Jupiter trojan

{{short description|Asteroid sharing the orbit of Jupiter}} {{Use dmy dates|date=October 2019}} [[File:InnerSolarSystem-en.png|thumb|upright=1.4|The asteroids of the inner Solar System and Jupiter {| style="width: 90%; margin: 4px 0 4px 20px;" |- | valign=top | {{legend2|#6ad768|border=1px solid #2B9929|'''''Jupiter trojans'''''}} {{legend2|#d39300|border=1px solid #855D00|Hilda asteroids}} | valign=top | {{legend2|#e9e9e9|border=1px solid #999999|Asteroid belt}} {{legend2|#007DD6|border=1px solid #00508A|Orbits of planets}} |} The Jupiter trojans are divided into two groups: The Greek camp in front of and the Trojan camp trailing behind Jupiter in their orbit. ]]

The '''Jupiter trojans''', commonly called '''trojan asteroids''' or simply '''trojans''', are a large group of asteroids that share the planet Jupiter's orbit around the Sun. Relative to Jupiter, each trojan librates around one of Jupiter's stable Lagrange points: either ''{{L4|nolink=yes}}'', existing 60° ahead of the planet in its orbit, or ''{{L5|nolink=yes}}'', 60° behind. Jupiter trojans are distributed in two elongated, curved regions around these Lagrangian points with an average semi-major axis of about 5.2 AU.<ref name=Yoshida2005/>

The first Jupiter trojan discovered, 588 Achilles, was spotted in 1906 by German astronomer Max Wolf.<ref name=Nicholson1961/> More than 15,300 Jupiter trojans have been found {{as of|2025|10|lc=on}}.<ref name="MPC-Trojan-count" /> By convention, they are each named from Greek mythology after a figure of the Trojan War, hence the name "trojan". The total number of Jupiter trojans larger than 1 km in diameter is believed to be about {{Nowrap|1 million}},<ref name=Yoshida2005/> approximately equal to the number of asteroids larger than 1 km in the asteroid belt.<ref>{{cite journal | last1=Tedesco | first1=E. F. | last2=Desert | first2=F.-X. | title=The Infrared Space Observatory Deep Asteroid Search | journal=The Astronomical Journal | year=2002 | volume=123 | issue=4 | pages=2070–2082 | bibcode=2002AJ....123.2070T| doi=10.1086/339482 | doi-access=free }}</ref> Like main-belt asteroids, Jupiter trojans form families.<ref name=Jewitt2004/>

{{As of|2004}}, many Jupiter trojans showed to observational instruments as dark bodies with reddish, featureless spectra. No firm evidence of the presence of water, or any other specific compound on their surface has been obtained, but it is thought that they are coated in tholins, organic polymers formed by the Sun's radiation.<ref name="Dotto2006" /> The Jupiter trojans' densities (as measured by studying binaries or rotational lightcurves) vary from 0.8 to 2.5 g·cm−3.<ref name=Jewitt2004/> Jupiter 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 migration of giant planets.<ref name=Jewitt2004/>

The term "Trojan asteroid" specifically refers to the asteroids co-orbital with Jupiter, but the general term "trojan" is sometimes more generally applied to other small Solar System bodies with similar relationships to larger bodies: Mars trojans, Neptune trojans, Uranus trojans and Earth trojans are known to exist.<ref name="Nep">{{cite journal|last=Sheppard|first=S. S.|author2=C. A. Trujillo|date=28 July 2006|title=A thick cloud of Neptune Trojans and their colors|journal=Science|location=New York|volume=313|issue=5786|pages=511–514|oclc=110021198|doi=10.1126/science.1127173|pmid=16778021|bibcode=2006Sci...313..511S|s2cid=35721399 |url=http://pdfs.semanticscholar.org/8108/b7ca960285556143472a74bdf6d1ef4f4b4b.pdf|archive-url=https://web.archive.org/web/20200412144806/http://pdfs.semanticscholar.org/8108/b7ca960285556143472a74bdf6d1ef4f4b4b.pdf|url-status=dead|archive-date=12 April 2020}}</ref><ref>{{Cite web |url=http://www.nasa.gov/mission_pages/WISE/news/wise20110727.html |title=NASA's WISE Mission Finds First Trojan Asteroid Sharing Earth's Orbit 27 July 2011 |access-date=29 July 2011 |archive-url=https://web.archive.org/web/20170502055548/https://www.nasa.gov/mission_pages/WISE/news/wise20110727.html |archive-date=2 May 2017 |url-status=live }}</ref><ref>{{cite journal|last1=Connors|first1=Martin|first2=Paul|last2=Wiegert|first3=Christian|last3=Veillet|title=Earth's Trojan asteroid|journal=Nature|volume=475|issue=7357|pages=481–483|date=28 July 2011|doi=10.1038/nature10233|bibcode=2011Natur.475..481C|pmid=21796207|s2cid=205225571 }}</ref> Temporary Venus trojans and Saturn trojans exist, as well as for 1 Ceres and 4 Vesta. The term "Trojan asteroid" is normally understood to specifically mean the Jupiter trojans because the first Trojans were discovered near Jupiter's orbit and Jupiter currently has by far the most known Trojans.<ref name="MPC-Trojan-count" />

== Observational history == [[File:Maximilian Franz Joseph Cornelius Wolf.jpg|thumb|right|upright|Maximilian Franz Joseph Cornelius Wolf (1890)—the discoverer of the first trojan]]

In 1772, Italian-born mathematician Joseph-Louis Lagrange, in studying 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 librate slowly around the point of equilibrium in a tadpole or horseshoe orbit.<ref name=Marzari2002/> These leading and trailing points are called the {{L4|nolink=yes}} and {{L5|nolink=yes}} Lagrange points.<ref name=Jewitt2000/>{{refn|The three other points—L1, L2 and L3—are unstable.<ref name=Marzari2002/>|group=Note}} The first asteroids trapped in Lagrange points were observed more than a century after Lagrange's hypothesis. Those associated with Jupiter were the first to be discovered.<ref name=Nicholson1961/>

E. E. Barnard made the first recorded observation of a trojan, 12126 Chersidamas (identified as A904 RD at the time), in 1904, but neither he nor others appreciated its significance at the time.<ref name=Barnard1904>{{cite web|date=1 October 1999|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|access-date=20 January 2009|archive-url=https://web.archive.org/web/20081114082429/http://www.cfa.harvard.edu/iau/pressinfo/TheFirstTrojanObs.html|archive-date=14 November 2008|url-status=live}}</ref> Barnard believed he had seen the recently discovered Saturnian satellite Phoebe, which was only two arc-minutes away in the sky at the time, or possibly an asteroid. The object's identity was not understood until its orbit was calculated in 1999.<ref name=Barnard1904/>

The first accepted discovery of a trojan occurred in February 1906, when astronomer Max Wolf of Heidelberg-Königstuhl State Observatory discovered an asteroid at the {{L4|nolink=yes}} Lagrangian point of the Sun–Jupiter system, later named 588 Achilles.<ref name=Nicholson1961/> In 1906–1907 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|nolink=yes}} swarm ("ahead" of the planet in its orbit), whereas Patroclus was the first asteroid known to reside at the {{L5|nolink=yes}} Lagrangian point ("behind" the planet).<ref name=Einarsson1913/> By 1938, 11 Jupiter trojans had been detected.<ref name=Wyse1938/> This number increased to 14 only in 1961.<ref name=Nicholson1961/> As instruments improved, the rate of discovery grew rapidly: by January 2000, a total of 257 had been discovered;<ref name=Jewitt2000/> by May 2003, the number had grown to 1,600.<ref name=Fernandes2003/> {{As of|2026|February}} there are 9,738 known Jupiter trojans at {{L4|nolink=yes}} and 5,931 at {{L5|nolink=yes}}.<ref name="MPC-count-by-camp" />

== Nomenclature == The custom of naming all asteroids in Jupiter's {{L4|nolink=yes}} and {{L5|nolink=yes}} 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 leading ({{L4|nolink=yes}}) orbit are named after Greek heroes (the "Greek node or camp" or "Achilles group"), and those at the trailing ({{L5|nolink=yes}}) orbit are named after the heroes of Troy (the "Trojan node or camp").<ref name=Nicholson1961/> The asteroids 617 Patroclus and 624 Hektor were named before the Greece/Troy rule was devised, resulting in a "Greek spy", Patroclus, in the Trojan node and a "Trojan spy", Hector, in the Greek node.<ref name=Wyse1938/><ref name="spies">{{cite web|title=Trojan Asteroids|url=http://astronomy.swin.edu.au/cosmos/T/Trojan+Asteroids|website=Cosmos|publisher=Swinburne University of Technology|access-date=13 June 2017|archive-url=https://web.archive.org/web/20170623182748/http://astronomy.swin.edu.au/cosmos/T/Trojan+Asteroids|archive-date=23 June 2017|url-status=live}}</ref>

In 2018, at its 30th General Assembly in Vienna, the International Astronomical Union amended the naming convention for Jupiter trojans, allowing for asteroids with ''H'' larger than 12 (that is, a mean diameter smaller than approximately 22 kilometers, for an assumed albedo of 0.057) to be named after Olympic or Paralympic athletes, because there are now far more known Jupiter trojans than available names of Greek and Trojan warriors that fought in the Trojan war.<ref>{{Cite web|title=MPEC 2020-T164|url=https://minorplanetcenter.net/mpec/K20/K20TG4.html|date=15 October 2020|access-date=24 June 2025|website=minorplanetcenter.net}}</ref> As of 4 May 2026, 38 Jupiter trojans have been named after athletes.<ref>{{Cite web|url=https://minorplanetcenter.net/iau/lists/JupiterTrojans.html|title=List Of Jupiter Trojans|website=minorplanetcenter.net|date=25 February 2026|access-date=7 May 2026|publisher=International Astronomical Union}}</ref><ref>{{Cite web|title=WGSBN Bulletins|url=https://www.wgsbn-iau.org/|website=wgsbn-iau.org|date=4 May 2026|access-date=7 May 2026|publisher=International Astronomical Union}}</ref> {{collapse top|List of Jupiter trojans named after Olympic or Paralympic athletes (as of 4 May 2026)}} {| class="wikitable sortable" style="width: 100%" ! width=150 | Minor planet ! Naming citation ! Camp ! width=90 | References |- | 17415 Czesławlang || Czesław Lang (b. 1955) is one of the most famous Polish road-racing cyclists and a prominent promoter of cycling in Poland. Since 1993, he has been the Director of the Tour de Pologne. Lang was also a silver medalist at the 1980 Summer Olympics, and a bronze and silver medalist at the Union Cycliste Internationale's Road World Championships in 1977 and 1979. || Trojan || {{WGSBNB|5|21|8}}{{·}}{{LoMP|17415|17415}} |- | 22010 Kuzmina || Anastasiya Kuzmina (b. 1984) is a Russian-born Slovak biathlete who has represented Slovakia since December 2008. She is the first biathlete to win gold medals in three consecutive Winter Olympics (2010 Vancouver, 2014 Sochi and 2018 Pyeongchang). || Greek || {{WGSBNB|1|6|4}}{{·}}{{LoMP|22010|22010}} |- | 24426 Belova || Elena Dmitriyevna Novikova-Belova (b. 1947) is a retired fencer from Belarus who became the first woman to win four gold medals during five Olympics from 1968 through 1980. In 2007 she was awarded the Pierre de Coubertin medal by the International Olympic Committee. || Greek || {{WGSBNB|1|1|14}}{{·}}{{LoMP|24426|24426}} |- | 25937 Malysz || Adam Małysz (b. 1977) is a Polish ski jumper who won multiple medals at the Olympic games in Salt Lake City (2002) and Vancouver (2010). He is also a four-time winner at the World Championships and the World Cup, and popularized ski jumping in Poland. || Greek || {{WGSBNB|1|11|6}}{{·}}{{LoMP|25937|25937}} |- | 25938 Stoch || Kamil Stoch (b. 1987), is a Polish ski jumper, who has won three gold medals at two Olympics (2014 and 2018) and multiple medals at World Championships (2013, 2017 and 2019). He is also a three-time winner of the 4-Hills-Tournament. || Greek || {{WGSBNB|1|11|7}}{{·}}{{LoMP|25938|25938}} |- | 28958 Binns || Hilda May (Torok) Binns (b. 1945) is a retired multi-sport athlete who won Canada’s first Paralympic gold medal in Tel Aviv in 1968. She won a total of six medals in two Paralympics and many medals and honors in other national and international competitions. || Greek || {{WGSBNB|1|1|16}}{{·}}{{LoMP|28958|28958}} |- | 39285 Kipkeino || Kipchoge Keino (b. 1940) won the 1500-m event at the 1968 Olympics by a record-setting margin of 20 meters. His running career spanned 1962 to 1973. After retiring, he and his wife, Phyllis, worked to educate and care for orphans in Kenya. In 2016 he was awarded the first Olympic Laurel for education, culture, development and peace through sport. || Greek || {{WGSBNB|1|1|17}}{{·}}{{LoMP|39285|39285}} |- | 39795 Marson || Roberto Marson (1944–2011) was a multi-sport athlete who competed in four Paralympics from 1964 to 1976 winning a total of 26 medals. He was named Outstanding Athlete at the 1968 games after winning ten gold medals. He was added to the International Paralympian Hall of Fame in 2012. || Greek || {{WGSBNB|1|1|17}}{{·}}{{LoMP|39795|39795}} |- | 43212 Katosawao || Sawao Katō (b. 1946) competed in three Olympics from 1968 to 1976 winning twelve medals in gymnastics including eight gold medals, the most for any Japanese Olympic athlete. He was inducted into the International Gymnastics Hall of Fame in 2001. || Greek || {{WGSBNB|1|1|17}}{{·}}{{LoMP|43212|43212}} |- | 43436 Ansschut || Johanna “Ans” Boekema-Schut (b. 1944) set an Olympic record in speed skating at the 1968 Olympics as a member of the Netherlands Olympic team. She set several world records in international events the following year. She retired from competition in 1971. || Greek || {{WGSBNB|1|1|18}}{{·}}{{LoMP|43436|43436}} |- | 57915 Mahuchikh || Yaroslava Mahuchikh (b. 2001) is a Ukrainian high jumper and Olympic champion. After winning bronze at the 2020 Olympics, she claimed gold in 2024. Earlier that year, Yaroslava set a women’s high jump world record of 2.10 meters, surpassing a mark that had stood for 36 years. || Greek || {{WGSBNB|5|19|8}}{{·}}{{LoMP|57915|57915}} |- | 111571 Bebevio || Beatrice Maria Adelaide Marzia Vio (b. 1997), known as Bebe Vio, is an Italian wheelchair fencer. She won at the 2014 and 2016 European championships, 2015 and 2017 World championships, and 2016 and 2020 Paralympic games in the foil B category. Her enthusiasm and joy for life is an extraordinary example of resilience and rebirth after a difficult illness. || Greek || {{WGSBNB|1|8|7}}{{·}}{{LoMP|111571|111571}} |- | 117385 Maughan || Margaret Gardner Maughan (1928–2020) was a British Paralympian. In 1960, she won her nation’s first Paralympic gold medal. Margaret lit the cauldron at the 2012 Paralympic Games in London. || Trojan || {{WGSBNB|6|7|8}}{{·}}{{LoMP|117385|117385}} |- | 171424 Rudyfernández || Rodolfo ‘Rudy’ Fernández Farrés (b. 1985) is a Spanish basketball player for Real Madrid. He is a two-time world champion (2006, 2019), a four-time continental champion (2009, 2011, 2015, 2022), and a triple Olympic runner-up (silver in 2008 and 2012, bronze in 2016). He has played in the NBA for Portland and Denver. || Greek || {{WGSBNB|3|5|14}}{{·}}{{LoMP|171424|171424}} |- | 247341 Shaulladany || Shaul Paul Ladany (b. 1936) competed as a racewalker for Israel in the 1968 and 1972 Olympics and set the world record for the 50-mile walk in April 1972. He survived the Holocaust and, later, the massacre at the Munich Olympics. In 2007 he was awarded the Pierre de Coubertin Medal and was inducted into the International Jewish Sports Hall of Fame in 2012. || Trojan || {{WGSBNB|3|5|14}}{{·}}{{LoMP|247341|247341}} |- | 264068 Gudzinevičiūtė || Daina Gudzinevičiūtė (b. 1965) is an Olympic shooting champion from Lithuania, president of the National Olympic Committee, and a member of the International Olympic Committee. She won the trap-shooting gold medal at the 2000 Summer Olympics in Sydney. Gudzinevičiūtė is respected for her contribution to the development of sport in Lithuania. || Greek || {{WGSBNB|6|7|9}}{{·}}{{LoMP|264068|264068}} |- | 264119 Georgeorton || George Washington Orton (1873–1958) was a middle- and long-distance runner. In 1900, he became the first Canadian to win a medal at an Olympic Games. || Greek || {{WGSBNB|2|7|13}}{{·}}{{LoMP|264119|264119}} |- | 306001 Joanllaneras || Joan Llaneras Roselló (b. 1969) is a Spanish cyclist who was a two-time Olympic champion and seven-time world champion. He participated in four Olympic Games between 1996 and 2008, winning four medals in total: gold in Sydney 2000; silver in Athens 2004; and gold and silver in Beijing 2008. || Greek || {{JPL|306001}}{{·}}{{LoMP|306001|306001}} |- | 310025 Marcuscooper || Marcus Cooper Walz (b. 1994) is an English-born Spanish athlete who competes in flat-water canoeing. He has participated in three Olympic Games, obtaining three medals: gold in Rio de Janeiro 2016 (K1 1000 m event); silver in Tokyo 2020; and bronze in Paris 2024 (K4 500 m event). || Greek || {{WGSBNB|5|4|34}}{{·}}{{LoMP|310025|310025}} |- | 312001 Siobhánhaughey || Siobhán Haughey (b. 1997) is a prominent Hong Kong swimmer specializing in freestyle and individual medley events. She has held 99 Hong Kong records and 23 Asian records in her career. Siobhán was the first Hong Kong athlete to win four Olympic medals. || Greek || {{WGSBNB|5|3|16}}{{·}}{{LoMP|312001|312001}} |- | 312627 Brigitteyagüe || Brigitte Yagüe Enrique (b. 1981) is a Spanish athlete who competed in taekwondo and won the silver medal at the 2012 London Olympics. She was world champion in 2003, 2007 and 2009, and European champion in 1998, 2002, 2004 and 2008. Brigitte was awarded the Gold Medal of the Royal Order of Sporting Merit in 2010. || Greek || {{WGSBNB|5|4|34}}{{·}}{{LoMP|312627|312627}} |- | 315941 Elenagómez || Elena Gómez Servera (b. 1985) is the only Spanish artistic gymnast to have been world champion, winning the gold floor medal at the 2002 World Championships in Hungary. She has won 11 medals in official international competitions, a record for a Spanish female gymnast. She was a member of the Spanish team that finished fifth at the 2004 Athens Olympics. || Greek || {{WGSBNB|5|4|34}}{{·}}{{LoMP|315941|315941}} |- | 352655 Alekna || Mykolas Alekna (b. 2002) is a Lithuanian athlete who specializes in the discus throw. He won the silver medal at the Paris Olympic Games in 2024 and is the current men’s world record holder of the event with 75.56 meters. || Greek || {{WGSBNB|6|3|13}}{{·}}{{LoMP|352655|352655}} |- | 353194 Meilutytė || Rūta Meilutytė (b. 1997) is a Lithuanian swimmer and Olympic champion. She won the gold medal in the 100-m breaststroke at the 2012 London Olympics. Meilutytė has also achieved multiple World and European Championship titles, becoming one of the most successful Lithuanian swimmers in history. || Greek || {{WGSBNB|6|7|10}}{{·}}{{LoMP|353194|353194}} |- | 542246 Kulcsár || Győző Kulcsár (1940–2018) was a Hungarian fencer who won four gold and two bronze medals in épée at four Olympic Games between 1964 and 1976. He also won three world titles with the Hungarian team. After retiring from competitions he worked as a fencing coach, his trainees include two Olympic champions. || Greek || {{WGSBNB|1|12|11}}{{·}}{{LoMP|542246|542246}} |- | 545564 Sabonis || Arvydas Sabonis (b. 1964) is a retired Lithuanian professional basketball player and businessman. Sabonis won a gold medal at the 1988 Summer Olympics, and bronze medals at the 1992 and 1996 Olympic Games. || Trojan || {{WGSBNB|2|8|11}}{{·}}{{LoMP|545564|545564}} |- | 546275 Kozák || Danuta Kozák (b. 1987) is a Hungarian sprint canoeist, who won six gold, one silver and one bronze medals at four Olympic Games between 2008 and 2021. He also won fifteen gold medals at World Championships, and seventeen gold medals at European Championships. || Greek || {{WGSBNB|2|2|9}}{{·}}{{LoMP|546275|546275}} |- | 546286 Fuchsjenő || Jenő Fuchs (1882–1955) was a four-time Hungarian Olympic champion saber fencer. He won both the individual and team events at the 1908 and 1912 Olympics. Jenő studied law at the University of Budapest, defended a Ph.D. in 1911, and became a lawyer. In 1982 he was inducted into the International Jewish Sports Hall of Fame. || Greek || {{WGSBNB|5|23|11}}{{·}}{{LoMP|546286|546286}} |- | 546396 Szilágyiáron || Áron Szilágyi (b. 1990) is a Hungarian Olympic, European and world champion saber fencer. Since 2017, he has been a goodwill ambassador of the New Europe Foundation. In 2021, he accepted the invitation to become Social Chairman of the Forum for the Protection of Interests of Hungarian Elite Athletes. || Greek || {{WGSBNB|5|23|11}}{{·}}{{LoMP|546396|546396}} |- | 567329 Zinaida || Zinaida Voronina, born Zinaida Borisovna Druzhinina (1947–2001), was an artistic gymnast who became the first Olympic champion in the history of Mari sports. At the 1968 Olympics in Mexico City, she won gold, silver and bronze medals. || Greek || {{JPL|567329}}{{·}}{{LoMP|567329|567329}} |- | 573759 Rocheva || Nina Rocheva, born Nina Petrovna Selyunina (1948–2022), was a cross-country skier who became the first world champion in the history of Mari sports. She won a silver medal in the 4 × 5 km relay at the 1980 Winter Olympics in Lake Placid, New York. || Greek || {{WGSBNB|3|3|17}}{{·}}{{LoMP|573759|573759}} |- | 595901 Lilybeaurepaire || Lillian de Beaurepaire (1892–1979) was an Australian Olympic swimmer and diver. She competed in the 1920 Olympics at Antwerp. She served as a lifesaver at Lorne Beach, Victoria, and is credited with saving 50 people from drowning, including a widely publicized heroic save of three men from rough surf in 1933. || Greek || {{WGSBNB|6|6|12}}{{·}}{{LoMP|595901|595901}} |- | 601227 Ammann || Simon Ammann (b. 1981) is a Swiss ski jumper. He is one of the most successful athletes in the history of his sport, having won four individual Winter Olympic gold medals in 2002 and 2010. His other achievements include winning the 2007 Ski Jumping World Championships and the 2010 Ski Flying World Championships. || Greek || {{WGSBNB|4|1|10}}{{·}}{{LoMP|601227|601227}} |- | 631626 Benedektibor || Tibor Benedek (1972–2020) was a Hungarian Olympic, European and World champion water polo player. He was captain of the men's national water polo team from 2013 to 2016, and was professional director of the UVSE Water Polo Sports Association from 2017 to 2020. Tibor is a member of the International Swimming Hall of Fame as part of Team Hungary 2000-2008. || Greek || {{WGSBNB|5|15|21}}{{·}}{{LoMP|631626|631626}} |- | 724932 Pozniakas || Danas Pozniakas (1939–2005) was a Lithuanian heavyweight boxer and Olympic champion. He won the gold medal at the 1968 Mexico City Summer Olympics. Pozniakas was also a two-time European champion and a prominent figure in international boxing during the 1960s. Pozniakas is remembered as one of Lithuania’s greatest boxers of all time. || Greek || {{WGSBNB|6|7|11}}{{·}}{{LoMP|724932|724932}} |- | 765015 Marčiulionis || Raimondas Šarūnas Marčiulionis (b. 1964) is a Lithuanian former professional basketball player. Widely considered one of the greatest international players, he was one of the first Europeans to become a regular in the National Basketball Association. He won a gold medal at the 1988 Olympics, and bronze medals at the 1992 and 1996 Olympic Games. || Trojan || {{WGSBNB|6|3|14}}{{·}}{{LoMP|765015|765015}} |- | 811110 Ubartas || Romas Ubartas (b. 1960) is a Lithuanian discus thrower and Olympic champion. He won the gold medal at the 1992 Barcelona Summer Olympics, earning Lithuania’s first-ever Olympic gold medal. Ubartas also won a silver medal at the 1988 Seoul Summer Olympics and became European champion in 1986. His personal best throw was 70.06 meters. || Greek || {{WGSBNB|6|7|12}}{{·}}{{LoMP|811110|811110}} |- | 826856 Commodorecochran || Commodore Shelton Cochran (1902–1969) was the first athlete from Mississippi to win an Olympic gold medal, running the first leg of the USA's 4×400-m relay team at the 1924 Paris games. Cochran attended Mississippi State University, in Starkville, where this asteroid was discovered. || Greek || {{WGSBNB|5|25|9}}{{·}}{{LoMP|826856|826856}} |} {{collapse bottom}}

== Numbers and mass == [[File:Lagrange points.jpg|thumb|right|A gravitational potential contour plot showing Earth's Lagrangian points; {{L4|nolink=yes}} and {{L5|nolink=yes}} are ahead (above) and behind (below) the planet, respectively. Jupiter's Lagrangian points are similarly situated in its much larger orbit.]]

Estimates of the total number of Jupiter trojans are based on deep surveys of limited areas of the sky.<ref name=Yoshida2005/> The {{L4|nolink=yes}} swarm is believed to hold between 160,000 and 240,000 asteroids with diameters larger than 2 km and about 600,000 with diameters larger than 1 km.<ref name=Yoshida2005/><ref name=Jewitt2000/> If the {{L5|nolink=yes}} swarm contains a comparable number of objects, there are more than {{Nowrap|1 million}} Jupiter trojans 1 km in size or larger. These numbers are similar to that of comparable asteroids in the asteroid belt.<ref name=Yoshida2005/> As of 2003, the population was probably complete for the objects brighter than absolute magnitude 9.0.<ref name=Fernandes2003/>{{needs update inline|date=May 2026|reason=This figure is outdated by more than 20 years.}} The total mass of the Jupiter trojans is estimated at 0.0001 of the mass of Earth or one-fifth of the mass of the asteroid belt.<ref name=Jewitt2000/>

Two more recent studies (published in 2008 and 2009) indicate that the above numbers may overestimate the number of Jupiter trojans by several-fold. This overestimate is caused by (1) the assumption that all Jupiter trojans have a low albedo of about 0.04, whereas small bodies may have an average albedo as high as 0.12;<ref name=Fernandes2009/> (2) an incorrect assumption about the distribution of Jupiter trojans in the sky.<ref name=Nakamura2008/> According to the new estimates, the total number of Jupiter trojans with a diameter larger than 2 km is {{nowrap|6,300 ± 1,000}} and {{nowrap|3,400 ± 500}} in the L4 and L5 swarms, respectively.<ref name=Nakamura2008/> These numbers would be reduced by a factor of 2 if small Jupiter trojans are more reflective than large ones.<ref name=Fernandes2009/>

The number of Jupiter trojans observed in the {{L4|nolink=yes}} swarm is slightly larger than that observed in {{L5|nolink=yes}}. Because the brightest Jupiter trojans show little variation in numbers between the two populations, this disparity is probably due to observational bias.<ref name=Jewitt2004/>{{dubious|date=May 2026|reason=This is per a study published in 2004, which was likely outdated already by 2008/2009, compare the previous paragraph.}} Some models indicate that the {{L4|nolink=yes}} swarm may be slightly more stable than the {{L5|nolink=yes}} swarm.<ref name=Marzari2002/>

The largest Jupiter trojan is 624 Hektor, which has a mean diameter of 203 ± 3.6 km.<ref name=Fernandes2003/> There are few large Jupiter trojans in comparison to the overall population. With decreasing size, the number of Jupiter trojans grows very quickly down to 84 km, much more so than in the asteroid belt. A diameter of 84 km corresponds to an absolute magnitude of 9.5, assuming an albedo of 0.04. Within the 4.4–40 km range the Jupiter trojans' size distribution resembles that of the main-belt asteroids. Nothing is known about the masses of the smaller Jupiter trojans.<ref name=Marzari2002/> The size distribution suggests that the smaller Trojans may be the products of collisions by larger Jupiter trojans.<ref name=Jewitt2004/>

== Orbits == thumb|Animation of the orbit of 624 Hektor (blue), set against the orbit of Jupiter (outer red ellipse)

Jupiter trojans have orbits with radii between 5.05 and 5.35 AU (the mean semi-major axis is 5.2 ± 0.15 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 AU.<ref name=Jewitt2000/> The width of the swarms approximately equals two Hill's radii, which in the case of Jupiter amounts to about 0.6 AU.<ref name=Marzari2002/> Many of Jupiter trojans have large orbital inclinations relative to Jupiter's orbital plane—up to 40°.<ref name=Jewitt2000/>

Jupiter trojans do not maintain a fixed separation from Jupiter. They slowly librate around their respective equilibrium points, periodically moving closer to Jupiter or farther from it.<ref name=Marzari2002/> Jupiter trojans generally follow paths called tadpole orbits 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 show that Jupiter trojans can follow even more complicated trajectories when moving from one Lagrangian point to another—these are called horseshoe orbits (currently no Jupiter Trojan with such an orbit is known, though one is known for Neptune).<ref name=Marzari2002/>

=== Dynamical families and binaries === Discerning dynamical families within the Jupiter trojan population is more difficult than it is in the asteroid belt, because the Jupiter trojans are locked within a far narrower range of possible positions. This means that clusters tend to overlap and merge with the overall swarm. By 2003 roughly a dozen dynamical families were identified. Jupiter-trojan families are much smaller in size than families in the asteroid belt; the largest identified family, the Menelaus group, consists of only eight members.<ref name=Jewitt2004/>

In 2001, 617 Patroclus was the first Jupiter trojan to be identified as a binary asteroid.<ref name="Merline">{{cite web|last=Merline|first=W. J.|date=2001|url=http://cbat.eps.harvard.edu/iauc/07700/07741.html#Item2|title=IAUC 7741: 2001fc; S/2001 (617) 1; C/2001 T1, C/2001 T2|access-date=25 October 2010|archive-url=https://web.archive.org/web/20110719210034/http://cbat.eps.harvard.edu/iauc/07700/07741.html#Item2|archive-date=19 July 2011|url-status=live}}</ref> The binary's orbit is extremely close, at 650 km, compared to 35,000 km for the primary's Hill sphere.<ref name=Marchis2006/> The largest Jupiter trojan—624 Hektor— is probably a contact binary with a moonlet.<ref name=Jewitt2004/><ref name=IAUC8732>{{cite web|url=http://cbat.eps.harvard.edu/iauc/08700/08732.html#Item1|title=IAUC 8732: S/2006 (624) 1|access-date=23 July 2006|archive-url=https://web.archive.org/web/20110719210046/http://cbat.eps.harvard.edu/iauc/08700/08732.html#Item1|archive-date=19 July 2011|url-status=live}} (Satellite Discovery)</ref><ref name=Lacerda2007/>

== Physical properties == [[File:624Hektor-LB1-mag15.jpg|thumb|right|Trojan 624 Hektor (indicated) is similar in brightness to dwarf planet Pluto.]]

Jupiter trojans are dark bodies of irregular shape. Their geometric albedos generally vary between 3 and 10%.<ref name=Fernandes2003/> The average value is 0.056 ± 0.003 for the objects larger than 57 km,<ref name=Jewitt2004/> and 0.121 ± 0.003 (R-band) for those smaller than 25 km.<ref name=Fernandes2009/> The asteroid 4709 Ennomos has the highest albedo (0.18) of all known Jupiter trojans.<ref name=Fernandes2003/> Little is known about the masses, chemical composition, rotation or other physical properties of the Jupiter trojans.<ref name=Jewitt2004/>

=== Rotation === The rotational properties of Jupiter trojans are not well known. Analysis of the rotational light curves of 72 Jupiter trojans gave an average rotational period of about 11.2 hours, whereas the average period of the control sample of asteroids in the asteroid belt was 10.6 hours.<ref name=Barucci2002/> The distribution of the rotational periods of Jupiter trojans appeared to be well approximated by a Maxwellian function,<ref group="Note">The Maxwellian function is <math>F=\begin{smallmatrix}\frac{1}{\sqrt{2\pi}\sigma}P^2\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 dispersion of periods.</ref> whereas the distribution for main-belt asteroids was found to be non-Maxwellian, with a deficit of periods in the range 8–10 hours.<ref name=Barucci2002/> The Maxwellian distribution of the rotational periods of Jupiter trojans may indicate that they have undergone a stronger collisional evolution compared to the asteroid belt.<ref name=Barucci2002/>

In 2008 a team from Calvin College examined the light curves of a debiased sample of ten Jupiter trojans, and found a median spin period of 18.9 hours. This value was significantly higher than that for main-belt asteroids of similar size (11.5 hours). The difference could mean that the Jupiter trojans possess a lower average density, which may imply that they formed in the Kuiper belt (see below).<ref>{{cite journal|last1=Molnar|first1=Lawrence A.|last2=Haegert|first2=Melissa J.|last3=Hoogeboom|first3=Kathleen M.|date=April 2008|title=Lightcurve Analysis of an Unbiased Sample of Trojan Asteroids|journal=The Minor Planet Bulletin|publisher=Association of Lunar and Planetary Observers|volume=35|issue=2|pages=82–84|oclc=85447686|bibcode=2008MPBu...35...82M}}</ref>

=== Composition === Spectroscopically, the Jupiter trojans mostly are D-type asteroids, which predominate in the outer regions of the asteroid belt.<ref name=Jewitt2004/> A small number are classified as P or C-type asteroids.<ref name=Barucci2002/> Their spectra are red (meaning that they reflect more 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|2007|lc=on}}. 4709 Ennomos has an albedo slightly higher than the Jupiter-trojan average, which may indicate the presence of water ice. Some other Jupiter Trojans, such as 911 Agamemnon and 617 Patroclus, have shown very weak absorptions at 1.7 and 2.3 μm, which might indicate the presence of organics.<ref>{{cite journal|title=Spectroscopic Search for Water Ice on Jovian Trojan Asteroids|last1=Yang|first1=Bin|last2=Jewitt|first2=David|date=2007|journal=The Astronomical Journal|volume=134|issue=1|pages=223–228|doi=10.1086/518368|url=http://www.iop.org/EJ/abstract/1538-3881/134/1/223/|access-date=19 January 2009|bibcode=2007AJ....134..223Y|doi-access=free}}</ref> The Jupiter trojans' spectra are similar to those of the irregular moons of Jupiter and, to a certain extent, comet nuclei, though Jupiter trojans are spectrally very different from the redder Kuiper belt objects.<ref name=Yoshida2005/><ref name=Jewitt2004/> A Jupiter 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 silicates.<ref name=Barucci2002/> The composition of the Jupiter 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.|author2=Fornasier, S.|author3=Barucci, M. A.|journal=Icarus|volume=183|issue=2|date=August 2006|pages=420–434|doi=10.1016/j.icarus.2006.02.012|bibcode=2006Icar..183..420D|display-authors=etal}}</ref>

A team from the Keck Observatory in Hawaii announced in 2006 that it had measured the density of the binary Jupiter trojan 617 Patroclus as being less than that of water ice (0.8 g/cm3), suggesting that the pair, and possibly many other Trojan objects, more closely resemble comets or Kuiper belt objects in composition—water ice with a layer of dust—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 g/cm3) is significantly higher than that of 617 Patroclus.<ref name=Lacerda2007/> Such a difference in densities suggests 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 Jupiter trojans. The first suggests that the Jupiter trojans formed in the same part of the Solar System as Jupiter and entered their orbits while it 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 planetesimals 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—about 50% of all remaining planetesimals were trapped. This hypothesis has two major problems: the number of trapped bodies exceeds the observed population of Jupiter trojans by four orders of magnitude, and the present Jupiter trojan asteroids have larger orbital inclinations than are predicted by the capture model.<ref name=Marzari2002/> Simulations of this scenario show that such a mode of formation also would inhibit the creation of similar trojans for Saturn, and this has been borne out by observation: to date no trojans have been found near Saturn.<ref>{{cite journal|title=The growth of Jupiter and Saturn and the capture of Trojans |last1=Marzari|first1=F. |last2=Scholl|first2=H. |journal=Astronomy and Astrophysics|volume=339|pages=278–285|date=1998|bibcode=1998A&A...339..278M}}</ref> In a variation of this theory Jupiter captures trojans during its initial growth then migrates as it continues to grow. During Jupiter's migration the orbits of objects in horseshoe orbits are distorted causing the L4 side of these orbits to be over occupied. As a result, an excess of trojans is trapped on the L4 side when the horseshoe orbits shift to tadpole orbits as Jupiter grows. This model also leaves the Jupiter trojan population 3–4 orders of magnitude too large.<ref name="Pirani_etal_2019">{{cite journal |last1=Pirani |first1=S. |last2=Johansen |first2=A. |last3=Bitsch |first3=B. |last4=Mustill |first4=A. J. |last5=Turrini |first5=D. |title=Consequences of planetary migration on the minor bodies of the early solar system |journal=Astronomy & Astrophysics |date=2019 |volume=623 |page=A169 |doi=10.1051/0004-6361/201833713 |arxiv=1902.04591 |bibcode=2019A&A...623A.169P |s2cid=119546182 }}</ref>

The second theory proposes that the Jupiter trojans were captured during the migration of the giant planets described in the Nice model. In the Nice model the orbits of the giant planets became unstable {{Nowrap|500–600 million}} years after the Solar System's formation when Jupiter and Saturn crossed their 1:2 mean-motion resonance. Encounters between planets resulted in Uranus and Neptune being scattered outward into the primordial Kuiper belt, disrupting it and throwing millions of objects inward.<ref name=Levison2007/> When Jupiter and Saturn were near their 1:2 resonance the orbits of pre-existing Jupiter trojans became unstable during a secondary resonance with Jupiter and Saturn. This occurred when the period of the trojans' libration about their Lagrangian point had a 3:1 ratio to the period at which the position where Jupiter passes Saturn circulated relative to its perihelion. This process was also reversible allowing a fraction of the numerous objects scattered inward by Uranus and Neptune to enter this region and be captured as Jupiter's and Saturn's orbits separated. These new trojans had a wide range of inclinations, the result of multiple encounters with the giant planets before being captured.<ref name="Morbidelli">{{cite journal|last=Morbidelli|first=A.|author2=Levison, H. F.|author3=Tsiganis, K.|author4=Gomes, R.|date=26 May 2005|title=Chaotic capture of Jupiter's Trojan asteroids in the early Solar System|journal=Nature|volume=435|issue=7041|pages=462–465|oclc=112222497|url=http://www.oca.eu/michel/PubliGroupe/MorbyNature2005.pdf|doi=10.1038/nature03540|pmid=15917801|bibcode=2005Natur.435..462M|s2cid=4373366 |access-date=19 January 2009|archive-url=https://web.archive.org/web/20090731120551/http://www.oca.eu/michel/PubliGroupe/MorbyNature2005.pdf|archive-date=31 July 2009|url-status=dead}}</ref> This process can also occur later when Jupiter and Saturn cross weaker resonances.<ref name=Nesvorny_2013>{{cite journal|last=Nesvorný|first=David|author2=Vokrouhlický, David |author3=Morbidelli, Alessandro |title=Capture of Trojans by Jumping Jupiter|journal=The Astrophysical Journal|date=2013|volume=768|issue=1|page=45|doi=10.1088/0004-637X/768/1/45|arxiv=1303.2900|bibcode=2013ApJ...768...45N|s2cid=54198242 }}</ref>

In a revised version of the Nice model Jupiter trojans are captured when Jupiter encounters an ice giant during the instability. In this version of the Nice model one of the ice giants (Uranus, Neptune, or a lost fifth planet) is scattered inward onto a Jupiter-crossing orbit and is scattered outward by Jupiter causing the orbits of Jupiter and Saturn to quickly separate. When Jupiter's semi-major axis jumps during these encounters existing Jupiter trojans can escape and new objects with semi-major axes similar to Jupiter's new semi-major axis are captured. Following its last encounter the ice giant can pass through one of the libration points and perturb their orbits leaving this libration point depleted relative to the other. After the encounters end some of these Jupiter trojans are lost and others captured when Jupiter and Saturn are near weak mean motion resonances such as the 3:7 resonance via the mechanism of the original Nice model.<ref name="Nesvorny_2013"/>

The long-term future of the Jupiter trojans is open to question, because multiple weak resonances with Jupiter and Saturn cause them to behave chaotically over time.<ref name=Robutal2005/> Collisional shattering slowly depletes the Jupiter trojan population as fragments are ejected. Ejected Jupiter trojans could become temporary satellites of Jupiter or Jupiter-family comets.<ref name=Jewitt2004/> Simulations show that the orbits of up to 17% of Jupiter trojans are unstable over the age of the Solar System.<ref>{{cite journal|title=Chaotic Diffusion And Effective Stability of Jupiter trojans |author=Kleomenis Tsiganis |author2=Harry Varvoglis |author3=Rudolf Dvorak |publisher=Springer|journal=Celestial Mechanics and Dynamical Astronomy|volume=92|date=April 2005|doi=10.1007/s10569-004-3975-7|pages=71–87|issue=1–3|bibcode = 2005CeMDA..92...71T |s2cid=123648472 }}</ref> Levison et al. believe that roughly 200 ejected Jupiter trojans greater than 1 km in diameter might be travelling 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. |author2=Shoemaker, Eugene M. |author3=Shoemaker, Carolyn S.|journal=Nature|volume=385|issue=6611|pages=42–44|date=1997|doi=10.1038/385042a0|bibcode = 1997Natur.385...42L |s2cid=4323757 }}</ref> Some of the escaped Jupiter trojans may become Jupiter-family comets as they approach the Sun and their surface ice begins evaporating.<ref name=Levison1997/>

== Exploration == On 4 January 2017 NASA announced that ''Lucy'' was selected as one of their next two Discovery Program missions.<ref>{{Cite news|url=https://www.nasa.gov/press-release/nasa-selects-two-missions-to-explore-the-early-solar-system/|title=NASA Selects Two Missions to Explore the Early Solar System|last=Northon|first=Karen|date=4 January 2017|newspaper=NASA|access-date=5 January 2017|archive-url=https://web.archive.org/web/20170105003614/https://www.nasa.gov/press-release/nasa-selects-two-missions-to-explore-the-early-solar-system/|archive-date=5 January 2017|url-status=live}}</ref> ''Lucy'' is set to explore seven<ref>{{cite web |title=Tour |url=http://lucy.swri.edu/mission/Tour.html |website=Lucy Mission Website |publisher=NASA |access-date=5 October 2021 |archive-date=8 September 2018 |archive-url=https://web.archive.org/web/20180908073839/http://lucy.swri.edu/mission/Tour.html |url-status=live }}</ref> Jupiter trojans. It was launched on October 16, 2021, and will arrive at the {{L4}} Trojan cloud in 2027 after two Earth gravity assists and a fly-by of a main-belt asteroid. It will then return to the vicinity of Earth for another gravity assist to take it to Jupiter's {{L5}} Trojan cloud where it will visit 617 Patroclus.<ref name="round 1">{{cite news |last1=Dreier |first1=Casey |last2=Lakdawalla |first2=Emily |url=http://www.planetary.org/blogs/casey-dreier/2015/09301336-discovery-downselect.html |title=NASA announces five Discovery proposals selected for further study |work=The Planetary Society |date=30 September 2015 |access-date=1 October 2015 |archive-url=https://web.archive.org/web/20151002190608/http://www.planetary.org/blogs/casey-dreier/2015/09301336-discovery-downselect.html |archive-date=2 October 2015 |url-status=live }}</ref>

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

== References == {{Reflist|30em|refs=

<ref name="MPC-Trojan-count">{{cite web |title=Trojan Minor Planets |publisher=Minor Planet Center |url=http://www.minorplanetcenter.org/iau/lists/Trojans.html |date=20 October 2025 |archive-url=https://web.archive.org/web/20251021131705/https://www.minorplanetcenter.org/iau/lists/Trojans.html |archive-date=21 October 2025 |url-status=live }}</ref>

<ref name="MPC-count-by-camp">{{cite web |title=List of Jupiter trojans |publisher=Minor Planet Center |url=http://www.minorplanetcenter.net/iau/lists/JupiterTrojans.html |date=25 February 2026 |archive-url=https://web.archive.org/web/20260305034255/https://www.minorplanetcenter.net/iau/lists/JupiterTrojans.html |archive-date=5 March 2026 |url-status=live }}</ref>

<ref name="Dotto2006">{{cite journal |title=The surface composition of Jupiter Trojans: Visible and near-infrared survey of dynamical families |journal=Icarus |pages=420–434 |year=2006 |volume=183 |issue=2 |last1=Dotto |first1=E |last2=Fornasier |first2=S |last3=Barucci |first3=M.A |last4=Licandr o|first4=J |last5=Boehnhardt |first5=H |last6=Hainaut |first6=O |last7=Marzari |first7=F |last8=De Bergh |first8=C |last9=De Luise |first9=F |doi=10.1016/j.icarus.2006.02.012|bibcode=2006Icar..183..420D}}</ref>

<ref name="Jewitt2000">{{cite journal |last=Jewitt |first=David C. |author2=Trujillo, Chadwick A. |author3=Luu, Jane X. |title=Population and size distribution of small Jovian Trojan asteroids |date=2000 |journal=The Astronomical Journal |volume=120 |issue=2 |pages=1140–7 |doi=10.1086/301453 |bibcode=2000AJ....120.1140J |arxiv=astro-ph/0004117|s2cid=119450236 }}</ref>

<ref name="Yoshida2005">{{cite journal |last=Yoshida |first=F. |author2=Nakamura, T |title=Size distribution of faint L4 Trojan asteroids |date=2005 |journal=The Astronomical Journal |volume=130 |issue=6 |pages=2900–11 |doi=10.1086/497571 |bibcode=2005AJ....130.2900Y|doi-access=free }}</ref>

<ref name="Wyse1938">{{cite journal |last=Wyse |first=A. B. | author-link=Arthur Bambridge Wyse |title=The Trojan group |date=1938 |journal=Astronomical Society of the Pacific Leaflets |volume=3 |issue=114 |pages=113–19 |bibcode=1938ASPL....3..113W}}</ref>

<ref name="Einarsson1913">{{cite journal |last=Einarsson |first=Sturla |title=The Minor Planets of the Trojan Group |date=1913 |journal=Publications of the Astronomical Society of the Pacific |volume=25 |issue=148 |pages=131–3 |bibcode=1913PASP...25..131E |doi=10.1086/122216|s2cid=122428016 }}</ref>

<ref name=Nakamura2008>{{cite journal |last1=Nakamura |first1=Tsuko |last2=Yoshida |first2=Fumi |title=A New Surface Density Model of Jovian Trojans around Triangular Libration Points |date=2008 |journal=Publications of the Astronomical Society of Japan |volume=60 |issue=2 |pages=293–296 |bibcode=2008PASJ...60..293N |doi=10.1093/pasj/60.2.293|doi-access=free }}</ref>

<ref name="Nicholson1961">{{cite journal |last=Nicholson |first=Seth B. |title=The Trojan asteroids |date=1961 |journal=Astronomical Society of the Pacific Leaflets |volume=8 |issue=381 |pages=239–46 |bibcode=1961ASPL....8..239N}}</ref>

<ref name="Marzari2002">{{cite book |last=Marzari |first=F. |author2=Scholl, H. |author3=Murray C. |author4=Lagerkvist C. |date=2002 |chapter=Origin and Evolution of Trojan Asteroids |title=Asteroids III |publisher=University of Arizona Press |pages=725–38 |location=Tucson, Arizona |chapter-url=http://www.lpi.usra.edu/books/AsteroidsIII/pdf/3007.pdf |access-date=17 January 2009 |archive-date=6 June 2011 |archive-url=https://web.archive.org/web/20110606010204/http://www.lpi.usra.edu/books/AsteroidsIII/pdf/3007.pdf |url-status=live }}</ref>

<ref name="Barucci2002">{{cite book |last=Barucci |first=M.A. |author2=Kruikshank, D.P. |author3=Mottola S. |author4=Lazzarin M. |date=2002 |chapter=Physical Properties of Trojan and Centaur Asteroids |title=Asteroids III |publisher=University of Arizona Press |pages=273–87 |location=Tucson, Arizona}}</ref>

<ref name="Levison2007">{{cite journal |first1=Harold F. |last1=Levison |first2=Alessandro |last2=Morbidelli |first3=Christa |last3=Van Laerhoven |title=Origin of the Structure of the Kuiper Belt during a Dynamical Instability in the Orbits of Uranus and Neptune |date=2007 |bibcode=2008Icar..196..258L |arxiv=0712.0553 |doi=10.1016/j.icarus.2007.11.035 |journal=Icarus |volume=196 |issue=1 |pages=258–273 |s2cid=7035885 |display-authors=etal}}</ref>

<ref name="Marchis2006">{{cite journal |last=Marchis |first=Franck |author2=Hestroffer, Daniel |author3=Descamps, Pascal |title=A low density of 0.8 g cm−3 for the Trojan binary asteroid 617 Patroclus |date=2006 |journal=Nature |volume=439 |issue=7076 |pages=565–567 |bibcode=2006Natur.439..565M |doi=10.1038/nature04350 |pmid=16452974 |arxiv=astro-ph/0602033 |s2cid=4416425 |display-authors=etal}}</ref>

<ref name="Fernandes2003">{{cite journal |last=Fernandes |first=Yanga R. |author2=Sheppard, Scott S. |author3=Jewitt, David C. |title=The albedo distribution of Jovian Trojan asteroids |date=2003 |journal=The Astronomical Journal |volume=126 |issue=3 |pages=1563–1574 |bibcode=2003AJ....126.1563F |doi=10.1086/377015|citeseerx=10.1.1.7.5611 |s2cid=15977388 }}</ref>

<ref name=Fernandes2009>{{cite journal |last1=Fernández |first1=Y. R. |last2=Jewitt |first2=D. |last3=Ziffer |first3=J. E. |title=Albedos of Small Jovian Trojans |journal=The Astronomical Journal |volume=138 |issue=1 |pages=240–250 |year=2009 |doi=10.1088/0004-6256/138/1/240 |bibcode=2009AJ....138..240F |arxiv=0906.1786|s2cid=5592793 }}</ref>

<ref name="Lacerda2007">{{cite journal |last=Lacerda |first=Pedro |author2=Jewitt, David C. |title=Densities of Solar System Objects from Their Rotational Light Curves |date=2007 |journal=The Astronomical Journal |volume=133 |issue=4 |pages=1393–1408 |doi=10.1086/511772 |bibcode=2007AJ....133.1393L |arxiv=astro-ph/0612237|s2cid=17735600 }}</ref>

<ref name="Jewitt2004">{{cite book |last1=Jewitt |first1=David C. |last2=Sheppard |first2=Scott |last3=Porco |first3=Carolyn C. |chapter=Jupiter's Outer Satellites and Trojans |title=Jupiter: The Planet, Satellites and Magnetosphere |date=2004 |publisher=Cambridge University Press |s2cid=53962019 |editor=Bagenal, Fran |editor2=Dowling, Timothy E. |editor3=McKinnon, William B. |chapter-url=https://pdfs.semanticscholar.org/5a3f/11d47003a555cd96499776edc3adfb47f5fd.pdf |access-date=30 April 2021 |archive-date=9 November 2019 |archive-url=https://web.archive.org/web/20191109164923/https://pdfs.semanticscholar.org/5a3f/11d47003a555cd96499776edc3adfb47f5fd.pdf |url-status=bot: unknown }}</ref>

<ref name="Robutal2005">{{cite journal |last=Robutal |first=P. |author2=Gabern, F. |author3=Jorba A. |title=The observed Trojans and the global dynamics around the lagrangian points of the sun–jupiter system |date=2005 |journal=Celestial Mechanics and Dynamical Astronomy |volume=92 |issue=1–3 |pages=53–69 |doi=10.1007/s10569-004-5976-y |url=http://www.cds.caltech.edu/~gabern/preprints/osterreich.pdf |bibcode=2005CeMDA..92...53R |s2cid=5759776 |url-status=dead |archive-url=https://web.archive.org/web/20090731062642/http://www.cds.caltech.edu/~gabern/preprints/osterreich.pdf |archive-date=31 July 2009 }}</ref>

}}

== External links == {{Commons category|Jupiter trojans}} * {{cite web |last=Sheppard |first=Scott |url=http://www.dtm.ciw.edu/users/sheppard/satellites/trojan.html |title=The Trojan Page}} * {{cite journal |last1=Lykawka |author2=Horner |title=The Capture of Trojan Asteroids by the Giant Planets During Planetary Migration |first1=P. S. |doi=10.1111/j.1365-2966.2010.16538.x |date=2010 |journal=Monthly Notices of the Royal Astronomical Society |volume=405 |issue=1383 |pages=1375–1383 |doi-access=free |arxiv=1003.2137 |bibcode=2010MNRAS.405.1375L|s2cid=54084401 }} * [http://www.jpl.nasa.gov/news/news.php?release=2012-322 NASA's WISE Colors in Unknowns on Jupiter Asteroids] (NASA 2012-322 : 15 October 2012) * {{YouTube |id=arvl5JQ6ll0 |title=NASA's New Discovery Missions: ''Psyche'' and ''Lucy''}} * [https://gravitysimulator.org/solar-system/jupiter-and-its-ten-largest-trojans 3D Gravity Simulation of the Ten Largest Jupiter Trojan Asteroids] {{Webarchive|url=https://web.archive.org/web/20200611221939/https://gravitysimulator.org/solar-system/jupiter-and-its-ten-largest-trojans/ |date=11 June 2020 }}

{{Asteroids}} {{Jupiter}} {{Small Solar System bodies}} {{Portal bar|Astronomy|Stars|Spaceflight|Outer space|Solar system}} {{featured article}}

Category:Jupiter trojans 5