{{Short description|Metallic main-belt asteroid}} {{Use dmy dates|date=October 2019}} {{Infobox planet | minorplanet = yes | name = 1181 Lilith | background = #D6D6D6 | symbol = 24px (astrological) | image = | caption = | discovery_ref = <ref name="MPC-object" /> | discovered = 11 February 1927 | discoverer = B. Jekhovsky | discovery_site = Algiers Obs. | mpc_name = (1181) Lilith | alt_names = 1927 CQ{{·}}1925 QF<br />1943 WC{{·}}1953 CA<br />1964 PG{{·}}A914 BA | named_after = Lili Boulanger<br />{{small|(French composer)}}<ref name="springer" /> | mp_category = {{nowrap|main-belt{{·}}{{small|(middle)}}<ref name="lcdb" />}}<br />background<ref name="AstDys-object" /><ref name="Ferret" /><ref name="Zappala-family" /> | orbit_ref = <ref name="jpldata" /> | epoch = 31 May 2020 (JD 2459000.5) | uncertainty = 0 | observation_arc = 89.50 yr (32,689 d) | aphelion = 3.1851 AU | perihelion = 2.1457 AU | semimajor = 2.6654 AU | eccentricity = 0.1950 | period = 4.35 yr (1,589 d) | mean_anomaly = 219.56° | mean_motion = {{Deg2DMS|0.2265|sup=ms}} / day | inclination = 5.6012° | asc_node = 260.70° | arg_peri = 156.05° | mean_diameter = {{val|20.492|0.276|ul=km}}<ref name="Mainzer-2016" /><ref name="Masiero-2014" /> | rotation = {{val|15.04|0.01|ul=h}}<ref name="Ferrero-2014c" /> | albedo = {{val|0.106|0.011}}<ref name="Masiero-2014" /> | spectral_type = SMASS {{=}} X<ref name="jpldata" /><ref name="Ferret" /> | abs_magnitude = 11.3<ref name="MPC-object" /><ref name="jpldata" /> }}
'''1181 Lilith''' (''prov. designation:'' {{mp|1927 CQ}}) is a metallic asteroid from the middle region of the asteroid belt, approximately {{convert|23|km|mi|abbr=off|sigfig=2|sp=us}} in diameter. It was discovered on 11 February 1927, by Russian–French astronomer Benjamin Jekhowsky at Algiers Observatory in Algeria, Northern Africa, and named after French composer Lili Boulanger.<ref name="springer" /><ref name="MPC-object" />
== Classification and orbit ==
''Lilith'' is a non-family asteroid of the main belt's background population when applying the hierarchical clustering method to its proper orbital elements.<ref name="AstDys-object" /><ref name="Ferret" /><ref name="Zappala-family" /> It orbits the Sun in the middle asteroid belt at a distance of 2.1–3.2 AU once every 4 years and 4 months (1,587 days). Its orbit has an eccentricity of 0.20 and an inclination of 6° with respect to the ecliptic.<ref name="jpldata" /> First observed as {{mp|A914 BA}} at Simeiz Observatory in 1914, ''Lilith''{{'}}s observation arc begins 7 years after its official discovery observation, with its first used observation made at Konkoly Observatory in 1934.<ref name="MPC-object" />
== Naming ==
This minor planet was named by Jekhowsky for Marie Juliette Boulanger (1893–1918), nicknamed Lili. She was the younger sister of Nadia Boulanger and daughter of Ernest Boulanger.<ref name="springer" />
== Physical characteristics ==
''Lilith'' is an X-type asteroid in the Bus–Binzel SMASS taxonomy. It has also been classified as a P-type asteroid by NASA's space-based Wide-field Infrared Survey Explorer (WISE).<ref name="lcdb" />
=== Rotation period ===
In February 2014, a rotational lightcurve of ''Lilith'' was obtained by Italian astronomer Andrea Ferrero at the Bigmuskie Observatory {{Obscode|B88}} in Mombercelli, Italy. The photometric observations rendered a period of {{val|15.04|0.01}} hours with a brightness amplitude of 0.11 in magnitude ({{small|U=2}}).<ref name="Ferrero-2014c" />
=== Diameter and albedo ===
According to NASA's WISE telescope with its subsequent NEOWISE mission, ''Lilith'' measures ({{val|20.492|0.276}}) kilometers in diameter and its surface has an albedo of ({{val|0.106|0.011}}),<ref name="Mainzer-2016" /><ref name="Masiero-2014" /> while the ''Collaborative Asteroid Lightcurve Link'' assumes an albedo of 0.10, and calculates a diameter of 24.2 kilometers with an absolute magnitude of 11.2.<ref name="jpldata" /> The WISE team also published an alternative mean diameter ({{val|22.133|0.254|u=km}}) and an albedo of ({{val|0.116|0.022}}).<ref name="Ferret" />
== References == {{reflist|30em|refs=
<ref name="jpldata">{{cite web |type = 2020-06-17 last obs. |title = JPL Small-Body Database Browser: 1181 Lilith (1927 CQ) |url = https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2001181 |publisher = Jet Propulsion Laboratory |accessdate = 21 July 2020}}</ref>
<ref name="springer">{{cite book |title = Dictionary of Minor Planet Names |last = Schmadel | first = Lutz D. |publisher = Springer Berlin Heidelberg |chapter = (1181) Lilith |page = 99 |date = 2007 |isbn = 978-3-540-00238-3 |doi = 10.1007/978-3-540-29925-7_1182}}</ref>
<ref name="MPC-object">{{cite web |title = 1181 Lilith (1927 CQ) |work = Minor Planet Center |url = https://www.minorplanetcenter.net/db_search/show_object?object_id=1181 |accessdate = 21 July 2020}}</ref>
<ref name="lcdb">{{cite LCDB|number = 1181 |accessdate = 25 May 2016}}</ref>
<ref name="Ferrero-2014c">{{Cite journal |author = Ferrero, Andrea |date = July 2014 |title = Period Determination of Six Main Belt Asteroids |url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2014MPBu...41..184F |journal = The Minor Planet Bulletin |volume = 41 |issue = 3 |pages = 184–185 |issn = 1052-8091 |bibcode = 2014MPBu...41..184F |access-date= 25 May 2016}}</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 |url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2014ApJ...791..121M |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 |access-date= 9 December 2016}}</ref>
<ref name="Mainzer-2016">{{cite journal |display-authors = 6 |first1 = A. K. |last1 = Mainzer |first2 = J. M. |last2 = Bauer |first3 = R. M. |last3 = Cutri |first4 = T. |last4 = Grav |first5 = E. A. |last5 = Kramer |first6 = J. R. |last6 = Masiero |first7 = C. R. |last7 = Nugent |first8 = S. M. |last8 = Sonnett |first9 = R. A. |last9 = Stevenson |first10 = E. L. |last10 = Wright |date = June 2016 |title = NEOWISE Diameters and Albedos V1.0 |url = https://sbnarchive.psi.edu/pds3/non_mission/EAR_A_COMPIL_5_NEOWISEDIAM_V1_0/data/neowise_mainbelt.tab |journal = NASA Planetary Data System |bibcode = 2016PDSS..247.....M |access-date= 21 July 2020}}</ref>
<ref name="Ferret">{{cite web |title = Asteroid 1181 Lilith – Nesvorny HCM Asteroid Families V3.0 |work = Small Bodies Data Ferret |url = https://sbntools.psi.edu/ferret/SimpleSearch/results.action?targetName=1181+Lilith |accessdate = 21 July 2020}}</ref>
<ref name="AstDys-object">{{cite web |title = Asteroid 1181 Lilith – Proper Elements |publisher = AstDyS-2, Asteroids – Dynamic Site |url = https://newton.spacedys.com/astdys/index.php?pc=1.1.6&n=1181 |access-date= 21 July 2020}}</ref>
<ref name="Zappala-family">{{cite journal |last1 = Zappalà |first1 = V. |last2 = Bendjoya |first2 = Ph. |last3 = Cellino |first3 = A. |last4 = Farinella |first4 = P. |last5 = Froeschle |first5 = C. |date = 1997 |title = Asteroid Dynamical Families |url = https://sbnarchive.psi.edu/pds3/non_mission/EAR_A_5_DDR_FAMILY_V4_1/data/family.tab |journal = NASA Planetary Data System |pages = EAR-A-5-DDR-FAMILY-V4.1 |accessdate = 21 July 2020}} ([https://sbn.psi.edu/pds/resource/family.html PDS main page])</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|1181}} * {{JPL small body}}
{{Minor planets navigator|1180 Rita|number=1181|1182 Ilona}} {{Small Solar System bodies}} {{Authority control}}
{{DEFAULTSORT:Lilith}} 001181 Category:Discoveries by Benjamin Jekhowsky Category:Named minor planets 001181 19270211