Jupiter trojan

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 ', existing 60° ahead of the planet in its orbit, or ', 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.
The first Jupiter trojan discovered, 588 Achilles, was spotted in 1906 by German astronomer Max Wolf. More than 15,300 Jupiter trojans have been found. 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, approximately equal to the number of asteroids larger than 1 km in the asteroid belt. Like main-belt asteroids, Jupiter trojans form families.
, 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. The Jupiter trojans' densities vary from 0.8 to 2.5 g·cm⁻³. 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.
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. 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.

Observational history

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. The trapped body will librate slowly around the point of equilibrium in a tadpole or horseshoe orbit. These leading and trailing points are called the and Lagrange points. 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.
E. E. Barnard made the first recorded observation of a trojan, 12126 Chersidamas, in 1904, but neither he nor others appreciated its significance at the time. 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.
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 Lagrangian point of the Sun–Jupiter system, later named 588 Achilles. In 1906–1907 two more Jupiter trojans were found by fellow German astronomer August Kopff. Hektor, like Achilles, belonged to the swarm, whereas Patroclus was the first asteroid known to reside at the Lagrangian point. By 1938, 11 Jupiter trojans had been detected. This number increased to 14 only in 1961. As instruments improved, the rate of discovery grew rapidly: by January 2000, a total of 257 had been discovered; by May 2003, the number had grown to 1,600. there are 9,694 known Jupiter trojans at and 5,628 at.

Nomenclature

The custom of naming all asteroids in Jupiter's and points after famous heroes of the Trojan War was suggested by Johann Palisa of Vienna, who was the first to accurately calculate their orbits.
Asteroids in the leading orbit are named after Greek heroes, and those at the trailing orbit are named after the heroes of Troy. 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.
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 to be named after Olympic athletes, because there are now far more known Jupiter trojans than available names of Greek and Trojan warriors that fought in the Trojan war. As of June 2025, 24 Jupiter trojans have been named after athletes.

Minor planet	Naming citation	References
22010 Kuzmina	Anastasiya Kuzmina 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.
24426 Belova	Elena Dmitriyevna Novikova-Belova 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.
25937 Malysz	Adam Małysz is a Polish ski jumper who won multiple medals at the Olympic games in Salt Lake City and Vancouver. He is also a four-time winner at the World Championships and the World Cup, and popularized ski jumping in Poland.
25938 Stoch	Kamil Stoch, is a Polish ski jumper, who has won three gold medals at two Olympics and multiple medals at World Championships. He is also a three-time winner of the 4-Hills-Tournament.
28958 Binns	Hilda May Binns 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.
39285 Kipkeino	Kipchoge Keino 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.
39795 Marson	Roberto Marson 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.
43212 Katosawao	Sawao Katō 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.
43436 Ansschut	Johanna “Ans” Boekema-Schut 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.
111571 Bebevio	Beatrice Maria Adelaide Marzia Vio, 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.
171424 Rudyfernández	Rodolfo ‘Rudy’ Fernández Farrés is a Spanish basketball player for Real Madrid. He is a two-time world champion, a four-time continental champion, and a triple Olympic runner-up. He has played in the NBA for Portland and Denver.
247341 Shaulladany	Shaul Paul Ladany 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.
264119 Georgeorton	George Washington Orton was a middle- and long-distance runner. In 1900, he became the first Canadian to win a medal at an Olympic Games.
306001 Joanllaneras	Joan Llaneras Roselló 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.
310025 Marcuscooper	Marcus Cooper Walz 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 ; silver in Tokyo 2020; and bronze in Paris 2024.
312001 Siobhánhaughey	Siobhán Haughey 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.
312627 Brigitteyagüe	Brigitte Yagüe Enrique 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.
315941 Elenagómez	Elena Gómez Servera 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.
542246 Kulcsár	Győző Kulcsár 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.
545564 Sabonis	Arvydas Sabonis 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.
546275 Kozák	Danuta Kozák 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.
567329 Zinaida	Zinaida Voronina, born Zinaida Borisovna Druzhinina, 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.
573759 Rocheva	Nina Rocheva, born Nina Petrovna Selyunina, 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.
601227 Ammann	Simon Ammann 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.