1404 Ajax
{{Short description|Asteroid}}
{{Use dmy dates|date=June 2018}}
{{Infobox planet
| minorplanet = yes
| name = 1404 Ajax
| background = #C2FFFF
| image = 001404-asteroid shape model (1404) Ajax.png
| image_scale =
| caption = Modelled shape of Ajax from its lightcurve
| discoverer = K. Reinmuth
| discovery_site = Heidelberg Obs.
| discovered = 17 August 1936
| mpc_name = (1404) Ajax
| alt_names = 1936 QW
| adjective = Ajantian {{IPAc-en|ə|ˈ|dZ|æ|n|t|i|ə|n}}
| pronounced = {{IPAc-en|ˈ|eɪ|dʒ|æ|k|s}}'Polydamas' in Noah Webster (1884) A Practical Dictionary of the English Language
| named_after = Ajax {{small|(Greek mythology)}}
| mp_category = Jupiter trojan
{{nowrap|Greek{{·}}background}}
| epoch = 23 March 2018 (JD 2458200.5)
| uncertainty = 0
| observation_arc = 81.76 yr (29,864 d)
| aphelion = 5.9044 AU
| perihelion = 4.6992 AU
| semimajor = 5.3018 AU
| eccentricity = 0.1137
| period = 12.21 yr (4,459 d)
| mean_anomaly = 247.16°
| mean_motion = {{Deg2DMS|0.0807|sup=ms}} / day
| inclination = 18.005°
| asc_node = 332.92°
| arg_peri = 59.772°
| jupiter_moid = 0.0433 AU
| tisserand = 2.8890
| mean_diameter = {{val|81.43|ul=km}} {{small|(derived)}}
{{val|81.69|3.2|u=km}}
{{val|83.99|1.28|u=km}}
{{val|96.34|2.25|u=km}}
| rotation = {{val|28.4|ul=h}}
{{val|29.38|0.01|u=h}}
{{val|34|u=h}}
| albedo = {{val|0.048|0.009}}
{{val|0.050|0.003}}
{{val|0.0508}} {{small|(derived)}}
{{val|0.0665|0.005}}
| spectral_type = C {{small|(assumed)}}
V–I {{=}} {{val|0.960|0.032}}
| abs_magnitude = 9.00
9.3
{{val|9.87|0.47}}
}}
1404 Ajax {{IPAc-en|ˈ|eɪ|dʒ|æ|k|s}} is a carbonaceous Jupiter trojan from the Greek camp, approximately {{convert|83|km|mi|abbr=off|sigfig=2|sp=us}} kilometers in diameter. It was discovered on 17 August 1936, by German astronomer Karl Reinmuth at Heidelberg Observatory in southern Germany, and named after the legendary warrior Ajax from Greek mythology. The assumed C-type asteroid belongs to the 40 largest Jupiter trojans and has a longer than average rotation period of 29.4 hours.
Orbit and classification
Ajax is a C-type asteroid, that orbits in the leading Greek camp at Jupiter's {{L4}} Lagrangian point, 60° ahead of its orbit (see Trojans in astronomy). It is also a non-family asteroid in the Jovian background population. Jupiter trojans are thought to have been captured into their orbits during or shortly after the early stages of the formation of the Solar System. More than 4,500 Jupiter trojans in the Greek camp and 7,000 in total have been discovered.
Ajax orbits the Sun at a distance of 4.7–5.9 AU once every 12 years and 3 months (4,459 days; semi-major axis of 5.3 AU). Its orbit has an eccentricity of 0.11 and an inclination of 18° with respect to the ecliptic plane. The body's observation arc begins at Heidelberg 6 days after its official discovery observations in August 1936.
Physical characteristics
Ajax is an assumed, carbonaceous C-type asteroid, while its V–I color index of 0.96 agrees with most D-type asteroids, which is the dominant spectral type among the large Jupiter trojans.
= Rotation period =
In December 2010, a rotational lightcurve of Ajax was obtained from photometric observations taken by Robert Stephens at the Goat Mountain Astronomical Research Station {{Obscode|G79}} in California. Lightcurve analysis gave a rotation period of 29.38 hours with a brightness variation of 0.30 magnitude ({{small|U=3-}}), superseding fragmentary photometric measurements by Richard P. Binzel (1988), and by Roberto Crippa and Federico Manzini (2009) at the Sozzago Astronomical Station {{Obscode|A12}}, which gave a period of 28.4 and 34 hours, respectively ({{small|U=1/2-}}).
= Diameter and albedo =
According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Ajax measures between 81.69 and 96.34 kilometers in diameter and its surface has an albedo between 0.048 and 0.0665. The Collaborative Asteroid Lightcurve Link derives an albedo of 0.0508 and a diameter of 81.43 kilometers based on an absolute magnitude of 9.3.
{{Largest Jupiter trojans}}
Naming
This minor planet was named for Ajax the Great, a Greek warrior of great strength and courage in the Trojan War. He is the half brother of Teucer and son of king Telamon, who kills himself because Achilles{{'}} armor was awarded to Odysseus. The Jupiter trojans {{mp|588 Achilles}}, {{mp|1143 Odysseus}} and {{mp|1749 Telamon}} and {{mp|2797 Teucer}} are all named after these figures from Greek mythology. The official naming of Ajax was first cited in The Names of the Minor Planets by Paul Herget in 1955 ({{small|H 127}}).
References
{{reflist|30em|refs=
|type = 2018-05-23 last obs.
|title = JPL Small-Body Database Browser: 1404 Ajax (1936 QW)
|url = https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2001404
|publisher = Jet Propulsion Laboratory
|access-date = 13 June 2018}}
|last = Schmadel | first = Lutz D.
|title = Dictionary of Minor Planet Names |publisher = Springer Berlin Heidelberg
|page = 113
|date = 2007
|isbn = 978-3-540-00238-3
|doi = 10.1007/978-3-540-29925-7_1405 |chapter = (1404) Ajax }}
|title = 1404 Ajax (1936 QW)
|work = Minor Planet Center
|url = https://www.minorplanetcenter.net/db_search/show_object?object_id=1404
|access-date = 13 June 2018}}
|title = List of Jupiter Trojans
|work = Minor Planet Center
|date = 30 May 2018
|url = https://www.minorplanetcenter.net/iau/lists/JupiterTrojans.html
|access-date = 13 June 2018}}
|title = Asteroids and comets rotation curves – (1404) Ajax
|last = Behrend |first = Raoul
|publisher = Geneva Observatory
|url = http://obswww.unige.ch/~behrend/page4cou.html#001404
|access-date = 11 January 2017}}
|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=01404 online catalog])
|title = Asteroid (1404) Ajax – Proper elements
|publisher = AstDyS-2, Asteroids – Dynamic Site
|url = https://newton.spacedys.com/astdys/index.php?n=1404&pc=1.1.6
|access-date = 13 June 2018}}
|title = Asteroid 1404 Ajax
|work = Small Bodies Data Ferret
|url = https://sbntools.psi.edu/ferret/SimpleSearch/results.action?targetName=1404+Ajax
|access-date = 13 June 2018
|archive-date = 13 June 2018
|archive-url = https://web.archive.org/web/20180613112035/https://sbntools.psi.edu/ferret/SimpleSearch/results.action?targetName=1404%20Ajax
|url-status = dead
}}
|title = LCDB Data for (1404) Ajax
|publisher = Asteroid Lightcurve Database (LCDB)
|url = http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=1404%7CAjax
|access-date = 13 June 2018}}
|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}}
|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=1404 online], [https://core.ac.uk/download/pdf/43545172.pdf AcuA catalog p. 153])
|first1 = Richard P. |last1 = Binzel
|first2 = Linda M. |last2 = Sauter
|date = February 1992
|title = Trojan, Hilda, and Cybele asteroids – New lightcurve observations and analysis
|url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=1992Icar...95..222B
|journal = Icarus
|volume = 95
|issue = 2
|pages = 222–238
|issn = 0019-1035
|bibcode = 1992Icar...95..222B
|doi = 10.1016/0019-1035(92)90039-A
|access-date= 11 January 2017}}
|first1 = Linda M. |last1 = French
|first2 = Robert D. |last2 = Stephens
|first3 = Susan M. |last3 = Lederer
|first4 = Daniel R. |last4 = Coley
|first5 = Derrick A. |last5 = Rohl
|date = April 2011
|title = Preliminary Results from a Study of Trojan Asteroids
|url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2011MPBu...38..116F
|journal = The Minor Planet Bulletin
|volume = 38
|issue = 2
|pages = 116–120
|issn = 1052-8091
|bibcode = 2011MPBu...38..116F
|access-date= 11 January 2017}}
|display-authors = 6
|first1 = Peter |last1 = Veres
|first2 = Robert |last2 = Jedicke
|first3 = Alan |last3 = Fitzsimmons
|first4 = Larry |last4 = Denneau
|first5 = Mikael |last5 = Granvik
|first6 = Bryce |last6 = Bolin
|first7 = Serge |last7 = Chastel
|first8 = Richard J. |last8 = Wainscoat
|first9 = William S. |last9 = Burgett
|first10 = Kenneth C. |last10 = Chambers
|first11 = Heather |last11 = Flewelling
|first12 = Nick |last12 = Kaiser
|first13 = Eugen A. |last13 = Magnier
|first14 = Jeff S. |last14 = Morgan
|first15 = Paul A. |last15 = Price
|first16 = John L. |last16 = Tonry
|first17 = Christopher |last17 = Waters
|date = November 2015
|title = Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 – Preliminary results
|journal = Icarus
|volume = 261
|pages = 34–47
|bibcode = 2015Icar..261...34V
|doi = 10.1016/j.icarus.2015.08.007
|arxiv = 1506.00762|s2cid = 53493339 }}
}}
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|1404}}
- {{JPL small body}}
{{Minor planets navigator |1403 Idelsonia |number=1404 |1405 Sibelius}}
{{Small Solar System bodies}}
{{Authority control}}
{{DEFAULTSORT:Ajax}}