2456 Palamedes
{{Use dmy dates|date=February 2019}}
{{Infobox planet
| minorplanet = yes
| name = 2456 Palamedes
| background = #C2FFFF
| image =
| image_size =
| caption =
| discoverer = {{nowrap|Purple Mountain Obs.}}
| discovery_site = Purple Mountain Obs.
| discovered = 30 January 1966
| mpc_name = (2456) Palamedes
| alt_names = {{mp|1966 BA|1}}{{·}}1973 TJ
{{mp|1977 AK|1}}{{·}}1979 EF
| adjective = Palamedian
| pronounced = {{IPAc-en|p|æ|l|ə|ˈ|m|iː|d|iː|z}}Noah Webster (1884) A Practical Dictionary of the English Language
| named_after = Palamedes
{{small|(Greek mythology)}}
| mp_category = Jupiter trojan
Greek
| epoch = 27 April 2019 (JD 2458600.5)
| uncertainty = 0
| observation_arc = 65.59 yr (23,955 d)
| aphelion = 5.5103 AU
| perihelion = 4.7498 AU
| semimajor = 5.1301 AU
| eccentricity = 0.0741
| period = 11.62 yr (4,244 d)
| mean_anomaly = {{val|260.35|ul=°}}
| mean_motion = {{Deg2DMS|0.0848|sup=ms}} / day
| inclination = 13.912°
| asc_node = 327.36°
| arg_peri = 94.744°
| jupiter_moid = 0.1197 AU
| tisserand = 2.9370
| mean_diameter = {{val|65.92|0.51|ul=km}}
{{val|91.66|3.1|u=km}}
{{val|99.60|4.11|u=km}}
| rotation = {{val|7.24|0.01|ul=h}}
| albedo = {{val|0.026|0.002}}
{{val|0.0304|0.002}}
{{val|0.071|0.010}}
| spectral_type = C {{small|(assumed)}}
V–I {{=}} {{val|0.920|0.024}}
}}
2456 Palamedes {{IPAc-en|p|æ|l|ə|ˈ|m|iː|d|iː|z}} is a large Jupiter trojan from the Greek camp, approximately {{convert|90|km|mi|abbr=off|sigfig=2|sp=us}} in diameter. It was discovered on 30 January 1966, by astronomers at the Purple Mountain Observatory in Nanking, China. The assumed C-type asteroid has a rotation period of 7.24 hours and belongs to the 50 largest Jupiter trojans. It was named after Palamedes from Greek mythology.
Orbit and classification
Palamedes is a dark Jovian asteroid orbiting in the leading Greek camp at Jupiter's {{L4}} Lagrangian point, 60° ahead of the Gas Giant's orbit in a 1:1 resonance (see Trojans in astronomy). It is also a non-family asteroid in the Jovian background population.
It orbits the Sun at a distance of 4.7–5.5 AU once every 11 years and 7 months (4,244 days; semi-major axis of 5.13 AU). Its orbit has an eccentricity of 0.07 and an inclination of 14° with respect to the ecliptic. The body's observation arc begins with a precovery taken at Palomar Observatory in February 1953, nearly 13 years prior to its official discovery observation at Nanking.
Naming
This minor planet was named from Greek mythology after Palamedes, the most intelligent of all the Greek commanders of the Trojan War. The official naming citation was published by the Minor Planet Center on 28 January 1983 ({{small|M.P.C. 7618}}).
Physical characteristics
Palamedes is an assumed carbonaceous C-type asteroid. It has an average V–I color index of {{val|0.920|0.024}}, typically associated with D-type asteroid (also see table below).
= Rotation period =
In August 1995, a rotational lightcurve of Palamedes was obtained from photometric observations by Stefano Mottola and Hans-Josef Schober using the now decommissioned Bochum 0.61-metre Telescope at ESO's La Silla Observatory in Chile. Lightcurve analysis gave a rotation period of {{val|7.258|0.004}} hours and a brightness variation of 0.05 magnitude ({{small|U=2-}}).
A more refined period of {{val|7.24|0.01}} hours with an amplitude of 0.27 magnitude was obtained by Robert Stephens at the Goat Mountain Astronomical Research Station {{Obscode|G79}} in October 2009 ({{small|U=3}}).
= Diameter and albedo =
According to the surveys carried out by the Japanese Akari satellite, the Infrared Astronomical Satellite IRAS, and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Palamedes measures between 65.92 and 99.60 kilometers in diameter and its surface has an albedo between 0.026 and 0.071. The Collaborative Asteroid Lightcurve Link derives an albedo of 0.0399 and a diameter of 91.83 kilometers based on an absolute magnitude of 9.3.
{{Largest Jupiter trojans}}
References
{{reflist|30em|refs=
|type = 2018-09-17 last obs.
|title = JPL Small-Body Database Browser: 2456 Palamedes (1966 BA1)
|url = https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2002456
|archive-url = https://web.archive.org/web/20200918020950/https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2002456
|url-status = dead
|archive-date = 18 September 2020
|publisher = Jet Propulsion Laboratory
|access-date = 12 February 2019}}
|last = Schmadel | first = Lutz D.
|title = Dictionary of Minor Planet Names |publisher = Springer Berlin Heidelberg
|chapter = (2456) Palamedes
|page = 200
|date = 2007
|isbn = 978-3-540-29925-7
|doi = 10.1007/978-3-540-29925-7_2457}}
|title = 2456 Palamedes (1966 BA1)
|work = Minor Planet Center
|url = https://www.minorplanetcenter.net/db_search/show_object?object_id=2456
|access-date = 12 February 2019}}
|title = List of Jupiter Trojans
|work = Minor Planet Center
|date = 28 October 2018
|url = https://www.minorplanetcenter.net/iau/lists/JupiterTrojans.html
|access-date = 12 February 2019}}
|title = MPC/MPO/MPS Archive
|work = Minor Planet Center
|url = https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html
|access-date = 12 February 2019}}
|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=02456 online catalog])
|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
|volume = 12
|pages = IRAS-A-FPA-3-RDR-IMPS-V6.0
|bibcode = 2004PDSS...12.....T
|access-date = 15 June 2018}}
|title = Asteroid (2456) Palamedes – Proper elements
|publisher = AstDyS-2, Asteroids – Dynamic Site
|url = https://newton.spacedys.com/astdys/index.php?n=2456&pc=1.1.6
|access-date = 6 June 2018}}
|title = Asteroid 2456 Palamedes
|work = Small Bodies Data Ferret
|url = https://sbntools.psi.edu/ferret/SimpleSearch/results.action?targetName=2456+Palamedes
|access-date = 6 June 2018}}
|title = LCDB Data for (2456) Palamedes
|publisher = Asteroid Lightcurve Database (LCDB)
|url = http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=2456%7CPalamedes
|access-date = 12 February 2019}}
|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=2456 online], [https://core.ac.uk/download/pdf/43545172.pdf AcuA catalog p. 153])
|author = Stephens, Robert D.
|date = April 2010
|title = Trojan Asteroids Observed from GMARS and Santana Observatories: 2009 October - December
|url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2010MPBu...37...47S
|journal = The Minor Planet Bulletin
|volume = 37
|issue = 2
|pages = 47–48
|issn = 1052-8091
|bibcode = 2010MPBu...37...47S
|access-date= 6 June 2018}}
|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
}}
}}
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
- {{AstDys|2456}}
- {{JPL small body}}
{{Minor planets navigator |2455 Somville |number=2456 |2457 Rublyov}}
{{Small Solar System bodies}}
{{Authority control}}
{{DEFAULTSORT:Palamedes}}