{{Short description|Rare-type main-belt asteroid}} {{Other uses|Lobachevsky (disambiguation)}} {{Use dmy dates|date=October 2019}} {{Infobox planet | minorplanet = yes | name = 1858 Lobachevskij | background = #D6D6D6 | image = 001858-asteroid shape model (1858) Lobachevskij.png | image_scale = | caption = Lobachevskij modeled from its lightcurve | discovery_ref = <ref name="jpldata" /> | discovered = 18 August 1972 | discoverer = L. Zhuravleva | discovery_site = {{nowrap|Crimean Astrophysical Obs.}} | mpc_name = (1858) Lobachevskij | alt_names = 1972 QL{{·}}1928 SG<br />1936 MH{{·}}1955 VW<br />1957 BM{{·}}1964 YC | named_after = Nikolai Lobachevsky<br />{{small|(Russian mathematician)}}<ref name="springer" /> | mp_category = main-belt{{·}}{{small|(middle)}}<ref name="lcdb" /> | orbit_ref = <ref name="jpldata" /> | epoch = 4 September 2017 (JD 2458000.5) | uncertainty = 0 | observation_arc = 80.42 yr (29,372 days) | aphelion = 2.9086 AU | perihelion = 2.4897 AU | semimajor = 2.6992 AU | eccentricity = 0.0776 | period = 4.43 yr (1,620 days) | mean_anomaly = 98.237° | mean_motion = {{Deg2DMS|0.2223|sup=ms}} / day | inclination = 1.6607° | asc_node = 271.91° | arg_peri = 17.726° | dimensions = {{val|10.769|0.189}}<ref name="Masiero-2011" /><br />{{val|10.919|0.116}} km<ref name="WISE" /><br />13.06 km {{small|(calculated)}}<ref name="lcdb" /> | rotation = {{val|5.409|0.0115}} h {{small|(S)}}<ref name="Waszczak-2015" /><br />{{val|5.413|0.003}} h<ref name="Ditteon-2012" /><br />{{val|5.4141|0.0115}} h {{small|(R)}}<ref name="Waszczak-2015" /><br />{{val|5.435|0.003}} h<ref name="Ditteon-2012" /><br />{{val|7.00|0.01}} h {{small|(dated)}}<ref name="Ditteon-2002b" /> | albedo = 0.18 {{small|(assumed)}}<ref name="lcdb" /><br />{{val|0.3737|0.0590}}<ref name="WISE" /><br />{{val|0.383|0.055}}<ref name="Masiero-2011" /> | spectral_type = SMASS = L<ref name="jpldata" /> | abs_magnitude = 11.5<ref name="WISE" />{{·}}11.9<ref name="jpldata" />{{·}}{{val|11.905|0.002}} {{small|(R)}}<ref name="Waszczak-2015" />{{·}}12.0<ref name="lcdb" />{{·}}{{val|12.368|0.002}} {{small|(S)}}<ref name="Waszczak-2015" /> }}
'''1858 Lobachevskij''' (''prov. designation'': {{mp|1972 QL}}) is a rare-type background asteroid from the central region of the asteroid belt, approximately 13 kilometers in diameter. It was discovered on 18 August 1972, by Soviet astronomer Lyudmila Zhuravleva at the Crimean Astrophysical Observatory in Nauchnyj, on the Crimean peninsula.<ref name="MPC-Lobachevskij" /> The asteroid was named after Russian mathematician Nikolai Lobachevsky.<ref name="springer" />
== Orbit and classification ==
Lobachevskij had already been photographed in precovery images dating back to the 1930s, providing it with a much larger observation arc. It orbits the Sun in the central main-belt at a distance of 2.5–2.9 AU once every 4 years and 5 months (1,620 days). Its orbit has an eccentricity of 0.08 and an inclination of 2° with respect to the ecliptic.<ref name="jpldata" /> First observed as {{mp|1928 SG}} at Heidelberg Observatory in 1928, the asteroid's first used observations was a precovery taken at Palomar Observatory in 1954, extending its observation arc by 18 years prior to its official discovery at Nauchnyj.<ref name="MPC-Lobachevskij" />
== Naming ==
This minor planet was named in honor of mathematician Nikolai Lobachevsky (1792–1856), Russian mathematician and creator of the first comprehensive system of non-Euclidean geometry.<ref name="springer" /> The official {{MoMP|1858|naming citation}} was published by the Minor Planet Center on 1 June 1975 ({{small|M.P.C. 3826}}).<ref name="DoMP-Circular-dates" />
== Physical characteristics ==
Lobachevskij is a strongly reddish and relatively uncommon L-type asteroid in the SMASS classification.<ref name="jpldata" /> It has an absolute magnitude between 11.5 and 12.4.<ref name="lcdb" />
=== Lightcurves ===
In May 2011, photometric observation of Lobachevskij gave a rotation period of 5.413 and 5.435 hours with a brightness amplitude of 0.30 and 0.33 magnitude, respectively ({{small|U=2+/2}}),<ref name="Ditteon-2012" /> superseding a previous period of 7.00 hours ({{small|U=2}}).<ref name="Ditteon-2002b" />
In September 2012, two rotational lightcurves were obtained in the S- and R-band at the Palomar Transient Factory in California. Lightcurve analysis gave a period of 5.409 and 5.4141 hours with an amplitude of 0.26 and 0.22 magnitude, respectively ({{small|U=2/2}}).<ref name="Waszczak-2015" />
=== Occultation ===
Lobachevskij covered a 10.4 mag star—a phenomenon known as occultation—in the constellation Sagittarius in June 2007. It was predicted that the event could be seen in the northeastern United States and southeast Canada. The combined light magnitude of the bodies would drop momentarily—for a maximum of 2.2 seconds.<ref name="asteroidoccultation">{{cite web |url=http://www.asteroidoccultation.com/2007_06/0615_1858_10446_Summary.txt |title=IOTA/IOTA-ES occultation update for (1858) Lobachevskij / TYC 6295-00008-1 event on 2007 Jun 15, 04:51 UT |access-date=2008-03-08 |archive-url=https://archive.today/20070515125850/http://www.asteroidoccultation.com/2007_06/0615_1858_10446_Summary.txt |archive-date=2007-05-15 }}</ref>
=== Diameter and albedo ===
According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Lobachevskij measures between 10.769 and 10.919 kilometers in diameter, and its surface has an albedo between 0.3737 and 0.383, respectively,<ref name="WISE" /><ref name="Masiero-2011" /> while the Collaborative Asteroid Lightcurve Link assumes a lower albedo of 0.18 and calculates a diameter of 12.47 kilometers with an absolute magnitude of 12.0.<ref name="lcdb" />
== References == {{reflist|30em|refs=
<ref name="jpldata">{{cite web |type = 2016-11-23 last obs. |title = JPL Small-Body Database Browser: 1858 Lobachevskij (1972 QL) |url = https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2001858 |publisher = Jet Propulsion Laboratory |access-date = 8 June 2017}}</ref>
<ref name="springer">{{cite book |title = Dictionary of Minor Planet Names – (1858) Lobachevskij |last = Schmadel | first = Lutz D. |publisher = Springer Berlin Heidelberg |page = 149 |date = 2007 |isbn = 978-3-540-00238-3 |doi = 10.1007/978-3-540-29925-7_1859 |chapter = (1858) Lobachevskij }}</ref>
<ref name="MPC-Lobachevskij">{{cite web |title = 1858 Lobachevskij (1972 QL) |work = Minor Planet Center |url = https://www.minorplanetcenter.net/db_search/show_object?object_id=1858 |access-date = 29 March 2017}}</ref>
<ref name="DoMP-Circular-dates">{{cite book |title = Dictionary of Minor Planet Names – Addendum to Fifth Edition (2006–2008) |chapter = Appendix – Publication Dates of the MPCs |last = Schmadel |first=Lutz D. |year = 2009 |publisher = Springer Berlin Heidelberg |page = 221 |isbn = 978-3-642-01964-7 |doi = 10.1007/978-3-642-01965-4|bibcode = 2009dmpn.book.....S }}</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= 29 March 2017}}</ref>
<ref name="lcdb">{{cite LCDB|number = 1858 |access-date = 9 June 2017}}</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="Ditteon-2002b">{{cite journal |author = Ditteon, R. |author2 = Bixby, A. R. |author3 = Sarros, A. M. |author4 = Waters, C. T. |date = December 2002 |title = Rotation Periods and Lightcurves of 1858 Lobachevskij, 2384 Schulhof and (5515) 1989 EL1 |url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2002MPBu...29...69D |journal = The Minor Planet Bulletin |volume = 29 |page = 69 |bibcode = 2002MPBu...29...69D |access-date= 22 August 2016}}</ref>
<ref name="Ditteon-2012">{{cite journal |author = Ditteon, Richard |author2 = Horn, Lauren |author3 = Kamperman, Amy |author4 = Vorjohan, Bradley |author5 = Kirkpatrick, Elaine |date = January 2012 |title = Asteroid Lightcurve Analysis at the Oakley Souther Sky Observatory: 2011 April–May |url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2012MPBu...39...26D |journal = The Minor Planet Bulletin |volume = 39 |issue = 1 |pages = 26–28 |issn = 1052-8091 |bibcode = 2012MPBu...39...26D |access-date= 22 August 2016}}</ref>
<ref name="Waszczak-2015">{{cite journal |display-authors = 6 |author = Waszczak, Adam |author2 = Chang, Chan-Kao |author3 = Ofek, Eran O. |author4 = Laher, Russ |author5 = Masci, Frank |author6 = Levitan, David |author7 = Surace, Jason |author8 = Cheng, Yu-Chi |author9 = Ip, Wing-Huen |author10 = Kinoshita, Daisuke |author11 = Helou, George |author12 = Prince, Thomas A. |author13 = Kulkarni, Shrinivas |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= 22 August 2016}}</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&pg 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|1858}} * {{JPL small body}}
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{{DEFAULTSORT:Lobachevskij}} 001858 Category:Discoveries by Lyudmila Zhuravleva Category:Named minor planets 001858 19720818