View source for Astronomy:30705 Idaios

{{Infobox planet
 | minorplanet     = yes
 | name            = 30705 Idaios
 | background      = #C2FFFF
 | image           = 
 | image_size      = 
 | caption         = 
 | discovery_ref   = &thinsp;<ref name="MPC-object" />
 | discoverer      = [[Biography:Cornelis Johannes van Houten|C. J. van Houten]]<br />[[Biography:Ingrid van Houten-Groeneveld|I. van Houten-G.]]<br />[[Biography:Tom Gehrels|T. Gehrels]]
 | discovery_site  = [[Organization:Palomar Observatory|Palomar Obs.]]
 | discovered      = 16 October 1977
 | mpc_name        = (30705) Idaios
 | alt_names       = 3365 T-3{{·}}{{mp|1989 SD|7}}<br />{{mp|2001 QB|72}}
 | adjective       = Idaian
 | pronounced      = {{IPAc-en|aɪ|ˈ|d|eɪ|ə|s}}<ref>'Idaeus' in Noah Webster (1884) ''A Practical Dictionary of the English Language'', modified for 'ai' spelling</ref>
 | named_after     = Idaios&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 = 63.26 [[Astronomy:Julian year|yr]] (23,106 d)
 | aphelion        = 5.5095 [[Astronomy:Astronomical unit|AU]]
 | perihelion      = 4.8966 AU
 | semimajor       = 5.2030 AU
 | eccentricity    = 0.0589
 | period          = 11.87 yr (4,335 d)
 | mean_anomaly    = 143.04[[Degree (angle)|°]]
 | mean_motion     = {{Deg2DMS|0.0830|sup=ms}} / day
 | inclination     = 19.748°
 | asc_node        = 24.184°
 | arg_peri        = 342.53°
 | jupiter_moid    = 0.0445 AU
 | tisserand       = 2.8790
 | mean_diameter   = {{val|44.55|0.74|ul=km}}<ref name="Grav-2012" />
 | rotation        = {{val|15.736|0.001|ul=h}}<ref name="Stephens-2014c" />{{efn|name=lightcurve-plots-CS3}}
 | albedo          = {{val|0.074|0.010}}<ref name="Grav-2012" />
 | spectral_type   = [[Astronomy:D-type asteroid|D]] {{small|([[Astronomy:Sloan Digital Sky Survey|SDSS]]-MOC)}}<ref name="SDSS-Taxonomy" />
 | abs_magnitude   = 10.2<ref name="Grav-2012" /><br />10.4<ref name="MPC-object" /><ref name="jpldata" />
}}

'''30705 Idaios''' {{IPAc-en|aɪ|ˈ|d|eɪ|ə|s}} is a [[Astronomy:Jupiter trojan|Jupiter trojan]] from the Trojan camp, approximately {{convert|45|km|mi|abbr=off|sigfig=2|sp=us}} in diameter. It was discovered during the third Palomar–Leiden Trojan survey at the [[Organization:Palomar Observatory|Palomar Observatory]] in California in 1977.<ref name="MPC-object" /> The dark [[Astronomy:D-type asteroid|D-type asteroid]] has a [[Rotation period|rotation period]] of 15.7 hours.<ref name="lcdb" /> It was named after the Trojan herald Idaios from Greek mythology.<ref name="MPC-object" />

== Discovery ==
Idaios was discovered on 16 October 1977, by Dutch astronomer couple [[Biography:Ingrid van Houten-Groeneveld|Ingrid]] and Cornelis van Houten at Leiden, on photographic plates taken by Dutch–American astronomer [[Biography:Tom Gehrels|Tom Gehrels]] at the [[Organization:Palomar Observatory|Palomar Observatory]] in California. The body's [[Astronomy:Observation arc|observation arc]] begins with a [[Astronomy:Precovery|precovery]] published by the [[Astronomy:Digitized Sky Survey|Digitized Sky Survey]] and taken at Palomar in February 1955, more than 22 years prior to its official discovery observation.<ref name="MPC-object" />

=== Palomar–Leiden survey ===

== Orbit and classification ==
Idaios is a dark Jovian [[Astronomy:Asteroid|asteroid]] 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)}}. 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 4.9–5.5&nbsp;[[Astronomy:Astronomical unit|AU]] once every 11 years and 10 months (4,335 days; semi-major axis of 5.2&nbsp;AU). Its orbit has an [[Astronomy:Orbital eccentricity|eccentricity]] of 0.06 and an [[Astronomy:Orbital inclination|inclination]] of 20[[Degree (angle)|°]] with respect to the [[Astronomy:Ecliptic|ecliptic]].<ref name="jpldata" />

== Naming ==
This [[Astronomy:Minor planet|minor planet]] was named from [[Religion:Greek mythology|Greek mythology]] after king Priam's herald Idaios, who tells him that Paris and Menelaus want to start a duel. Idaios is the younger son of Dares a priest of the god [[Biology:Hephaestus|Hephaestus]], who helped Idaios to escaped Diomedes as he did not want his priest to lose both his sons.<ref name="MPC-object" /> The official naming citation was published by the [[Organization:Minor Planet Center|Minor Planet Center]] on 18 March 2003 ({{small|M.P.C. 48160}}).<ref name="MPC-Circulars-Archive" />

== Physical characteristics ==
In the [[Astronomy:Sloan Digital Sky Survey|SDSS]]-based taxonomy, Idaios is a dark [[Astronomy:D-type asteroid|D-type asteroid]], the most common type among the Jupiter trojans.<ref name="SDSS-Taxonomy" /><ref name="Ferret" />

=== Rotation period ===
In September 2013, a first rotational [[Astronomy:Lightcurve|lightcurve]] of Idaios was obtained from [[Astronomy:Photometry|photometric]] observations in the R-band by astronomers at the [[Astronomy:Palomar Transient Factory|Palomar Transient Factory]] in California. Lightcurve analysis gave a [[Rotation period|rotation period]] of 15.733 hours with a brightness amplitude of 0.22 [[Astronomy:Magnitude|magnitude]] ({{small|U=2}}).<ref name="lcdb" /><ref name="Waszczak-2015" />

Between 2013 and 2017, three additional period determinations were made by Robert Stephens at the Center for Solar System Studies,<ref name="Stephens-2015f" /><ref name="Stephens-2017f" /> with the best-rated lightcurve from 2014 showing a more refined period {{val|15.736|0.001}} hours and an amplitude of 0.22 magnitude ({{small|U=3}}).<ref name="lcdb" /><ref name="Stephens-2014c" />{{efn|name=lightcurve-plots-CS3}}

=== Diameter and albedo ===
According to the survey carried out by the [[Astronomy:NEOWISE|NEOWISE]] mission of NASA's [[Astronomy:Wide-field Infrared Survey Explorer|Wide-field Infrared Survey Explorer]], Idaios measures 44.546 kilometers in diameter and its surface has an [[Astronomy:Astronomical albedo|albedo]] of 0.074.<ref name="Grav-2012" />

The ''Collaborative Asteroid Lightcurve Link'' assumes a standard albedo for a carbonaceous asteroid of 0.057 and a diameter of 46.30 kilometers based on an [[Astronomy:Absolute magnitude|absolute magnitude]] of 10.4.<ref name="lcdb" />

{{Largest Jupiter trojans}}

== Notes ==
{{notelist|refs=

{{efn|name=lightcurve-plots-CS3|1=Lightcurve plots of (30705) Idaios from [http://www.planetarysciences.org/plots/RDS/30705_IDAIOS_2013-09-04.PNG Sep 2013], [http://www.planetarysciences.org/plots/RDS/30705_IDAIOS_2014-10-13.PNG Oct 2014], and [http://www.planetarysciences.org/plots/RDS/30705_IDAIOS_20170227.PNG Mar 2017], by Robert Stephens at the Center for Solar System Studies {{Obscode|U81}}. Quality code is: 3/3-/3 (lightcurve rating at CS3). Summary figures at the [http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=30705%7CIdaios LCDB] and [http://www.planetarysciences.org/PHP/CS3_Lightcurves.php CS3].}}

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

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

<ref name="jpldata">{{cite web
  |type       = 2018-05-19 last obs.
  |title      = JPL Small-Body Database Browser: 30705 Idaios (3365 T-3)
  |url        = https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2030705
  |publisher  = [[Organization:Jet Propulsion Laboratory|Jet Propulsion Laboratory]]
  |access-date = 25 June 2018}}</ref>

<ref name="MPC-object">{{cite web
  |title      = 30705 Idaios (3365 T-3)
  |work       = Minor Planet Center
  |url        = https://www.minorplanetcenter.net/db_search/show_object?object_id=30705
  |access-date = 25 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 = 25 June 2018}}</ref>

<ref name="MPC-discoverers">{{cite web
  |title      = Minor Planet Discoverers (by number)
  |work       = Minor Planet Center
  |url        = https://www.minorplanetcenter.net/iau/lists/MPDiscsNum.html
  |date       = 31 May 2018
  |access-date = 25 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 = 25 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=30705 online catalog])</ref>

<ref name="AstDys-object">{{cite web
  |title      = Asteroid (30705) Idaios – Proper Elements
  |publisher  = AstDyS-2, Asteroids – Dynamic Site
  |url        = https://newton.spacedys.com/astdys/index.php?n=30705&pc=1.1.6
  |access-date= 25 June 2018}}</ref>

<ref name="SDSS-Taxonomy">{{Cite journal
  |first1     = J. M. |last1 = Carvano
  |first2     = P. H. |last2 = Hasselmann
  |first3     = D. |last3 = Lazzaro
  |first4     = T. |last4 = Mothé-Diniz
  |date       = February 2010
  |title      = SDSS-based taxonomic classification and orbital distribution of main belt asteroids
  |url        = https://sbnarchive.psi.edu/pds3/non_mission/EAR_A_I0035_5_SDSSTAX_V1_1/data/sdsstax_ast_table.tab
  |journal    = Astronomy and Astrophysics
  |volume     = 510
  |page       = 12
  |bibcode    = 2010A&A...510A..43C 
  |doi        = 10.1051/0004-6361/200913322
  |access-date= 30 October 2019|doi-access= free
  }} [https://sbn.psi.edu/pds/resource/sdsstax.html (PDS data set)]</ref>

<ref name="Ferret">{{cite web
  |title      = Asteroid 30705 Idaios
  |work       = Small Bodies Data Ferret
  |url        = https://sbntools.psi.edu/ferret/SimpleSearch/results.action?targetName=30705+Idaios
  |access-date = 25 June 2018}}</ref>

<ref name="lcdb">{{cite web
  |title      = LCDB Data for (30705) Idaios
  |publisher  = Asteroid Lightcurve Database (LCDB)
  |url        = http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=30705%7CIdaios
  |access-date = 25 June 2018}}</ref>

<ref name="Stephens-2017f">{{Cite journal
  |first1     = Robert D. |last1 = Stephens
  |first2     = Daniel R. |last2 = Coley
  |date       = July 2017
  |title      = Lightcurve Analysis of Trojan Asteroids at the Center for Solar System Studies 2017 January - March
  |journal    = The Minor Planet Bulletin
  |volume     = 44
  |issue      = 3
  |pages      = 252–257
  |pmid = 32455404
 |pmc = 7243922
 |issn       = 1052-8091
  |bibcode    = 2017MPBu...44..252S
  }}</ref>

<ref name="Stephens-2014c">{{Cite journal
  |first1     = Robert D. |last1 = Stephens
  |first2     = Linda M. |last2 = French
  |first3     = Chelsea |last3 = Davitt
  |first4     = Daniel R. |last4 = Coley
  |date       = April 2014
  |title      = At the Scaean Gates: Observations Jovian Trojan Asteroids, July- December 2013
  |journal    = The Minor Planet Bulletin
  |volume     = 41
  |issue      = 2
  |pages      = 95–100
  |issn       = 1052-8091
  |bibcode    = 2014MPBu...41...95S
  }}</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="Waszczak-2015">{{cite journal
  |display-authors = 6
  |first1     = Adam |last1 = Waszczak
  |first2     = Chan-Kao |last2 = Chang
  |first3     = Eran O. |last3 = Ofek
  |first4     = Russ |last4 = Laher
  |first5     = Frank |last5 = Masci
  |first6     = David |last6 = Levitan
  |first7     = Jason |last7 = Surace
  |first8     = Yu-Chi |last8 = Cheng
  |first9     = Wing-Huen |last9 = Ip
  |first10    = Daisuke |last10 = Kinoshita
  |first11    = George |last11 = Helou
  |first12    = Thomas A. |last12 = Prince
  |first13    = Shrinivas |last13 = Kulkarni
  |date       = September 2015
  |title      = Asteroid Light Curves from the Palomar Transient Factory Survey: Rotation Periods and Phase Functions from Sparse Photometry
  |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 }}</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/NumberedMPs030001.html Discovery Circumstances: Numbered Minor Planets (30001)-(35000)] – Minor Planet Center
* {{AstDys|30705}}
* {{JPL small body}}

{{Small Solar System bodies}}

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

{{Sourceattribution|30705 Idaios}}