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[[Image:InnerSolarSystem-en.png|300 px|thumb|Image of the Trojan asteroids (coloured green) in front of and behind [[Jupiter]] along its orbital path.  Also shown is the main asteroid belt between the orbits of [[Mars]] and Jupiter (white) and the [[Hilda family]] of asteroids (brown).]]
The '''Jupiter Trojans''', commonly called '''Trojans''' or  '''Trojan asteroids''', are a large group of objects that share the orbit of the planet [[Jupiter]] around the Sun. Relative to Jupiter, each Trojan [[Libration|librates]] around one of the planet's two [[Lagrangian point]]s of stability, ''{{L4}}'' and ''{{L5}}'', that respectively lie 60° ahead of and behind the planet in its orbit. Trojan asteroids are distributed in two elongated, curved regions around these Lagrangian points with an average [[semi-major axis]] of about 5.2&nbsp;AU.<ref name=Yoshida2005/> 

The first Trojan, [[588 Achilles]], was discovered in 1906 by the German astronomer [[Max Wolf]].<ref name=Nicholson1961/> A total of 2,909 Jupiter Trojans have been found {{as of|2009|January|lc=on}}.<ref name=count>{{cite web |title=Trojan Minor Planets |url=http://www.cfa.harvard.edu/iau/lists/Trojans.html |publisher=International Astronomical Union (IAU) |accessdate=2009-01-22}}</ref> The name "Trojans" derives from the fact that, by convention, they each are named after a mythological figure from the [[Trojan War]]. The total number of Jupiter Trojans larger than 1&nbsp;km is believed to be about 1 million, approximately equal to the number of asteroids larger than 1&nbsp;km in the [[main asteroid belt]].<ref name=Yoshida2005/> Like main belt asteroids, Trojans form [[Asteroid family|families]].<ref name=Jewitt2004/>

Jupiter Trojans are dark bodies with reddish, featureless [[spectrum|spectra]]. No firm evidence of the presence of water, [[organic matter]] or other chemical compounds has been obtained. The Trojans' densities (as measured by studying [[Binary star|binaries]] or rotational lightcurves) vary from 0.8 to 2.5&nbsp;g·cm<sup>&minus;3</sup>.<ref name=Jewitt2004/> Trojans are thought to have been captured into their orbits during the early stages of the Solar System's formation or slightly later, during the [[planetary migration|migration]] of giant planets.<ref name=Jewitt2004/>

== Observational history ==
[[File:MaxWolf1890.jpg|thumb|right|upright|Maximilian Franz Joseph Cornelius Wolf&mdash;the discoverer of the first Trojan (1890)]]
In 1772, Italian-born mathematician [[Joseph-Louis Lagrange]], in his studies of the [[restricted three-body problem]], predicted that a small body sharing an orbit with a planet but lying 60° ahead or behind it will be trapped near these points.<ref name=Nicholson1961/> The trapped body will [[libration|librate]] slowly around the exact point of equilibrium in a [[tadpole orbit|tadpole]] or [[horseshoe orbit]].<ref name=Marzari2002/> These leading and trailing points are called the {{L4}} and {{L5}} [[Lagrange point]]s,<ref name=Jewitt2000/> respectively.{{#tag:ref|The three other points&mdash;{{L1}}, {{L2}} and {{L3}}&mdash;are unstable.<ref name=Marzari2002/>|group=Note}} However, subsequent to Lagrange's hypothesis, no asteroids trapped in Lagrange points were observed for more than a century. Those around Jupiter were the first to be found.<ref name=Nicholson1961/>
 
[[Edward Emerson Barnard|E. E. Barnard]] made the first recorded observation of a Trojan asteroid, {{mpl|(12126) 1999 RM|11}}, in 1904, but the significance of his observation was not noted at the time.<ref name=Barnard1904>{{cite web |date=1999-10-01 |title=The Earliest Observation of a Trojan |publisher=Harvard-Smithsonian Center for Astrophysics (CfA) |author=Brian G. Marsden |url=http://www.cfa.harvard.edu/iau/pressinfo/TheFirstTrojanObs.html |accessdate=2009-01-20}}</ref> Barnard believed he saw the recently discovered [[Moons of Saturn|Saturnian satellite]] [[Phoebe (moon)|Phoebe]], which was only two [[arc-minute]]s away in the sky at the time, or possibly a [[star]]. The object's identity was not realised until its orbit was constructed in 1999.<ref name=Barnard1904/>

The first true discovery of a Trojan occurred in February 1906, when astronomer [[Max Wolf]] of [[Heidelberg-Königstuhl State Observatory]] discovered an [[asteroid]] at the {{L4}} [[Lagrangian point]] of the [[Sun]]&ndash;[[Jupiter]] system, later named [[588 Achilles]].<ref name=Nicholson1961/> In 1906&ndash;1907 two more Jupiter Trojans were found by fellow German astronomer [[August Kopff]] ([[624 Hektor]] and [[617 Patroclus]]).<ref name=Nicholson1961/> Hektor, like Achilles, belonged to the {{L4}} swarm, while Patroclus was the first asteroid known to reside at the {{L5}} Lagrangian point.<ref name=Einarsson1913/> By 1938, 11 Trojans had been detected.<ref name=Wyse1938/> This number only increased to 14 by 1961.<ref name=Nicholson1961/> {{As of|2009|January}}, there are 1,634 known Trojan asteroids at {{L4}} and 1,277 at {{L5}},<ref>{{cite web|title = List of Jupiter Trojans|accessdate = 2007-08-31|url = http://cfa-www.harvard.edu/iau/lists/JupiterTrojans.html|publisher=International Astronomical Union (IAU)}}</ref> but the rate of discovery is growing rapidly as instruments improve: in January 2000, a total of 257 had been discovered;<ref name=Jewitt2000/> by May 2003, that number had grown to 1,600.<ref name=Fernandes2003/>

===Nomenclature===
The custom of naming all asteroids in Jupiter's {{L4}} and {{L5}} points after famous heroes of the Trojan War was suggested by [[Johann Palisa]] of [[Vienna]], who was the first to accurately calculate their orbits.<ref name=Nicholson1961/> Asteroids in the {{L4}} group are named after [[Greece|Greek]] heroes (the "Greek node or camp" or "Achilles group"), and those at the {{L5}} point are named after the heroes of [[Troy]] (the "Trojan node or camp").<ref name=Nicholson1961/> Confusingly, 617 Patroclus was named before the Greece/Troy rule was devised, and a Greek name thus appears in the Trojan node; the Greek node also has one "misplaced" asteroid, 624 Hektor, named after a Trojan hero.<ref name=Wyse1938/>

The term "[[Trojan (astronomy)|Trojan]]" also is used to refer to other [[small solar system body|small Solar System bodies]] with similar relationships to larger bodies: for example, there are both [[Trojan (astronomy)|Mars Trojans]] and [[Neptune Trojan]]s, and Saturn has [[Trojan moon]]s.{{#tag:ref|Simulations suggest Saturn and Uranus have few if any Trojans.<ref name="Nep">{{cite journal|last=Sheppard|first=SS |coauthors=CA Trujillo|date=2006-07-28|title=A thick cloud of Neptune Trojans and their colors|journal=Science|location=New York|volume=313|issue=5786|pages=511&ndash;514|issn=0036-8075|oclc=110021198|url=http://www.ciw.edu/users/sheppard/pub/Sheppard06NepTroj.pdf}}</ref> The term "Trojan asteroid" is normally understood to specifically mean the Jupiter Trojans since the first Trojans were discovered near Jupiter's orbit and Jupiter currently has by far the most known Trojans.<ref name=count/>|group=Note}}

==Numbers and mass==
[[Image:Lagrange points.jpg|thumb|right|A contour plot of Earth's Lagrangian points: {{L4}} and {{L5}} can be seen above and below the planet. Jupiter's Lagrangian points are similar, but far larger.]]
Estimates of the total number of Trojans are based on deep surveys of limited areas of the sky.<ref name=Yoshida2005/> The {{L4}} swarm is believed to hold between 160&ndash;240,000 asteroids with diameters larger than 2&nbsp;km and 600,000 with diameters larger than 1&nbsp;km.<ref name=Yoshida2005/><ref name=Jewitt2000/> If the {{L5}} swarm contains a comparable number of objects, there are more than 1 million Trojans. These numbers are similar to that of comparable asteroids in the main asteroid belt.<ref name=Yoshida2005/> The total mass of the Trojans is estimated at 0.0001 of the mass of Earth or one-fifth of the mass of the main asteroid belt.<ref name=Jewitt2000/> The number of Trojans probably is known completely for those of [[absolute magnitude]] 9.0&ndash;9.5.<ref name=Jewitt2004/> The number of Trojans observed in the {{L4}} swarm is slightly larger than that observed in {{L5}}; however, since the brightest Trojans show little variation in numbers between the two populations, this disparity is probably due to an observational bias.<ref name=Jewitt2004/> However some models indicate that the {{L4}} swarm may be slightly more stable than the {{L5}} swarm.<ref name=Marzari2002/>

The largest of the Trojans is [[624 Hektor]], which has an average radius of 101.5&nbsp;±&nbsp;1.8&nbsp;km.<ref name=Fernandes2003/> There are few large Trojans in comparison to the overall population. The number of Trojans grows very quickly with decreasing size down to 84&nbsp;km, much more so than in the main asteroid belt. The 84&nbsp;km diameter corresponds to an absolute magnitude of 9.5, assuming an [[albedo]] of 0.04. Within the 4.4&ndash;40&nbsp;km range the Trojans' size distribution resembles that of the main belt asteroids. An absence of data means that nothing is known about the masses of the smaller Trojans.<ref name=Marzari2002/> This distribution suggests that the smaller Trojans are the products of collisions by larger Trojans.<ref name=Jewitt2004/>

==Orbits==
[[Image:AnimatedOrbitOf624Hektor.gif|thumb|Animation of the orbit of 624 Hektor (blue), set against the orbit of Jupiter (red)]]
The Jupiter Trojans have orbits with radii in between 5.05&nbsp;AU and 5.35&nbsp;AU (mean semi-major axis is 5.2&nbsp;±&nbsp;0.15&nbsp;AU), and are distributed throughout elongated, curved regions around the two Lagrangian points;<ref name=Yoshida2005/> each swarm stretches for about 26° along the orbit of Jupiter, amounting to a total distance of about 2.5&nbsp;AU.<ref name=Jewitt2000/> The width of the swarms approximately equals two [[Hill radius|Hill's radii]], which in the case of Jupiter amounts to about 0.6&nbsp;AU.<ref name=Marzari2002/> Many of Jupiter's Trojans have large [[orbital inclination]]s relative to the orbital plane of the planet&mdash;up to 40°.<ref name=Jewitt2000/> 

The Trojans do not maintain a fixed separation from Jupiter. They slowly librate around their respective equilibrium points, periodically moving closer to Jupiter or further from it.<ref name=Marzari2002/> Trojans generally follow paths called [[tadpole orbit]]s around the Lagrangian points; the average period of their libration is about 150 years.<ref name=Jewitt2000/> The amplitude of the libration (along the Jovian orbit) varies from 0.6° to 88°, with the average being about 33°.<ref name=Marzari2002/> Simulations showed that Trojans can follow even more complicated trajectories when moving from one Lagrangian point to another&mdash;these are called [[horseshoe orbit]]s (currently no Jupiter Trojan with such an orbit is known).<ref name=Marzari2002/>

===Dynamical families and binaries===
Discerning [[collisional family|dynamical families]] within the Trojan population is more difficult than it is in the asteroid belt, because the Trojans are locked within a far narrower range of possible positions than the main belt asteroids. This means that clusters tend to overlap and merge with the overall swarm. However, as of 2003 roughly a dozen dynamical families have been identified within the Trojans. Trojan families are much smaller in size than families in the main belt; the largest identified family, the Menelaus group, consists of only eight members.<ref name=Jewitt2004/> 

Only one Trojan [[binary asteroid]],  [[617 Patroclus]], has been identified to date. The binary's orbit is extremely close, at 650&nbsp;km, compared to 35,000&nbsp;km for the primary's [[Hill sphere]].<ref name=Marchis2006/> The largest Trojan asteroid—624 Hektor—likely is a [[contact binary (asteroid)|contact binary]] too.<ref name=Jewitt2004/><ref name=Lacerda2007/>

==Physical properties==
Jupiter Trojans are dark bodies of irregular shape. Their [[geometric albedo]]s generally vary between 3 and 10%.<ref name=Fernandes2003/> The average value is 0.056&nbsp;±&nbsp;0.003.<ref name=Jewitt2004/> The asteroid [[4709 Ennomos]] has the highest albedo (0.18) of all Trojans.<ref name=Fernandes2003/> Little is known about the masses, chemical composition, rotation or other physical properties of the Trojans.<ref name=Jewitt2004/>

=== Rotation ===
The rotational properties of Trojans are not well known. Analysis of the rotational [[light curve]]s of 72 Trojan asteroids gave an average rotational period of about 11.2&nbsp;hours, whereas the average period of the control sample of the main belt asteroids was 10.6&nbsp;hours.<ref name=Barucci2002/> The distribution of the rotational periods of Trojans appeared to be well approximated by a [[Maxwell distribution|Maxwellian function]],<ref group=Note>The Maxwellian function is <math>F=\begin{smallmatrix}\frac{1}{\sqrt{2\pi}\sigma}\exp(-(P-P_0)^2/\sigma^2)\end{smallmatrix}</math>, where <math>P_0</math> is the average rotational period, <math>\sigma</math> is the [[Statistical dispersion|dispersion]] of periods.</ref> whereas the similar distribution of main belt asteroids was found to be non-Maxwellian with a deficit of asteroids with periods in the range 8&ndash;10&nbsp;hours.<ref name=Barucci2002/> The Maxwellian distribution of the rotational periods of Trojans may indicate that they have undergone a stronger collisional evolution compared to the main belt.<ref name=Barucci2002/>

However in 2008 a team from [[Calvin College]] analyzed the [[light curve]]s of a debiased sample of ten Trojans, and found a [[median]] spin period of 18.9 hours. This value was significantly lower than the value for main belt asteroids of similar size (11.5 hours). The difference could mean that the Trojans possess a lower average density, which may imply that they formed in the [[Kuiper belt]] (see below).<ref>{{cite journal|last=Molnar| first=Lawrence A.|coauthors=Melissa J. Haegert, and Kathleen M. Hoogeboom|date=2008 April|title=Lightcurve Analysis of an Unbiased Sample of Trojan Asteroids|journal=The Minor Planet Bulletin|publisher=Association of Lunar and Planetary Observers|volume=35|pages=82&ndash;84|oclc=85447686|url=http://adsabs.harvard.edu/abs/2008MPBu...35...82M}}</ref>

=== Composition ===
[[Spectroscopy|Spectroscopically]], the Jupiter Trojans mostly are [[D-type asteroid]]s, which predominate in the outer regions of the main belt.<ref name=Jewitt2004/> A small number are classified as [[P-type asteroid|P]] or [[C-type asteroid]]s.<ref name=Barucci2002/> Their spectra are red (meaning that they reflect light at longer wavelengths) or neutral and featureless.<ref name=Fernandes2003/> No firm evidence of water, organics or other chemical compounds has been obtained {{as of|2008|lc=on}}, though [[4709 Ennomos]] has an albedo slightly higher than the Trojan average, which may indicate the presence of water ice. In addition, a number of other Trojans, such as [[911 Agamemnon]] and [[617 Patroclus]], have shown very weak absorptions at 1.7 and 2.3&nbsp;μm, which might indicate the presence of organics.<ref>{{cite journal|title=Spectroscopic Search for Water Ice on Jovian Trojan Asteroids|author=Yang, Bin and Jewitt, David|year=2007|journal=The Astronomical Journal|volume= 134|pages=223&ndash;228|doi=10.1086/518368|url=http://www.iop.org/EJ/abstract/1538-3881/134/1/223/|accessdate=2009-01-19}}</ref>  The Trojans' spectra are similar to those of the [[Moons of Jupiter#Irregular satellites|irregular moons of Jupiter]] and, to certain extent, [[comet nuclei]], though Trojans are spectrally very different from the redder [[Kuiper belt object]]s.<ref name=Yoshida2005/><ref name=Jewitt2004/> A Trojan's spectrum can be matched to a mixture of water ice, a large amount of carbon-rich material ([[charcoal]]),<ref name=Jewitt2004/> and possibly [[magnesium]]-rich [[silicate]]s.<ref name=Barucci2002/> The composition of the Trojan population appears to be markedly uniform, with little or no differentiation between the two swarms.<ref>{{cite journal|title=The surface composition of Jupiter Trojans: Visible and near-infrared survey of dynamical families|author=Dotto, E., Fornasier, S., Barucci,  M.A., et al.|journal=Icarus|volume=183,|issue=2|date= August 2006|pages= 420&ndash;434|doi=10.1016/j.icarus.2006.02.012|url=http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WGF-4JT38N8-3&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=b23513f67484eaff2979db06148e99a5|accessdate=2009-01-17}}</ref> 

A team from the [[Keck Observatory]] in Hawaii announced in 2006 that it had measured the density of the binary Trojan asteroid [[617 Patroclus]] as being less than that of water ice (0.8&nbsp;g/cm<sup>3</sup>), suggesting that the pair, and possibly many other Trojan objects, more closely resemble [[comet]]s or [[Kuiper belt]] objects in size and composition&mdash;water ice with a layer of dust&mdash;than they do the main belt asteroids.<ref name=Marchis2006/> Countering this argument, the density of Hektor as determined from its rotational lightcurve (2.480&nbsp;g/cm<sup>3</sup>) is significantly higher than that of 617 Patroclus.<ref name=Lacerda2007/> Such a difference in densities is puzzling and indicates that density may not be a good indicator of asteroid origin.<ref name=Lacerda2007/>

==Origin and evolution==
Two main theories have emerged to explain the formation and evolution of the Trojans. The first suggests that the Trojans formed in the same part of the [[Solar System]] as Jupiter and entered their orbits while the planet was forming.<ref name=Marzari2002/> The last stage of Jupiter's formation involved runaway growth of its mass through the accretion of large amounts of [[hydrogen]] and [[helium]] from the [[protoplanetary disk]]; during this growth, which lasted for only about 10,000 years, the mass of Jupiter increased by a factor of ten. The [[planetesimal]]s that had approximately the same orbits as Jupiter were caught by the increased gravity of the planet.<ref name=Marzari2002/> The capture mechanism was very efficient&mdash;about 50% of all remaining planetesimals were trapped. This hypothesis has two major problems: the number of trapped bodies exceeds the observed population of Trojans by four [[order of magnitude|orders of magnitude]], and the present Trojan asteroids have larger orbital inclinations than are predicted by the capture model.<ref name=Marzari2002/> However, simulations of this scenario show that such a mode of formation also would inhibit the creation of similar Trojans around [[Saturn]], and this has been born out by observation: to date no Trojans have been found around Saturn.<ref>{{cite journal|title=The growth of Jupiter and Saturn and the capture of Trojans|last=Marzari|first=F.|last=Scholl|first=H.|journal=Astronomy and Astrophysics|volume=339|pages=278&ndash;285|year=1998|url=http://adsabs.harvard.edu/abs/1998A&A...339..278M|accessdate=2008-01-17}}</ref> 

The second theory, part of the [[Nice model]], proposes that the Trojans were captured during [[planetary migration]], which happened about 500&ndash;600 million years after the Solar System's formation.<ref name=Levison2007/> The migration was triggered by the passage of Jupiter and Saturn through the 1:2 mean motion [[orbital resonance|resonance]]. During it [[Uranus]], [[Neptune]] and to some extent Saturn moved outward, while Jupiter moved slightly inward.<ref name=Levison2007/> Migrating giant planets destabilized the primordial [[Kuiper belt]] throwing millions of objects into the inner Solar System. In addition, their combined gravitational influence quickly would have disturbed any pre-existing Trojans.<ref name=Levison2007/> Under this theory, the present Trojan population eventually accumulated from those runaway Kuiper belt objects as Jupiter and Saturn moved away from the resonance.<ref name="Morbidelli">{{cite journal|last=Morbidelli|first=A.|coauthors=Levison, HF; Tsiganis, K; Gomes, R|date=2005-05-26|title=Chaotic capture of Jupiter's Trojan asteroids in the early Solar System|journal=Nature|volume=435|issue=7041|pages=462&ndash;465|issn=0028-0836|oclc=112222497|url=http://www.oca.eu/michel/PubliGroupe/MorbyNature2005.pdf}}</ref> 

The long-term future of the Trojans is open to question, as multiple weak resonances with Jupiter and Saturn cause them to behave chaotically over time.<ref name=Robutal2005/> In addition, collisional shattering slowly depletes the Trojan population as fragments are ejected. Ejected Trojans could become temporary satellites of Jupiter or [[Jupiter family comet]]s.<ref name=Jewitt2004/> Simulations show that up to 17% of Jupiter's Trojans are unstable over the age of the Solar System, and so must have been ejected from their orbits at some time before now.<ref>{{cite journal|title=Chaotic Diffusion And Effective Stability of Jupiter Trojans |author=Kleomenis Tsiganis, Harry Varvoglis and Rudolf Dvorak|year=2004|publisher=Springer|journal=Celestial Mechanics and Dynamical Astronomy|volume=92|number=1&ndash;3|date=April, 2005|doi=10.1007/s10569-004-3975-7|pages=71&ndash;87|url=http://www.springerlink.com/content/vp38717557064k15/|accessdate=2009-01-17}}</ref> Levison et al. believe that roughly 200 ejected Trojans greater than 1&nbsp;km in diameter might be traveling the Solar System, with a few possibly on Earth-crossing orbits.<ref name=Levison1997>{{cite journal|title=Dynamical evolution of Jupiter's Trojan asteroids|author=Levison, Harold F.; Shoemaker, Eugene M.; Shoemaker, Carolyn S.|journal=Nature|volume=385|pages=42&ndash;44|year=1997|doi=10.1038/385042a0|url=http://www.nature.com/nature/journal/v385/n6611/abs/385042a0.html|accessdate=2009-01-19}}</ref> Some of the escaped Trojans may become [[Jupiter family comet]]s as they approach the Sun and their surface ice begins evaporating.<ref name=Levison1997/>

== See also ==
{{colbegin}}
* [[List of Trojan asteroids (Greek camp)]]
* [[List of Trojan asteroids (Trojan camp)]]
* [[Trojan pronunciation|Pronunciation of Trojan asteroid names]]
* [[List of objects at Lagrangian points]]
* [[List of Jupiter-crossing minor planets]]
* [[Comet Shoemaker-Levy 9]]
{{colend}}

== Notes ==
<references group=Note/>

== References ==
{{Source list
|name1=Jewitt2000
|ref1={{cite journal|last=Jewitt|first=David C.|coauthors=Trujillo, Chadwick A.; Luu, Jane X.|title=Population and size distribution of small Jovian Trojan asteroids|year=2000|journal=The Astronomical journal|volume=120|pages=1140&ndash;7|doi=10.1086/301453|url=http://adsabs.harvard.edu/abs/2000AJ....120.1140J}}
|name2=Yoshida2005
|ref2={{cite journal|last=Yoshida|first=F.|coauthors=Nakamura, T|title=Size distribution of faint {{L4}} Trojan asteroids|year=2005|journal=The Astronomical journal|volume=130|pages=2900&ndash;11|doi=
10.1086/497571|url=http://adsabs.harvard.edu/abs/2005AJ....130.2900Y}}
|name3=Wyse1938
|ref3={{cite journal|last=Wyse|first=A.B.|title=The Trojan group|year=1938|journal=Astronomical Society of the Pacific Leaflets|volume=3|pages=113&ndash;19|url=http://adsabs.harvard.edu/abs/1938ASPL....3..113W}}
|name4=Einarsson1913
|ref4={{cite journal|last=Einarsson|first=Sturla|title=The Minor Planets of the Trojan Group|year=1913|journal=Publications of the Astronomical Society of the Pacific|volume=25|pages=131&ndash;3|url=http://adsabs.harvard.edu/abs/1913PASP...25..131E}}
|name5=Nicholson1961
|ref5={{cite journal|last=Nicholson|first=Seth B.|title=The Trojan asteroids|year=1961|journal=Astronomical Society of the Pacific Leaflets|volume=8|pages=239&ndash;46|url=http://adsabs.harvard.edu/abs/1961ASPL....8..239N}}
|name6=Marzari2002
|ref6={{cite book|last=Marzari|first=F.|coauthors=Scholl, H.; Murray C.; Lagerkvist C.|year=2002 |chapter=Origin and Evolution of Trojan Asteroids|title=Asteroids III|publisher=University of Arizona Press|pages=725&ndash;38|location=Tucson, Arizona| url=http://www.lpi.usra.edu/books/AsteroidsIII/pdf/3007.pdf|format=PDF}}
|name7=Barucci2002
|ref7={{cite book|last=Barucci|first=M.A.|coauthors=Kruikshank, D.P.; Mottola S.; Lazzarin M.|year=2002 |chapter=Physical Properties of Trojan and Centaur Asteroids|title=Asteroids III|publisher=University of Arizona Press|pages=273&ndash;87|location=Tucson, Arizona}}
|name8=Levison2007
|ref8={{cite journal | author=Harold F. Levison, Alessandro Morbidelli, Crista Van Laerhoven et al. | title=Origin of the Structure of the Kuiper Belt during a Dynamical Instability in the Orbits of Uranus and Neptune|year=2007| url=http://adsabs.harvard.edu/abs/2007arXiv0712.0553L | id={{arxiv|0712.0553}} }}
|name9=Marchis2006
|ref9={{cite journal|last=Marchis|first=Franck|coauthors=Hestroffer, Daniel; Descamps, Pascal ''et al.''|title=A low density of 0.8&nbsp;g&nbsp;cm<sup>&minus;3</sup> for the Trojan binary asteroid 617 Patroclus|year=2006|journal=Nature|volume=439|issue=7076|pages=565&ndash;567|url=http://adsabs.harvard.edu/abs/2006Natur.439..565M|doi=10.1038/nature04350}}
|name10=Fernandes2003
|ref10={{cite journal|last=Fernandes|first=Yanga R.|coauthors=Sheppard, Scott S.; Jewitt, David C.|title=The albedo distribution of Jovian Trojan asteroids|year=2003|journal=The Astronomical Journal|volume=126|pages=1563&ndash;1574|url=http://adsabs.harvard.edu/abs/2003AJ....126.1563F|doi=10.1086/377015}}
}}
{{Source list
|name1=Lacerda2007
|ref1={{cite journal|last=Lacerda|first=Pedro|coauthors=Jewitt, David C.|title=Densities of Solar System Objects from Their Rotational Light Curves|year=2007|journal=The Astronomical journal|volume=133|pages=1393&ndash;1408|doi=
10.1086/511772|url=http://adsabs.harvard.edu/abs/2007AJ....133.1393L}}
|name2=Jewitt2004
|name3=Robutal2005
|ref3={{cite journal|last=Robutal|first=P.|coauthors=Gabern, F.; Jorba A.|title=The observed trojans and the global dynamics around the lagrangian points of the sun–jupiter system|year=2005|journal=Celestial Mechanics and Dynamical Astronomy|volume=92|pages=53&ndash;69|doi=10.1007/s10569-004-5976-y|url=http://www.cds.caltech.edu/~gabern/preprints/osterreich.pdf|format=PDF}}
}}
{{reflist|2}}

== External links ==
* {{cite web|url=http://cfa-www.harvard.edu/iau/lists/Trojans.html|title=Minor Planet Center's List of Trojan Minor Planets}}
* {{cite web|url=http://www.newscientistspace.com/article.ns?id=dn9340&feedId=online-news_rss20|title=New Trojan asteroid hints at huge Neptunian cloud|publisher=New Scientist}}
* {{cite web|last=Sheppard|first=Scott|url=http://www.dtm.ciw.edu/users/sheppard/satellites/trojan.html|title=The Trojan Page}}

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[[Category:Jupiter Trojans| ]]

[[be-x-old:Траянскі астэроід]]
[[ca:Asteroide troià]]
[[cs:Troján]]
[[da:Trojanske asteroider]]
[[de:Trojaner (Astronomie)]]
[[es:Asteroide troyano]]
[[fr:Astéroïde troyen]]
[[ko:트로이 소행성군]]
[[hr:Trojanski asteroid]]
[[it:Asteroidi troiani di Giove]]
[[lb:Trojaner (Astronomie)]]
[[nl:Trojanen-planetoïden]]
[[ja:トロヤ群]]
[[no:Jupitertrojan]]
[[nn:Jupitertrojan]]
[[pl:Trojańczycy]]
[[pt:Asteroide troiano]]
[[ru:Троянские астероиды]]
[[simple:Trojan asteroid]]
[[sk:Trójan (planétka)]]
[[sl:Trojanski asteroid]]
[[fi:Troijalainen asteroidi]]
[[sv:Trojanerna]]
[[tr:Troyalı göktaşları]]
[[zh:特洛伊小行星]]