 months (2,037 days). Its orbit has an eccentricity of 0.07 and an inclination of 14° with respect to the ecliptic. The body's observation arc begins at Heidelberg with its official discovery observation. No precoveries were taken, and no prior identifications were made. Physical characteristics According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Attica measures 23.681 kilometers in diameter and its surface has an albedo of 0.105. Based on a generic magnitude-to-diameter conversion, its diameter is between 13 and 32 kilometer for an absolute magnitude of 11.4 and an assumed albedo in the range of 0.05 to 0.25. Since asteroids in the outer main-belt are typically of carbonaceous rather than stony composition, with averaged standard albedos of 0.057, Atticas diameter can be estimated to measure close to 30 kilometers, as the lower a body's albedo (reflectivity), the larger its diameter at a fixed absolute magnitude (brightness). As of 2017, Atticas spectral type, as well as its rotation period and shape remain unknown. This is rather unusual, as both spectral type and rotation period have been determined for most larger and low-numbered asteroids (also see minor-planet lists from 1 up to 2000). Naming This minor planet is named after the province of Attica in eastern Greece with the capital Athens. Naming citation was first mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 102). References 30em 2016-05-29 last obs. JPL Small-Body Database Browser: 1138 Attica (1929 WF) https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2001138 Jet Propulsion Laboratory 8 February 2017 Dictionary of Minor Planet Names – (1138) Attica Schmadel Lutz D. Springer Berlin Heidelberg 96 2007 978-3-540-00238-3 10.1007/978-3-540-29925-7_1139 (1138) Attica 1138 Attica (1929 WF) Minor Planet Center https://www.minorplanetcenter.net/db_search/show_object?object_id=1138 8 February 2017 Absolute Magnitude (H) NASA/JPL http://neo.jpl.nasa.gov/glossary/h.html https://web.archive.org/web/20010302182040/http://neo.jpl.nasa.gov/glossary/h.html dead 2 March 2001 8 February 2017 6 Joseph R. Masiero T. Grav A. K. Mainzer C. R. Nugent J. M. Bauer R. Stevenson S. Sonnett August 2014 Main-belt Asteroids with WISE/NEOWISE: Near-infrared Albedos http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2014ApJ...791..121M The Astrophysical Journal 791 2 11 2014ApJ...791..121M 10.1088/0004-637X/791/2/121 1406.6645 8 February 2017 1138 8 February 2017 External links Asteroid Lightcurve Database (LCDB), query form (info https://web.archive.org/web/20171216050541/http://www.minorplanet.info/lightcurvedatabase.html 16 December 2017 ) Dictionary of Minor Planet Names, Google books Asteroids and comets rotation curves, CdR https://web.archive.org/web/20160729213840/http://obswww.unige.ch/~behrend/page_cou.html 29 July 2016 – Observatoire de Genève, Raoul Behrend Discovery Circumstances: Numbered Minor Planets (1)-(5000) – Minor Planet Center 1138 1137 Raïssa 1138 1139 Atami 001138 Category:Discoveries by Karl Wilhelm Reinmuth Category:Named minor planets 19291122