View source for Astronomy:4791 Iphidamas

{{Infobox planet
 | minorplanet     = yes
 | name            = 4791 Iphidamas
 | background      = #C2FFFF
 | image           = 
 | image_size      = 
 | caption         = 
 | discovery_ref   = &thinsp;<ref name="MPC-object" />
 | discoverer      = C. Shoemaker
 | discovery_site  = [[Organization:Palomar Observatory|Palomar Obs.]]
 | discovered      = 14 August 1988
 | mpc_name        = (4791) Iphidamas
 | alt_names       = {{mp|1988 PB|1}}
 | adjective       = Iphidamantian
 | pronounced      = {{IPAc-en|ɪ|ˈ|f|ɪ|d|ə|m|ə|s}}<ref>Noah Webster (1884) ''A Practical Dictionary of the English Language''</ref>
 | named_after     = Iphidamas&thinsp;<ref name="MPC-object" /><br />{{small|(Greek mythology)}}
 | mp_category     = [[Astronomy:Jupiter trojan|Jupiter trojan]]&thinsp;<ref name="MPC-object" /><ref name="jpldata" /><br />{{nowrap|Trojan&thinsp;<ref name="MPC-Jupiter-Trojans" />{{·}}[[Astronomy:Background asteroid|background]]&thinsp;<ref name="AstDys-object" />}}
 | orbit_ref       = &thinsp;<ref name="jpldata" />
 | epoch           = 23 March 2018 ([[Astronomy:Julian day|JD]] 2458200.5)
 | uncertainty     = 0
 | observation_arc = 29.77 [[Astronomy:Julian year|yr]] (10,874 d)
 | aphelion        = 5.3969 [[Astronomy:Astronomical unit|AU]]
 | perihelion      = 4.9230 AU
 | semimajor       = 5.1600 AU
 | eccentricity    = 0.0459
 | period          = 11.72 yr (4,281 d)
 | mean_anomaly    = 91.938[[Degree (angle)|°]]
 | mean_motion     = {{Deg2DMS|0.0841|sup=ms}} / day
 | inclination     = 25.970°
 | asc_node        = 261.46°
 | arg_peri        = 165.77°
 | jupiter_moid    = 0.1002 AU
 | tisserand       = 2.7970
 | mean_diameter   = {{val|49.53|0.66|u=km}}<ref name="Grav-2012" /><br />{{val|57.85|4.0|u=km}}<ref name="SIMPS" /><br />{{val|59.96|1.79|u=km}}<ref name="AKARI" />
 | rotation        = {{val|9.696|0.006|u=h}}<ref name="Stephens-2016j" />{{efn|name=lightcurve-plots-CS3}}
 | albedo          = {{val|0.055|0.004}}<ref name="AKARI" /><br />{{val|0.0579|0.009}}<ref name="SIMPS" /><br />{{val|0.079|0.005}}<ref name="Grav-2012" />
 | spectral_type   = [[Astronomy:C-type asteroid|C]] {{small|(assumed)}}<ref name="lcdb" /><br />B–V {{=}} {{val|0.670|0.060}}<ref name="Chatelain-2016" /><br />V–R {{=}} {{val|0.610|0.040}}<ref name="Chatelain-2016" /><br />V–I {{=}} {{val|1.030|0.049}}<ref name="lcdb" />
 | abs_magnitude   = 9.90<ref name="Grav-2012" /><ref name="SIMPS" /><ref name="AKARI" /><br />10.1<ref name="MPC-object" /><ref name="jpldata" /><ref name="lcdb" />
}}

'''4791 Iphidamas''' {{IPAc-en|ɪ|ˈ|f|ɪ|d|ə|m|ə|s}} is a [[Astronomy:Jupiter trojan|Jupiter trojan]] from the Trojan camp, approximately {{convert|58|km|mi|abbr=off|sigfig=2|sp=us}} in diameter. It was discovered on 14 August 1988, by American astronomer Carolyn Shoemaker at the [[Organization:Palomar Observatory|Palomar Observatory]] in California.<ref name="MPC-object" /> The dark Jovian [[Astronomy:Asteroid|asteroid]] belongs the 100 largest Jupiter trojans and has a [[Rotation period|rotation period]] of 9.7 hours.<ref name="lcdb" /> It was named after the Trojan warrior Iphidamas, from Greek mythology.<ref name="MPC-object" />

== Orbit and classification ==

''Iphidamas'' is a dark [[Astronomy:Jupiter trojan|Jupiter trojan]] in a 1:1 orbital resonance with Jupiter. It is located in the trailering Trojan camp at the Gas Giant's {{L5}} [[Astronomy:Lagrangian point|Lagrangian point]], 60[[Degree (angle)|°]] behind its orbit {{crossreference|(see Trojans in astronomy)}}.<ref name="MPC-Jupiter-Trojans" /> It is also a non-[[Astronomy:Asteroid family|family]] asteroid of the [[Astronomy:Background asteroid|Jovian background population]].<ref name="AstDys-object" />

It orbits the Sun at a distance of 4.9–5.4&nbsp;[[Astronomy:Astronomical unit|AU]] once every 11 years and 9 months (4,281 days; semi-major axis of 5.16&nbsp;AU). Its orbit has an [[Astronomy:Orbital eccentricity|eccentricity]] of 0.05 and an [[Astronomy:Orbital inclination|inclination]] of 26[[Degree (angle)|°]] with respect to the [[Astronomy:Ecliptic|ecliptic]].<ref name="jpldata" /> The body's [[Astronomy:Observation arc|observation arc]] begins with its official discovery observation at Palomar in August 1988.<ref name="MPC-object" />

== Physical characteristics ==

''Iphidamas'' is an assumed, carbonaceous [[Astronomy:C-type asteroid|C-type asteroid]]. It has a high V–I color index of 1.03 ''(see table below)''.<ref name="lcdb" />

=== Rotation period ===

In 2014 and 2015, two rotational [[Astronomy:Lightcurve|lightcurve]]s of ''Iphidamas'' were obtained from [[Astronomy:Photometry|photometric]] observations by Robert Stephens at the Center for Solar System Studies in Landers, California. Analysis of the best-rated lightcurve from December 2015 showed a [[Rotation period|rotation period]] of {{val|9.696|0.006}} hours with a brightness amplitude of 0.31 [[Astronomy:Magnitude|magnitude]] ({{small|U=3}}),<ref name="Stephens-2016j" /><ref name="Stephens-2015f" />{{efn|name=lightcurve-plots-CS3}} superseding a previous period determination by Stefano Mottola at the La Silla Observatory from February 1992, which gave a similar period of 9.57 hours ({{small|U=2+}}).<ref name="lcdb" /><ref name="Mottola-2011" />

=== Diameter and albedo ===

According to the surveys carried out by the [[Astronomy:NEOWISE|NEOWISE]] mission of NASA's [[Astronomy:Wide-field Infrared Survey Explorer|Wide-field Infrared Survey Explorer]], the Infrared Astronomical Satellite [[Astronomy:IRAS|IRAS]], and the Japanese [[Astronomy:Akari (satellite)|Akari satellite]], ''Iphidamas'' measures between 49.528 and 59.96 kilometers in diameter and its surface has an [[Astronomy:Astronomical albedo|albedo]] between 0.055 and 0.079.<ref name="Grav-2012" /><ref name="SIMPS" /><ref name="AKARI" /> The ''Collaborative Asteroid Lightcurve Link'' derives an albedo of 0.0483 and a diameter of 57.74 kilometers based on an [[Astronomy:Absolute magnitude|absolute magnitude]] of 10.1.<ref name="lcdb" />

{{Largest Jupiter trojans}}

== Naming ==

This [[Astronomy:Minor planet|minor planet]] was named from [[Religion:Greek mythology|Greek mythology]] after the Trojan warrior Iphidamas, son of Theano and Antenor, who was the counselor of King Priam. During the Trojan War, he confronted Agamemnon in battle, but his spear bent against Agamemnon's war belt, who then killed Iphidamas with his sword.<ref name="MPC-object" /> The official naming citation was published by the [[Organization:Minor Planet Center|Minor Planet Center]] on 27 June 1991 ({{small|M.P.C. 18465}}).<ref name="MPC-Circulars-Archive" />

== Notes ==
{{notelist|refs=

{{efn|name=lightcurve-plots-CS3|1=Lightcurve plot of (4791) Iphidamas from [http://www.planetarysciences.org/plots/RDS/4791_IPHIDAMAS_2014-11-09.PNG Nov 2014] and [http://www.planetarysciences.org/plots/RDS/4791_IPHIDAMAS_2015-12-18.PNG Dec 2015] by Robert Stephens at the Center for Solar System Studies {{Obscode|U81}}. Quality code is 3-/3 (lightcurve rating at CS3). Summary figures at the [http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=4791%7CIphidamas LCDB] and [http://www.planetarysciences.org/PHP/CS3_Lightcurves.php CS3].}}

}} <!-- end of notelist -->

== References ==
{{reflist|30em|refs=

<ref name="jpldata">{{cite web
  |type       = 2018-05-22 last obs.
  |title      = JPL Small-Body Database Browser: 4791 Iphidamas (1988 PB1)
  |url        = https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2004791
  |publisher  = [[Organization:Jet Propulsion Laboratory|Jet Propulsion Laboratory]]
  |access-date = 20 June 2018}}</ref>

<ref name="MPC-object">{{cite web
  |title      = 4791 Iphidamas (1988 PB1)
  |work       = Minor Planet Center
  |url        = https://www.minorplanetcenter.net/db_search/show_object?object_id=4791
  |access-date = 20 June 2018}}</ref>

<ref name="MPC-Jupiter-Trojans">{{cite web
  |title      = List of Jupiter Trojans
  |work       = Minor Planet Center
  |first3     = V. |last3 = Carruba
  |date       = 1 June 2018
  |url        = https://www.minorplanetcenter.net/iau/lists/JupiterTrojans.html
  |access-date = 20 June 2018}}</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 = 20 June 2018}}</ref>

<ref name="Grav-2012">{{cite journal
  |first1     = T. |last1 = Grav
  |first2     = A. K. |last2 = Mainzer
  |first3     = J. M. |last3 = Bauer
  |first4     = J. R. |last4 = Masiero
  |first5     = C. R. |last5 = Nugent
  |date       = November 2012
  |title      = WISE/NEOWISE Observations of the Jovian Trojan Population: Taxonomy
  |journal    = The Astrophysical Journal
  |volume     = 759
  |issue      = 1
  |page       = 10
  |bibcode    = 2012ApJ...759...49G
  |doi        = 10.1088/0004-637X/759/1/49
  |arxiv      = 1209.1549
  |s2cid = 119101711
 }} ([http://vizier.cfa.harvard.edu/viz-bin/VizieR-6?-source=J/ApJ/759/49/table1&MPC=04791 online catalog])</ref>

<ref name="AstDys-object">{{cite web
  |title      = Asteroid (4791) Iphidamas – Proper Elements
  |publisher  = AstDyS-2, Asteroids – Dynamic Site
  |url        = https://newton.spacedys.com/astdys/index.php?n=4791&pc=1.1.6
  |access-date= 20 June 2018}}</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 – IRAS-A-FPA-3-RDR-IMPS-V6.0
  |pages = IRAS-A-FPA-3-RDR-IMPS-V6.0
 |bibcode    = 2004PDSS...12.....T
  |access-date = 20 June 2018}}</ref>

<ref name="lcdb">{{cite web
  |title      = LCDB Data for (4791) Iphidamas
  |publisher  = Asteroid Lightcurve Database (LCDB)
  |url        = http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=4791%7CIphidamas
  |access-date = 20 June 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= 
  }} ([http://vizier.cfa.harvard.edu/viz-bin/VizieR-5?-source=J/PASJ/63/1117/acua_v1&Num=4791 online], [https://core.ac.uk/download/pdf/43545172.pdf AcuA catalog p. 153])</ref>

<ref name="Mottola-2011">{{cite journal
  |display-authors = 6
  |first1     = Stefano |last1 = Mottola
  |first2     = Mario |last2 = Di Martino
  |first3     = Anders |last3 = Erikson
  |first4     = Maria |last4 = Gonano-Beurer
  |first5     = Albino |last5 = Carbognani
  |first6     = Uri |last6 = Carsenty
  |first7     = Gerhard |last7 = Hahn
  |first8     = Hans-Josef |last8 = Schober
  |first9     = Felix |last9 = Lahulla
  |first10    = Marco |last10 = Delbò
  |first11    = Claes-Ingvar |last11 = Lagerkvist
  |date       = May 2011
  |title      = Rotational Properties of Jupiter Trojans. I. Light Curves of 80 Objects
  |journal    = The Astronomical Journal
  |volume     = 141
  |issue      = 5
  |page       = 32
  |bibcode    = 2011AJ....141..170M
  |doi        = 10.1088/0004-6256/141/5/170|doi-access= free
  }}</ref>

<ref name="Stephens-2015f">{{Cite journal
  |first1     = Robert D. |last1 = Stephens
  |first2     = Daniel R. |last2 = Coley
  |first3     = Linda M. |last3 = French
  |date       = July 2015
  |title      = Dispatches from the Trojan Camp - Jovian Trojan L5 Asteroids Observed from CS3: 2014 October - 2015 January
  |journal    = The Minor Planet Bulletin
  |volume     = 42
  |issue      = 3
  |pages      = 216–224
  |issn       = 1052-8091
  |bibcode    = 2015MPBu...42R.216S}}</ref>

<ref name="Stephens-2016j">{{Cite journal
  |first1     = Robert D. |last1 = Stephens
  |first2     = Daniel R. |last2 = Coley
  |first3     = Linda M. |last3 = French
  |date       = July 2016
  |title      = A Report from the L5 Trojan Camp - Lightcurves of Jovian Trojan Asteroids from the Center for Solar System Studies
  |journal    = The Minor Planet Bulletin
  |volume     = 43
  |issue      = 3
  |pages      = 265–270
  |issn       = 1052-8091
  |bibcode    = 2016MPBu...43..265S}}</ref>

<ref name="Chatelain-2016">{{Cite journal
  |first1     = Joseph P. |last1 = Chatelain
  |first2     = Todd J. |last2 = Henry
  |first3     = Linda M. |last3 = French
  |first4     = Jennifer G. |last4 = Winters
  |first5     = David E. |last5 = Trilling
  |date       = June 2016
  |title      = Photometric colors of the brightest members of the Jupiter L5 Trojan cloud
  |journal    = Icarus
  |volume     = 271
  |pages      = 158–169
  |bibcode    = 2016Icar..271..158C
  |doi        = 10.1016/j.icarus.2016.01.026|doi-access= free
  }}</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
* [https://www.minorplanetcenter.net/iau/lists/NumberedMPs000001.html Discovery Circumstances: Numbered Minor Planets (1)-(5000)] – Minor Planet Center
* [https://sbntools.psi.edu/ferret/SimpleSearch/results.action?targetName=4791+Iphidamas Asteroid 4791 Iphidamas] at the Small Bodies Data Ferret
* {{AstDys|4791}}
* {{JPL small body}}

{{Small Solar System bodies}}

{{DEFAULTSORT:Iphidamas}}
[[Category:Named minor planets]]

{{Sourceattribution|4791 Iphidamas}}