1922 Zulu

Carbonaceous resonant asteroid October 2019 yes 1922 Zulu #D6D6D6 25 April 1949 E. Johnson Johannesburg Obs. (1922) Zulu 1949 HC Zulu (tribe) main-belt(outer)2:1 res 16 February 2017 (JD 2457800.5) 0 67.70 yr (24,727 days) 4.7945 AU 1.6775 AU 3.2360 AU 0.4816 5.82 yr (2,126 days) 187.91° 0.1693 ms / day 35.446° 226.53° 31.395° 0.7153 AU 0.6296 AU 12.41 2.60 km19.30 km (calculated)20.561 0.321 km 18.64 0.01 h18.65 h 0.055 0.0060.057 (assumed)0.16 0.05 C 12.212.27 0.2412.3 1922 Zulu, provisional designation 1949 HC, is a carbonaceous asteroid in a strongly unstable resonance with Jupiter, located in the outermost regions of the asteroid belt, and approximately 20 kilometers in diameter. It was discovered on 25 April 1949, by South African astronomer Ernest Johnson at Union Observatory in Johannesburg, and named for the South African Zulu people. Orbit and classification Zulu is one of few strongly unstable asteroids located near the 2:1 orbital resonance with the gas giant Jupiter, that corresponds to one of the prominent Kirkwood gaps in the asteroid belt. It orbits the Sun at a distance of 1.7–4.8 AU once every 5 years and 10 months (2,126 days). Its orbit has an eccentricity of 0.48 and an inclination of 35° with respect to the ecliptic. The body's observation arc begins with its official discovery observation at Johannesburg, as no precoveries were taken and no prior identifications were made. Zulu was lost shortly after its 1949 discovery, and only rediscovered in 1974 by Richard Eugene McCrosky, Cheng-yuan Shao, and JH Bulger based on a predicted position by C. M. Bardwell of the Cincinnati Observatory. Its orbit is quite highly inclined for asteroids in the asteroid belt, at 35.4 degrees. This may be related to its 2:1 resonance with Jupiter. Physical characteristics In May 2002, a rotational lightcurve of Zulu was obtained from photometric observations by American astronomer Robert Stephens at the Santana Observatory in California. Lightcurve analysis gave a well-defined rotation period of 18.64 hours with a brightness variation of 0.11 magnitude (U=3). One month later, French amateur astronomers René Roy and Laurent Brunetto obtained another lightcurve with a concurring period of 18.65 hours and an amplitude of 0.09 magnitude (U=1). According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Zulu measures 12.41 and 20.561 kilometers in diameter and its surface has an albedo of 0.055 and 0.16. The Collaborative Asteroid Lightcurve Link assumes a standard albedo for a carbonaceous C-type asteroid of 0.057 and calculates a diameter of 19.30 kilometers with an absolute magnitude of 12.3. Naming This minor planet was named after the South African Zulu people, in recognition of the tribesmen who devotedly worked at the Johannesburg Union Observatory. The name also closely relates to 1362 Griqua and 1921 Pala, which also received tribal names and librate in the 2:1 ratio of Jupiter's mean motion as well. The official 1922 naming citation was published by the Minor Planet Center on 20 February 1976 (M.P.C. 3938). See also Griqua group References 2017-01-05 last obs. JPL Small-Body Database Browser: 1922 Zulu (1949 HC) https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2001922 Jet Propulsion Laboratory 31 March 2017 Dictionary of Minor Planet Names – (1922) Zulu Schmadel Lutz D. Springer Berlin Heidelberg 154 2007 978-3-540-00238-3 10.1007/978-3-540-29925-7_1923 (1922) Zulu 1922 Zulu (1949 HC) Minor Planet Center https://www.minorplanetcenter.net/db_search/show_object?object_id=1922 31 March 2017 Dictionary of Minor Planet Names – Addendum to Fifth Edition (2006–2008) 2009 https://archive.org/details/dictionaryminorp2008schm limited Appendix – Publication Dates of the MPCs Schmadel Lutz D. Springer Berlin Heidelberg 221 978-3-642-01964-7 10.1007/978-3-642-01965-4 2009dmpn.book.....S Asteroids and comets rotation curves – (1922) Zulu Behrend Raoul Geneva Observatory http://obswww.unige.ch/~behrend/page4cou.html#001922 31 March 2017 3 August 2003 https://web.archive.org/web/20030803183423/http://obswww.unige.ch/~behrend/page4cou.html#001922 dead F. Roig D. Nesvorný S. Ferraz-Mello September 2002 Asteroids in the 2 : 1 resonance with Jupiter: dynamics and size distribution [ Erratum: 2002MNRAS.336.1391R ] Monthly Notices of the Royal Astronomical Society 335 2 417–431 2002MNRAS.335..417R 10.1046/j.1365-8711.2002.05635.x free International Astronomical Union Circular 2710 – 1949 HC (3rd item) Central Bureau for Astronomical Telegrams Brian G. Marsden 24 October 1974 http://www.cbat.eps.harvard.edu/iauc/02700/02710.html#Item3 31 March 2017 6 Joseph R. Masiero A. K. Mainzer T. Grav J. M. Bauer R. M. Cutri J. Dailey P. R. M. Eisenhardt R. S. McMillan T. B. Spahr M. F. Skrutskie D. Tholen R. G. Walker E. L. Wright E. DeBaun D. Elsbury T. IV Gautier S. Gomillion A. Wilkins November 2011 Main Belt Asteroids with WISE/NEOWISE. I. Preliminary Albedos and Diameters http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2011ApJ...741...68M The Astrophysical Journal 741 2 20 2011ApJ...741...68M 10.1088/0004-637X/741/2/68 1109.4096 31 March 2017 1922 31 March 2017 6 A. Mainzer T. Grav J. Masiero E. Hand J. Bauer D. Tholen R. S. McMillan T. Spahr R. M. Cutri E. Wright J. Watkins W. Mo C. Maleszewski November 2011 NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results The Astrophysical Journal 741 2 25 2011ApJ...741...90M 10.1088/0004-637X/741/2/90 1109.6407 6 C. R. Nugent A. Mainzer J. Masiero J. Bauer R. M. Cutri T. Grav E. Kramer S. Sonnett R. Stevenson E. L. Wright December 2015 NEOWISE Reactivation Mission Year One: Preliminary Asteroid Diameters and Albedos http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2015ApJ...814..117N The Astrophysical Journal 814 2 13 2015ApJ...814..117N 10.1088/0004-637X/814/2/117 1509.02522 31 March 2017 Stephens, R. D. December 2002 Photometry of 769 Tatjana, 818 Kapteyna, 1922 Zulu, and 3687 Dzus http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2002MPBu...29...72S The Minor Planet Bulletin 29 72 2002MPBu...29...72S 31 March 2017 6 Peter Veres Robert Jedicke Alan Fitzsimmons Larry Denneau Mikael Granvik Bryce Bolin Serge Chastel Richard J. Wainscoat William S. Burgett Kenneth C. Chambers Heather Flewelling Nick Kaiser Eugen A. Magnier Jeff S. Morgan Paul A. Price John L. Tonry Christopher Waters November 2015 Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - Preliminary results http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2015Icar..261...34V Icarus 261 34–47 2015Icar..261...34V 10.1016/j.icarus.2015.08.007 1506.00762 31 March 2017 External links Asteroid Lightcurve Database (LCDB), query form (info https://web.archive.org/web/20110721225144/http://www.minorplanet.info/lightcurvedatabase.html 21 July 2011 ) 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 1922 1921 Pala 1922 1923 Osiris 001922 Category:Discoveries by Ernest Leonard Johnson Category:Named minor planets 19490425 01922