{{Short description|Main-belt asteroid}} {{Use dmy dates|date=October 2019}} {{Infobox planet | minorplanet = yes | name = 2228 Soyuz–Apollo | background = #D6D6D6 | image = | image_size = | caption = | discovery_ref = <ref name="jpldata" /> | discovered = 19 July 1977 | discoverer = N. Chernykh | discovery_site = {{nowrap|Crimean Astrophysical Obs.}} | mpc_name = (2228) Soyuz–Apollo | alt_names = 1977 OH{{·}}{{mp|1933 SK|1}}<br />{{mp|1952 DT|1}}{{·}}1963 DD<br />{{mp|1973 YN|3}} | named_after = Apollo–Soyuz {{small|(Test Project)}}<ref name="springer" /> | mp_category = main-belt{{·}}Themis<ref name="lcdb" /> | orbit_ref = <ref name="jpldata" /> | epoch = 4 September 2017 (JD 2458000.5) | uncertainty = 0 | observation_arc = 53.75 yr (19,632 days) | aphelion = 3.7135 AU | perihelion = 2.5605 AU | semimajor = 3.1370 AU | eccentricity = 0.1838 | period = 5.56 yr (2,029 days) | mean_anomaly = 341.70° | mean_motion = {{Deg2DMS|0.1774|sup=ms}} / day | inclination = 1.9888° | asc_node = 140.40° | arg_peri = 285.71° | dimensions = 23.55 km {{small|(calculated)}}<ref name="lcdb" /><br />{{val|26.080|0.295}} km<ref name="WISE" /><ref name="Masiero-2011" /><br />{{val|28.26|0.49}} km<ref name="AKARI" /> | rotation = {{val|5.3846|0.0007}} h<ref name="geneva-obs" /><br />{{val|5.3868|0.0013}} h<ref name="Waszczak-2015" /><br />{{val|5.4|0.05}} h<ref name="geneva-obs" /><br />{{val|6.12}} h<ref name="Almeida-2004" /> | albedo = 0.08 {{small|(assumed)}}<ref name="lcdb" /><br />{{val|0.101|0.004}}<ref name="AKARI" /><br />{{val|0.113|0.020}}<ref name="Masiero-2011" /><br />{{val|0.1134|0.0198}}<ref name="WISE" /> | spectral_type = C<ref name="lcdb" /> | abs_magnitude = 10.9<ref name="WISE" /><ref name="AKARI" />{{·}}{{val|11.21|0.42}}<ref name="Veres-2015" />{{·}}11.5<ref name="jpldata" /><ref name="lcdb" />{{·}}{{val|11.848|0.002}} {{small|(S)}}<ref name="Waszczak-2015" /> }}
'''2228 Soyuz–Apollo''', provisional designation {{mp|1977 OH}}, is a carbonaceous Themistian asteroid from the outer region of the asteroid belt, approximately 26 kilometers in diameter. It was discovered on 19 July 1977, by Soviet–Russian astronomer Nikolai Chernykh at the Crimean Astrophysical Observatory in Nauchnyj on the Crimean peninsula.<ref name="MPC-Soyuz-Apollo" /> It was named after the Apollo–Soyuz Test Project.<ref name="springer" />
== Orbit and classification ==
The dark C-type asteroid is a member of the Themis family, a dynamical family of outer-belt asteroids with nearly coplanar ecliptical orbits. It orbits the Sun in the outer main-belt at a distance of 2.6–3.7 AU once every 5 years and 7 months (2,029 days). Its orbit has an eccentricity of 0.18 and an inclination of 2° with respect to the ecliptic.<ref name="jpldata" />
== Physical characteristics ==
It has a rotation period of 5.4 hours and an albedo of 0.10 and 0.11, as determined by the space-based Akari and WISE missions, respectively,<ref name="AKARI" /><ref name="WISE" /> while the Collaborative Asteroid Lightcurve Link (CALL) assumes a lower albedo of 0.08.<ref name="lcdb" />
== Naming ==
This minor planet was named after the joint Soviet-American space flight, the Apollo–Soyuz Test Project, carried on in 1975. The reversal of the names, "Soyuz–Apollo" rather than "Apollo–Soyuz", was not political, but to prevent confusion with the asteroid 1862 Apollo.<ref name="springer" /> The official naming citation was published by the Minor Planet Center on 1 March 1981 ({{small|M.P.C. 5850}}).<ref name="MPC-Circulars-Archive" />
== References == {{reflist|30em|refs=
<ref name="jpldata">{{cite web |type = 2016-11-23 last obs. |title = JPL Small-Body Database Browser: 2228 Soyuz–Apollo (1977 OH) |url = https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2002228 |publisher = Jet Propulsion Laboratory |access-date = 12 June 2017}}</ref>
<ref name="springer">{{cite book |title = Dictionary of Minor Planet Names – (2228) Soyuz–Apollo |last = Schmadel | first = Lutz D. |publisher = Springer Berlin Heidelberg |page = 181 |date = 2007 |isbn = 978-3-540-00238-3 |doi = 10.1007/978-3-540-29925-7_2229 |chapter = (2228) Soyuz–Apollo }}</ref>
<ref name="MPC-Soyuz-Apollo">{{cite web |title = 2228 Soyuz–Apollo (1977 OH) |work = Minor Planet Center |url = https://www.minorplanetcenter.net/db_search/show_object?object_id=2228 |access-date = 7 December 2016}}</ref>
<ref name="MPC-Circulars-Archive">{{cite web |title = MPC/MPO/MPS Archive |work = Minor Planet Center |url = https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html |access-date = 7 December 2016}}</ref>
<ref name="geneva-obs">{{cite web |title = Asteroids and comets rotation curves – (2228) Soyuz–Apollo |last = Behrend |first = Raoul |publisher = Geneva Observatory |url = https://obswww.unige.ch/~behrend/page4cou.html#002228 |access-date = 7 December 2016}}</ref>
<ref name="lcdb">{{cite LCDB|number = 2228 |access-date = 7 December 2016}}</ref>
<ref name="AKARI">{{cite journal |display-authors = 6 |first1 = Fumihiko |last1 = Usui |first2 = Daisuke |last2 = Kuroda |first3 = Thomas G. |last3 = Müller |first4 = Sunao |last4 = Hasegawa |first5 = Masateru |last5 = Ishiguro |first6 = Takafumi |last6 = Ootsubo |first7 = Daisuke |last7 = Ishihara |first8 = Hirokazu |last8 = Kataza |first9 = Satoshi |last9 = Takita |first10 = Shinki |last10 = Oyabu |first11 = Munetaka |last11 = Ueno |first12 = Hideo |last12 = Matsuhara |first13 = Takashi |last13 = Onaka |date = October 2011 |title = Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey |journal = Publications of the Astronomical Society of Japan |volume = 63 |issue = 5 |pages = 1117–1138 |bibcode = 2011PASJ...63.1117U |doi = 10.1093/pasj/63.5.1117 }} ([http://vizier.cfa.harvard.edu/viz-bin/VizieR-5?-source=J/PASJ/63/1117/acua_v1&Num=2228 online], [https://core.ac.uk/download/pdf/43545172.pdf AcuA catalog p. 153])</ref>
<ref name="WISE">{{cite journal |display-authors = 6 |first1 = A. |last1 = Mainzer |first2 = T. |last2 = Grav |first3 = J. |last3 = Masiero |first4 = E. |last4 = Hand |first5 = J. |last5 = Bauer |first6 = D. |last6 = Tholen |first7 = R. S. |last7 = McMillan |first8 = T. |last8 = Spahr |first9 = R. M. |last9 = Cutri |first10 = E. |last10 = Wright |first11 = J. |last11 = Watkins |first12 = W. |last12 = Mo |first13 = C. |last13 = Maleszewski |date = November 2011 |title = NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results |journal = The Astrophysical Journal |volume = 741 |issue = 2 |page = 25 |bibcode = 2011ApJ...741...90M |doi = 10.1088/0004-637X/741/2/90 |arxiv = 1109.6407|s2cid = 35447010 }}</ref>
<ref name="Almeida-2004">{{Cite journal |first1 = R. |last1 = Almeida |first2 = C. A. |last2 = Angeli |first3 = R. |last3 = Duffard |first4 = D. |last4 = Lazzaro |date = February 2004 |title = Rotation periods for small main-belt asteroids |journal = Astronomy and Astrophysics |volume = 415 |pages = 403–406 |bibcode = 2004A&A...415..403A |doi = 10.1051/0004-6361:20034585 |doi-access= free }}</ref>
<ref name="Waszczak-2015">{{cite journal |display-authors = 6 |first1 = Adam |last1 = Waszczak |first2 = Chan-Kao |last2 = Chang |first3 = Eran O. |last3 = Ofek |first4 = Russ |last4 = Laher |first5 = Frank |last5 = Masci |first6 = David |last6 = Levitan |first7 = Jason |last7 = Surace |first8 = Yu-Chi |last8 = Cheng |first9 = Wing-Huen |last9 = Ip |first10 = Daisuke |last10 = Kinoshita |first11 = George |last11 = Helou |first12 = Thomas A. |last12 = Prince |first13 = Shrinivas |last13 = Kulkarni |date = September 2015 |title = Asteroid Light Curves from the Palomar Transient Factory Survey: Rotation Periods and Phase Functions from Sparse Photometry |url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2015AJ....150...75W |journal = The Astronomical Journal |volume = 150 |issue = 3 |page = 35 |bibcode = 2015AJ....150...75W |doi = 10.1088/0004-6256/150/3/75 |arxiv = 1504.04041 |s2cid = 8342929 |access-date= 7 December 2016}}</ref>
<ref name="Veres-2015">{{cite journal |display-authors = 6 |first1 = Peter |last1 = Veres |first2 = Robert |last2 = Jedicke |first3 = Alan |last3 = Fitzsimmons |first4 = Larry |last4 = Denneau |first5 = Mikael |last5 = Granvik |first6 = Bryce |last6 = Bolin |first7 = Serge |last7 = Chastel |first8 = Richard J. |last8 = Wainscoat |first9 = William S. |last9 = Burgett |first10 = Kenneth C. |last10 = Chambers |first11 = Heather |last11 = Flewelling |first12 = Nick |last12 = Kaiser |first13 = Eugen A. |last13 = Magnier |first14 = Jeff S. |last14 = Morgan |first15 = Paul A. |last15 = Price |first16 = John L. |last16 = Tonry |first17 = Christopher |last17 = Waters |date = November 2015 |title = Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - Preliminary results |url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2015Icar..261...34V |journal = Icarus |volume = 261 |pages = 34–47 |bibcode = 2015Icar..261...34V |doi = 10.1016/j.icarus.2015.08.007 |arxiv = 1506.00762 |s2cid = 53493339 |access-date= 7 December 2016}}</ref>
<ref name="Masiero-2011">{{cite journal |display-authors = 6 |first1 = Joseph R. |last1 = Masiero |first2 = A. K. |last2 = Mainzer |first3 = T. |last3 = Grav |first4 = J. M. |last4 = Bauer |first5 = R. M. |last5 = Cutri |first6 = J. |last6 = Dailey |first7 = P. R. M. |last7 = Eisenhardt |first8 = R. S. |last8 = McMillan |first9 = T. B. |last9 = Spahr |first10 = M. F. |last10 = Skrutskie |first11 = D. |last11 = Tholen |first12 = R. G. |last12 = Walker |first13 = E. L. |last13 = Wright |first14 = E. |last14 = DeBaun |first15 = D. |last15 = Elsbury |first16 = T. IV |last16 = Gautier |first17 = S. |last17 = Gomillion |first18 = A. |last18 = Wilkins |date = November 2011 |title = Main Belt Asteroids with WISE/NEOWISE. I. Preliminary Albedos and Diameters |url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2011ApJ...741...68M |journal = The Astrophysical Journal |volume = 741 |issue = 2 |page = 20 |bibcode = 2011ApJ...741...68M |doi = 10.1088/0004-637X/741/2/68 |arxiv = 1109.4096 |s2cid = 118745497 |access-date= 7 December 2016}}</ref>
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== External links == * [http://www.minorplanet.info/PHP/lcdbsummaryquery.php Asteroid Lightcurve Database (LCDB)], query form ([http://www.minorplanet.info/lightcurvedatabase.html info] {{Webarchive|url=https://web.archive.org/web/20171216050541/http://www.minorplanet.info/lightcurvedatabase.html |date=16 December 2017 }}) * [https://books.google.com/books?id=aeAg1X7afOoC&pg Dictionary of Minor Planet Names], Google books * [https://obswww.unige.ch/~behrend/page_cou.html Asteroids and comets rotation curves, CdR] – Observatoire de Genève, Raoul Behrend * [https://www.minorplanetcenter.net/iau/lists/NumberedMPs000001.html Discovery Circumstances: Numbered Minor Planets (1)-(5000)] – Minor Planet Center * {{AstDys|2228}} * {{JPL small body}}
{{Minor planets navigator |2227 Otto Struve |number=2228 |2229 Mezzarco}} {{Small Solar System bodies}} {{Authority control}}
{{DEFAULTSORT:Soyuz-Apollo}} 002228 Category:Discoveries by Nikolai Chernykh Category:Named minor planets 2228 19770719