{{Short description|Asteroid}} {{Use dmy dates|date=October 2019}} {{Infobox planet | minorplanet = yes | name = 1170 Siva | background = #FA8072 | image = 001170-asteroid shape model (1170) Siva.png | image_scale = | caption = Modelled shape of ''Siva'' from its lightcurve | discovery_ref = <ref name="jpldata" /> | discovered = 29 September 1930 | discoverer = E. Delporte | discovery_site = Uccle Obs. | mpc_name = (1170) Siva | alt_names = 1930 SQ | named_after = Shiva {{small|(Hindu deity)}}<ref name="springer" /> | mp_category = Mars-crosser<ref name="lcdb" /><ref name="MPC-Siva" /><br />Phocaea<ref name="Ferret" /> | orbit_ref = <ref name="jpldata" /> | epoch = 16 February 2017 (JD 2457800.5) | uncertainty = 0 | observation_arc = 85.19 yr (31,116 days) | aphelion = 3.0245 AU | perihelion = 1.6291 AU | semimajor = 2.3268 AU | eccentricity = 0.2998 | period = 3.55 yr (1,296 days) | mean_anomaly = 94.741° | mean_motion = {{Deg2DMS|0.2777|sup=ms}} / day | inclination = 22.184° | asc_node = 0.9218° | arg_peri = 59.391° | moid = 0.7263 AU | mars_moid = 0.3760 AU | dimensions = {{val|7.68|2.18}} km<ref name="Nugent-2016" /><br />{{val|10.37|0.8}} km {{small|(IRAS:2)}}<ref name="SIMPS" /><br />{{val|12.13|0.89}} km<ref name="AKARI" /> | rotation = {{val|3.5}} h<ref name="Szekely-2005" /><br />{{val|4.98}} h{{efn|name=LCDB-CALL-2011}}<br />{{val|5.22|0.01}} h<ref name="geneva-obs" /> | albedo = {{val|0.128|0.020}}<ref name="AKARI" /><br />{{val|0.1751|0.032}} {{small|(IRAS:2)}}<ref name="SIMPS" /><br />{{val|0.40|0.16}}<ref name="Nugent-2016" /> | spectral_type = B–V = 0.864<ref name="jpldata" /><br />U–B = 0.452<ref name="jpldata" /><br />Tholen = S<ref name="jpldata" />{{·}}S<ref name="lcdb" /><ref name="Carry-2016" /> | abs_magnitude = 12.00<ref name="Carry-2016" />{{·}}12.18<ref name="Nugent-2016" />{{·}}12.43<ref name="jpldata" /><ref name="lcdb" /><ref name="SIMPS" /><ref name="AKARI" /> }}
'''1170 Siva''', provisional designation {{mp|1930 SQ}}, is a stony Phocaea asteroid and large Mars-crosser from the innermost regions of the asteroid belt, approximately 10 kilometers in diameter. It was discovered on 29 September 1930, by Belgian astronomer Eugène Delporte at Uccle Observatory in Belgium, and later named after the Hindu deity Shiva.<ref name="springer" /><ref name="MPC-Siva" />
== Orbit and classification ==
''Siva'' is a Mars-crossing asteroid, as it crosses the orbit of Mars at 1.666 AU. It is also a member of the Phocaea family ({{small|701}}).<ref name="Ferret" /> It orbits the Sun at a distance of 1.6–3.0 AU once every 3 years and 7 months (1,296 days). Its orbit has an eccentricity of 0.30 and an inclination of 22° with respect to the ecliptic.<ref name="jpldata" /> ''Siva'' was first observed at the Japanese Kwasan Observatory, 3 days prior to is discovery. The body's observation arc begins at Uccle, two weeks after its official discovery observation.<ref name="MPC-Siva" />
== Naming ==
This minor planet is named after Shiva, a Hindu deity often depicted with a third eye on his forehead and with a snake around his neck.<ref name="springer" /> Naming citation was first mentioned in ''The Names of the Minor Planets'' by Paul Herget in 1955 ({{small|H 109}}).<ref name="springer" />
== Physical characteristics ==
In the Tholen taxonomy, ''Siva'' is a stony S-type asteroid.<ref name="jpldata" />
=== Rotation period ===
Only fragmentary lightcurves of ''Siva'' have been obtained since 2001. They gave a rotation period between 3.5 and 5.22 hours with a small change in brightness of 0.04 to 0.1 magnitude ({{small|U=1/n.a./1}}).<ref name="Szekely-2005" /><ref name="geneva-obs" />{{efn|name=LCDB-CALL-2011}} As of 2017, no secure period has been published.<ref name="lcdb" />
=== Diameter and albedo ===
According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite, and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, ''Siva'' measures between 7.68 and 12.13 kilometers in diameter, and its surface has an albedo between 0.128 and 0.40.<ref name="Nugent-2016" /><ref name="SIMPS" /><ref name="AKARI" /> The ''Collaborative Asteroid Lightcurve Link'' adopts the results obtained by IRAS, that is, an albedo of 0.1751 and a diameter of 10.37 kilometers with an absolute magnitude of 12.43.<ref name="lcdb" /> ''Siva'' belongs to the brightest known Mars-crossers.<ref name="SBDB-query-bright_MCAs" />
== Notes == {{notelist|refs=
{{efn|name=LCDB-CALL-2011|1=CALL (2011) web: rotation period {{val|4.98}} hours with a brightness amplitude of {{val|0.1}} mag. Summary figures at {{URL|1=http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=1170%7CSiva |2=Collaborative Asteroid Lightcurve Link (CALL) for (1170) Siva}}}}
}} <!-- end of notelist -->
== References == {{reflist|30em|refs=
<ref name="jpldata">{{cite web |type = 2016-01-21 last obs. |title = JPL Small-Body Database Browser: 1170 Siva (1930 SQ) |url = https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2001170 |publisher = Jet Propulsion Laboratory |accessdate = 26 January 2017}}</ref>
<ref name="springer">{{cite book |title = Dictionary of Minor Planet Names – (1170) Siva |last = Schmadel | first = Lutz D. |publisher = Springer Berlin Heidelberg |page = 98 |date = 2007 |isbn = 978-3-540-00238-3 |doi = 10.1007/978-3-540-29925-7_1171 |chapter = (1170) Siva }}</ref>
<ref name="MPC-Siva">{{cite web |title = 1170 Siva (1930 SQ) |work = Minor Planet Center |url = https://www.minorplanetcenter.net/db_search/show_object?object_id=1170 |accessdate = 26 January 2017}}</ref>
<ref name="geneva-obs">{{cite web |title = Asteroids and comets rotation curves – (1170) Siva |last = Behrend |first = Raoul |publisher = Geneva Observatory |url = http://obswww.unige.ch/~behrend/page3cou.html#001170 |accessdate = 26 January 2017}}</ref>
<ref name="SBDB-query-bright_MCAs">{{cite web |title = JPL Small-Body Database Search Engine: orbital class (MCA) and H < 12.5 (mag) |publisher = JPL Solar System Dynamics |url = http://ssd.jpl.nasa.gov/sbdb_query.cgi?obj_group=all;obj_kind=all;obj_numbered=all;ast_orbit_class=MCA;OBJ_field=0;ORB_field=0;c1_group=OBJ;c1_item=Ai;c1_op=%3C;c1_value=12.5;table_format=HTML;max_rows=50;format_option=comp;c_fields=AcBhBgBjBiBnBsAi;.cgifields=format_option;.cgifields=obj_kind;.cgifields=obj_group;.cgifields=obj_numbered;.cgifields=ast_orbit_class;.cgifields=table_format;.cgifields=com_orbit_class&query=1&c_sort=AiA}}</ref>
<ref name="Ferret">{{cite web |title = Asteroid 1170 Siva – Nesvorny HCM Asteroid Families V3.0 |work = Small Bodies Data Ferret |url = https://sbntools.psi.edu/ferret/SimpleSearch/results.action?targetName=1170+Siva#Asteroid%201170%20SivaEAR-A-VARGBDET-5-NESVORNYFAM-V3.0 |accessdate = 26 October 2019}}</ref>
<ref name="lcdb">{{cite LCDB|number = 1170 |accessdate = 26 January 2017}}</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="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=1170 online], [https://core.ac.uk/download/pdf/43545172.pdf AcuA catalog p. 153])</ref>
<ref name="Nugent-2016">{{cite journal |display-authors = 6 |first1 = C. R. |last1 = Nugent |first2 = A. |last2 = Mainzer |first3 = J. |last3 = Bauer |first4 = R. M. |last4 = Cutri |first5 = E. A. |last5 = Kramer |first6 = T. |last6 = Grav |first7 = J. |last7 = Masiero |first8 = S. |last8 = Sonnett |first9 = E. L. |last9 = Wright |date = September 2016 |title = NEOWISE Reactivation Mission Year Two: Asteroid Diameters and Albedos |journal = The Astronomical Journal |volume = 152 |issue = 3 |page = 12 |bibcode = 2016AJ....152...63N |doi = 10.3847/0004-6256/152/3/63 |arxiv = 1606.08923 |doi-access = free }}</ref>
<ref name="Szekely-2005">{{cite journal |display-authors = 6 |first1 = P. |last1 = Székely |first2 = L. L. |last2 = Kiss |first3 = Gy. M. |last3 = Szabó |first4 = K. |last4 = Sárneczky |first5 = B. |last5 = Csák |first6 = M. |last6 = Váradi |first7 = Sz. |last7 = Mészáros |date = August 2005 |title = CCD photometry of 23 minor planets |url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2005P&SS...53..925S |journal = Planetary and Space Science |volume = 53 |issue = 9 |pages = 925–936 |bibcode = 2005P&SS...53..925S |doi = 10.1016/j.pss.2005.04.006 |arxiv = astro-ph/0504462 |s2cid = 119361591 |access-date= 26 January 2017}}</ref>
<ref name="Carry-2016">{{Cite journal |first1 = B. |last1 = Carry |first2 = E. |last2 = Solano |first3 = S. |last3 = Eggl |first4 = F. E. |last4 = DeMeo |date = April 2016 |title = Spectral properties of near-Earth and Mars-crossing asteroids using Sloan photometry |url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2016Icar..268..340C |journal = Icarus |volume = 268 |pages = 340–354 |bibcode = 2016Icar..268..340C |doi = 10.1016/j.icarus.2015.12.047 |access-date= 26 January 2017|arxiv = 1601.02087 |s2cid = 119258489 }}</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|1170}} * {{JPL small body}}
{{Minor planets navigator |1169 Alwine |number=1170 |1171 Rusthawelia}} {{Small Solar System bodies}} {{Authority control}}
{{DEFAULTSORT:Siva}} 001170 001170 Category:Discoveries by Eugène Joseph Delporte Category:Named minor planets 001170 19300929