{{Short description|Carbonaceous main-belt asteroid}} {{Use dmy dates|date=March 2018}} {{Infobox planet | minorplanet = yes | name = 1028 Lydina | background = #D6D6D6 | image = | image_size = | caption = | discovery_ref = <ref name="MPC-object" /> | discoverer = V. Albitzkij | discovery_site = Simeiz Obs. | discovered = 6 November 1923 | mpc_name = (1028) Lydina | alt_names = 1923 PG{{·}}A907 JF<br />A914 JA | pronounced = | named_after = {{nowrap|Lydia Il'inichna Albitskaya<ref name="springer" />}}<br />{{small|(discoverer's wife)}} | mp_category = main-belt<ref name="MPC-object" />{{·}}{{small|(outer)}}<ref name="jpldata" /><ref name="lcdb" /><br />background<ref name="Ferret" />{{·}}Cybele{{efn|name=Cybele-group}} | orbit_ref = <ref name="jpldata" /> | epoch = 23 March 2018 (JD 2458200.5) | uncertainty = 0 | observation_arc = 110.80 yr (40,471 d) | aphelion = 3.7695 AU | perihelion = 3.0454 AU | semimajor = 3.4075 AU | eccentricity = 0.1062 | period = 6.29 yr (2,297 d) | mean_anomaly = 346.68° | mean_motion = {{Deg2DMS|0.1567|sup=ms}} / day | inclination = 9.3940° | asc_node = 62.833° | arg_peri = 24.747° | mean_diameter = {{val|71.38|2.2|ul=km}}<ref name="SIMPS" /><br />{{val|81.85|21.71|u=km}}<ref name="Nugent-2015" /><br />{{val|88.526|0.762|u=km}}<ref name="Masiero-2014" /><br />{{val|96.830|1.081|u=km}}<ref name="WISE" /><br />{{val|97.18|1.38|u=km}}<ref name="AKARI" /> | rotation = {{val|11.674|0.002|ul=h}}<ref name="Strabla-2012b" /><br />{{val|11.680|0.005|u=h}}<ref name="Stephens-2012c" /><br />{{val|15.69|u=h}}<ref name="Almeida-2004" /><br />{{val|48|1|u=h}} {{small|(poor)}}<ref name="geneva-obs" /> | albedo = {{val|0.0318|0.0054}}<ref name="WISE" /><br />{{val|0.032|0.001}}<ref name="AKARI" /><br />{{val|0.038|0.006}}<ref name="Masiero-2014" /><br />{{val|0.04|0.05}}<ref name="Nugent-2015" /><br />{{val|0.0586|0.004}}<ref name="SIMPS" /> | spectral_type = Tholen {{=}} C<ref name="jpldata" /><ref name="lcdb" /><br />B–V {{=}} 0.684<ref name="jpldata" /><br />U–B {{=}} 0.276<ref name="jpldata" /> | abs_magnitude = 9.43<ref name="jpldata" /><ref name="lcdb" /><ref name="SIMPS" /><ref name="Nugent-2015" /><ref name="WISE" /><ref name="AKARI" /><br />{{val|10.31|0.76}}<ref name="Veres-2015" /> }}
'''1028 Lydina''', provisional designation {{mp|1923 PG}}, is a carbonaceous background asteroid and member of the Cybele group from the outermost regions of the asteroid belt, approximately {{convert|82|km|mi|abbr=off|sigfig=1|sp=us}} in diameter. It was discovered at the Simeiz Observatory on the Crimean peninsula on 6 November 1923, by Soviet astronomer Vladimir Albitsky, who named it after his wife, Lydia Il'inichna Albitskaya.<ref name="MPC-object" /><ref name="springer" /> The dark C-type asteroid has a rotation period of 11.68 hours.<ref name="lcdb" />
== Orbit and classification ==
''Lydina'' is a non-family asteroid from the main belt's background population when applying the hierarchical clustering method to its proper orbital elements.<ref name="Ferret" /> Based on osculating Keplerian orbital elements, the asteroid is considered a member of the dynamical Cybele group, which are asteroid with low orbital inclinations and eccentricities, and with a semi-major axis between 3.3 and 3.5 AU, near the 4:7 orbital resonance with Jupiter.{{efn|name=Cybele-group}}
It orbits the Sun in the outermost asteroid belt at a distance of 3.0–3.8 AU once every 6 years and 3 months (2,297 days; semi-major axis of 3.41 AU). Its orbit has an eccentricity of 0.11 and an inclination of 9° with respect to the ecliptic.<ref name="jpldata" />
The body's observation arc begins with its first observation as {{mp|A907 JF}} at Heidelberg Observatory in May 1907, more than 16 years prior to its official discovery observation at Simeiz.<ref name="MPC-object" />
== Physical characteristics ==
In the Tholen, ''Lydina'' is a carbonaceous C-type asteroid.<ref name="jpldata" /><ref name="lcdb" />
=== Rotation period ===
In November 2011, a rotational lightcurve of ''Lydina'' was obtained from photometric observations by Robert Stephens at his Santana Observatory {{Obscode|646}} in California. Lightcurve analysis gave a well-defined rotation period of 11.680 hours with a brightness variation of 0.22 magnitude ({{small|U=3}}).<ref name="Stephens-2012c" /> Observations at the Italian Bassano Bresciano Observatory in December 2011 measured a concurring period 11.674 with an amplitude of 0.30 magnitude ({{small|U=3-}}).<ref name="Strabla-2012b" /> A previous observations at the Pico dos Dias Observatory {{Obscode|874}}, Brasil, gave a period of 15.69 hours,<ref name="Almeida-2004" /> which Stephens interpreted as a 4:3-alias period solution of his results.<ref name="Stephens-2012c" /> A provisional lightcurve from March 2007, obtained by French amateur astronomers Pierre Antonini and Jean-Gabriel Bosch (48 hours) is of poor quality ({{small|U=1}}).<ref name="geneva-obs" />
=== Diameter and albedo ===
According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, ''Lydina'' measures between 71.38 and 97.18 kilometers in diameter and its surface has an albedo between 0.0318 and 0.0586.<ref name="SIMPS" /><ref name="Nugent-2015" /><ref name="Masiero-2014" /><ref name="WISE" /><ref name="AKARI" />
The ''Collaborative Asteroid Lightcurve Link'' adopts the results obtained by IRAS, that is, an albedo of 0.0586 and a diameter of 71.38 kilometers based on an absolute magnitude of 9.43.<ref name="lcdb" />
1028 Lydina has been observed to occult 5 stars between 2000 and 2023.
== Naming ==
This minor planet was named after Lydia Il'inichna Albitskaya, wife of the discoverer Vladimir Albitsky (1891–1952).<ref name="springer" /> No accurate naming citation was given for this asteroid in ''The Names of the Minor Planets''. The author of the ''Dictionary of Minor Planets'', Lutz Schmadel, learned about the naming circumstances from Nikolai Chernykh (1931–2004), who was himself a prolific long-time astronomer at Nauchnij, Crimea.<ref name="springer" />
== Notes == {{notelist|refs=
{{efn|name=Cybele-group|1=See [https://books.google.com/books?id=K-0xBsMsursC&dq=Cybele+asteroid&pg=PA96 online excerpt] of Linda T. Elkins-Tanton's book ''Asteroids, meteorites, and comets'' (2011); and orbital criteria in ''Minor planet groups/families'' by [https://www.projectpluto.com/mp_group.htm#cybele projectpluto.com]. Also see comment at {{section link|Asteroid family|Cybele group}}.}}
}} <!-- end of notelist -->
== References == {{reflist|30em|refs=
<ref name="jpldata">{{cite web |type = 2018-02-26 last obs. |title = JPL Small-Body Database Browser: 1028 Lydina (1923 PG) |url = https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2001028 |publisher = Jet Propulsion Laboratory |accessdate = 16 March 2018}}</ref>
<ref name="springer">{{cite book |last = Schmadel | first = Lutz D. |title = Dictionary of Minor Planet Names |publisher = Springer Berlin Heidelberg |page = 88 |date = 2007 |isbn = 978-3-540-00238-3 |doi = 10.1007/978-3-540-29925-7_1029 |chapter = (1028) Lydina }}</ref>
<ref name="MPC-object">{{cite web |title = 1028 Lydina (1923 PG) |work = Minor Planet Center |url = https://www.minorplanetcenter.net/db_search/show_object?object_id=1028 |accessdate = 16 March 2018}}</ref>
<ref name="geneva-obs">{{cite web |title = Asteroids and comets rotation curves – (1028) Lydina |last = Behrend |first = Raoul |publisher = Geneva Observatory |url = http://obswww.unige.ch/~behrend/page3cou.html#001028 |accessdate = 16 March 2018}}</ref>
<ref name="Masiero-2014">{{cite journal |display-authors = 6 |first1 = Joseph R. |last1 = Masiero |first2 = T. |last2 = Grav |first3 = A. K. |last3 = Mainzer |first4 = C. R. |last4 = Nugent |first5 = J. M. |last5 = Bauer |first6 = R. |last6 = Stevenson |first7 = S. |last7 = Sonnett |date = August 2014 |title = Main-belt Asteroids with WISE/NEOWISE: Near-infrared Albedos |journal = The Astrophysical Journal |volume = 791 |issue = 2 |page = 11 |bibcode = 2014ApJ...791..121M |doi = 10.1088/0004-637X/791/2/121 |arxiv = 1406.6645|s2cid = 119293330 }}</ref>
<ref name="Ferret">{{cite web |title = Asteroid 1028 Lydina – Nesvorny HCM Asteroid Families V3.0 |work = Small Bodies Data Ferret |url = https://sbntools.psi.edu/ferret/SimpleSearch/results.action?targetName=1028+Lydina |archive-url = https://web.archive.org/web/20201004033702/https://sbntools.psi.edu/ferret/SimpleSearch/results.action?targetName=1028+Lydina |url-status = dead |archive-date = 4 October 2020 |accessdate = 24 October 2019 }}</ref>
<ref name="lcdb">{{cite LCDB|number = 1028 |accessdate = 16 March 2018}}</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="SIMPS">{{cite journal |first1 = E. F. |last1 = Tedesco |first2 = P. V. |last2 = Noah |first3 = M. |last3 = Noah |first4 = S. D. |last4 = Price |date = October 2004 |title = IRAS Minor Planet Survey V6.0 |url = https://sbnarchive.psi.edu/pds3/iras/IRAS_A_FPA_3_RDR_IMPS_V6_0/data/diamalb.tab |journal = NASA Planetary Data System |volume = 12 |pages = IRAS-A-FPA-3-RDR-IMPS-V6.0 |bibcode = 2004PDSS...12.....T |accessdate = 22 October 2019}}</ref>
<ref name="Nugent-2015">{{cite journal |display-authors = 6 |first1 = C. R. |last1 = Nugent |first2 = A. |last2 = Mainzer |first3 = J. |last3 = Masiero |first4 = J. |last4 = Bauer |first5 = R. M. |last5 = Cutri |first6 = T. |last6 = Grav |first7 = E. |last7 = Kramer |first8 = S. |last8 = Sonnett |first9 = R. |last9 = Stevenson |first10 = E. L. |last10 = Wright |date = December 2015 |title = NEOWISE Reactivation Mission Year One: Preliminary Asteroid Diameters and Albedos |url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2015ApJ...814..117N |journal = The Astrophysical Journal |volume = 814 |issue = 2 |page = 13 |bibcode = 2015ApJ...814..117N |doi = 10.1088/0004-637X/814/2/117 |arxiv = 1509.02522 |s2cid = 9341381 |access-date= 16 March 2018}}</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 |doi-access= free }} ([http://vizier.cfa.harvard.edu/viz-bin/VizieR-5?-source=J/PASJ/63/1117/acua_v1&Num=1028 online], [https://core.ac.uk/download/pdf/43545172.pdf AcuA catalog p. 153])</ref>
<ref name="Stephens-2012c">{{Cite journal |author = Stephens, Robert D. |date = April 2012 |title = Asteroids Observed from GMARS and Santana Observatories: 2011 October- December |url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2012MPBu...39...80S |journal = The Minor Planet Bulletin |volume = 39 |issue = 2 |pages = 80–82 |issn = 1052-8091 |bibcode = 2012MPBu...39...80S |access-date= 16 March 2018}}</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="Strabla-2012b">{{Cite journal |first1 = Luca |last1 = Strabla |first2 = Ulisse |last2 = Quadri |first3 = Roberto |last3 = Girelli |date = July 2012 |title = Lightcurve Analysis for Eight Minor Palnets at Bassano Bresciano Observatory |url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2012MPBu...39..177S |journal = The Minor Planet Bulletin |volume = 39 |issue = 3 |pages = 177–179 |issn = 1052-8091 |bibcode = 2012MPBu...39..177S |access-date= 16 March 2018}}</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= 16 March 2018}}</ref>
}} <!-- end of reflist -->
== 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 Dictionary of Minor Planet Names], Google books * [http://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|1028}} * {{JPL small body}}
{{Minor planets navigator |1027 Aesculapia |number=1028 |1029 La Plata}} {{Small Solar System bodies}} {{Authority control}}
{{DEFAULTSORT:Lydina}} 001028 Lydina Lydina 001028 19231106