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List of Jupiter trojans (Greek camp)
List of Jupiter trojans (Greek camp)
List of Jupiter trojans (Greek camp)
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The asteroids of the inner Solar System and Jupiter.
  Jupiter trojans
  Orbits of planets
  Sun 		  Hilda group
  Asteroid belt
  Near-Earth objects (some)

This is a list of Jupiter trojans that lie in the Greek camp, an elongated curved region around the leading Lagrangian point (L4), 60° ahead of Jupiter in its orbit.

All the asteroids at Jupiter's L4 point have names corresponding to participants on the Greek side of the Trojan War, except for 624 Hektor, which was named before this naming convention was instituted. Correspondingly, 617 Patroclus is a Greek-named asteroid at the "Trojan" (L5) Lagrangian point. In 2018, at its 30th General Assembly in Vienna, the International Astronomical Union amended this naming convention, allowing Jupiter trojans with an 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 athletes, as the number of known Jupiter trojans, currently more than 10,000, far exceeds the number of available names of heroes from the Trojan War in Greek mythology.[1][2][3]

Trojans in the Greek and Trojan camp are discovered mainly in turns, because they are separated by 120°, and for a period of time, one group of trojans will be behind the Sun, while the other will be visible.

Partial lists

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As of July 2024, there are 8799 known objects in the Greek camp, of which 5099 are numbered and listed in the following partial lists:[2]

Largest members

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This is a list of the largest 100+ Jupiter trojans of both the Greek and Trojan camps.

100+ largest Jupiter trojans
Largest Jupiter Trojans by survey(A)
(mean-diameter in kilometers; YoD: Year of Discovery)
Designation H WISE IRAS Akari Ln RP V–I YoD Ref
624 Hektor 7.2 225 233 230.99 L4 6.92 0.930 1907 list
617 Patroclus 8.19 140.362 140.92 140.85 L5 102.80 0.830 1906 list
911 Agamemnon 7.89 131.038 166.66 185.30 L4 6.59 0.980 1919 list
588 Achilles 8.67 130.099 135.47 133.22 L4 7.31 0.940 1906 list
3451 Mentor 8.4 126.288 116.30 117.91 L5 7.70 0.770 1984 list
3317 Paris 8.3 118.790 116.26 120.45 L5 7.09 0.950 1984 list
1867 Deiphobus 8.3 118.220 122.67 131.31 L5 58.66 0.930 1971 list
1172 Äneas 8.33 118.020 142.82 148.66 L5 8.71 0.950 1930 list
1437 Diomedes 8.3 117.786 164.31 172.60 L4 24.49 0.810 1937 list
1143 Odysseus 7.93 114.624 125.64 130.81 L4 10.11 0.860 1930 list
2241 Alcathous 8.64 113.682 114.63 118.87 L5 7.69 0.940 1979 list
659 Nestor 8.99 112.320 108.87 107.06 L4 15.98 0.790 1908 list
3793 Leonteus 8.7 112.046 86.26 87.58 L4 5.62 0.780 1985 list
3063 Makhaon 8.4 111.655 116.14 114.34 L4 8.64 0.830 1983 list
1583 Antilochus 8.6 108.842 101.62 111.69 L4 31.54 0.950 1950 list
884 Priamus 8.81 101.093 96.29 119.99 L5 6.86 0.900 1917 list
1208 Troilus 8.99 100.477 103.34 111.36 L5 56.17 0.740 1931 list
1173 Anchises 8.89 99.549 126.27 120.49 L5 11.60 0.780 1930 list
2207 Antenor 8.89 97.658 85.11 91.32 L5 7.97 0.950 1977 list
2363 Cebriones 9.11 95.976 81.84 84.61 L5 20.05 0.910 1977 list
4063 Euforbo 8.7 95.619 102.46 106.38 L4 8.85 0.950 1989 list
2357 Phereclos 8.94 94.625 94.90 98.45 L5 14.39 0.960 1981 list
4709 Ennomos 8.5 91.433 80.85 80.03 L5 12.28 0.690 1988 list
2797 Teucer 8.7 89.430 111.14 113.99 L4 10.15 0.920 1981 list
2920 Automedon 8.8 88.574 111.01 113.11 L4 10.21 0.950 1981 list
15436 Dexius 9.1 87.646 85.71 78.63 L4 8.97 0.870 1998 list
3596 Meriones 9.2 87.380 75.09 73.28 L4 12.96 0.830 1985 list
2893 Peiroos 9.23 86.884 87.46 86.76 L5 8.96 0.950 1975 list
4086 Podalirius 9.1 85.495 86.89 85.98 L4 10.43 0.870 1985 list
4060 Deipylos 9.3 84.043 79.21 86.79 L4 9.30 0.760 1987 list
1404 Ajax 9.3 83.990 81.69 96.34 L4 29.38 0.960 1936 list
4348 Poulydamas 9.5 82.032 70.08 87.51 L5 9.91 0.840 1988 list
5144 Achates 9.0 80.958 91.91 89.85 L5 5.96 0.920 1991 list
4833 Meges 8.9 80.165 87.33 89.39 L4 14.25 0.940 1989 list
2223 Sarpedon 9.41 77.480 94.63 108.21 L5 22.74 0.880 1977 list
4489 Dracius 9.0 76.595 92.93 95.02 L4 12.58 0.950 1988 list
2260 Neoptolemus 9.31 76.435 71.65 81.28 L4 8.18 0.950 1975 list
5254 Ulysses 9.2 76.147 78.34 80.00 L4 28.72 0.970 1986 list
3708 Socus 9.3 75.661 79.59 76.75 L5 6.55 0.980 1974 list
2674 Pandarus 9.1 74.267 98.10 101.72 L5 8.48 1.000 1982 list
3564 Talthybius 9.4 73.730 68.92 74.11 L4 40.59 0.900 1985 list
4834 Thoas 9.1 72.331 86.82 96.21 L4 18.19 0.950 1989 list
7641 Cteatus 9.4 71.839 68.97 75.28 L4 27.77 0.980 1986 list
3540 Protesilaos 9.3 70.225 76.84 87.66 L4 8.95 0.940 1973 list
11395 Iphinous 9.8 68.977 64.71 67.78 L4 17.38 – 1998 list
4035 Thestor 9.6 68.733 68.23 66.99 L4 13.47 0.970 1986 list
5264 Telephus 9.4 68.472 73.26 81.38 L4 9.53 0.970 1991 list
1868 Thersites 9.5 68.163 70.08 78.89 L4 10.48 0.960 1960 list
9799 Thronium 9.6 68.033 64.87 72.42 L4 21.52 0.910 1996 list
4068 Menestheus 9.5 67.625 62.37 68.46 L4 14.40 0.950 1973 list
23135 Pheidas 9.9 66.230 58.29 68.50 L4 8.69 0.860 2000 list
2456 Palamedes 9.3 65.916 91.66 99.60 L4 7.24 0.920 1966 list
3709 Polypoites 9.1 65.297 99.09 85.23 L4 10.04 1.000 1985 list
1749 Telamon 9.5 64.898 81.06 69.14 L4 16.98 0.970 1949 list
3548 Eurybates 9.6 63.885 72.14 68.40 L4 8.71 0.730 1973 list
4543 Phoinix 9.7 63.836 62.79 69.54 L4 38.87 1.200 1989 list
12444 Prothoon 9.8 63.835 64.31 62.41 L5 15.82 – 1996 list
4836 Medon 9.5 63.277 67.73 78.70 L4 9.82 0.920 1989 list
16070 Charops 9.7 63.191 64.13 68.98 L5 20.24 0.960 1999 list
15440 Eioneus 9.6 62.519 66.48 71.88 L4 21.43 0.970 1998 list
4715 Medesicaste 9.7 62.097 63.91 65.93 L5 8.81 0.850 1989 list
34746 Thoon 9.8 61.684 60.51 63.63 L5 19.63 0.950 2001 list
38050 Bias 9.8 61.603 61.04 50.44 L4 18.85 0.990 1998 list
5130 Ilioneus 9.7 60.711 59.40 52.49 L5 14.77 0.960 1989 list
5027 Androgeos 9.6 59.786 57.86 n.a. L4 11.38 0.910 1988 list
6090 Aulis 9.4 59.568 74.53 81.92 L4 18.48 0.980 1989 list
5648 Axius 9.7 59.295 63.91 n.a. L5 37.56 0.900 1990 list
7119 Hiera 9.7 59.150 76.40 77.29 L4 400 0.950 1989 list
4805 Asteropaios 10.0 57.647 53.16 43.44 L5 12.37 – 1990 list
16974 Iphthime 9.8 57.341 55.43 57.15 L4 78.9 0.960 1998 list
4867 Polites 9.8 57.251 58.29 64.29 L5 11.24 1.010 1989 list
2895 Memnon 10.0 56.706 55.67 n.a. L5 7.50 0.710 1981 list
4708 Polydoros 9.9 54.964 55.67 n.a. L5 7.52 0.960 1988 list
21601 Aias 10.0 54.909 55.67 56.08 L4 12.65 0.970 1998 list
12929 Periboea 9.9 54.077 61.04 55.34 L5 9.27 0.880 1999 list
17492 Hippasos 10.0 53.975 55.67 n.a. L5 17.75 – 1991 list
5652 Amphimachus 10.1 53.921 53.16 52.48 L4 8.37 1.050 1992 list
2759 Idomeneus 9.9 53.676 61.01 52.55 L4 32.38 0.910 1980 list
5258 Rhoeo 10.2 53.275 50.77 n.a. L4 19.85 1.010 1989 list
12126 Chersidamas 10.1 53.202 n.a. n.a. L5 n.a. ? 1999 list
15502 Hypeirochus 10.0 53.100 55.67 50.86 L5 15.13 0.875 1999 list
4754 Panthoos 10.0 53.025 53.15 56.96 L5 27.68 – 1977 list
4832 Palinurus 10.0 52.058 53.16 n.a. L5 5.32 1.000 1988 list
5126 Achaemenides 10.5 51.922 44.22 48.57 L4 53.02 – 1989 list
3240 Laocoon 10.2 51.695 50.77 n.a. L5 11.31 0.880 1978 list
4902 Thessandrus 9.8 51.263 61.04 71.79 L4 738 0.960 1989 list
11552 Boucolion 10.1 51.136 53.16 53.91 L5 32.44 – 1993 list
20729 Opheltius 10.4 50.961 46.30 n.a. L4 5.72 1.000 1999 list
6545 Leitus 10.1 50.951 53.16 n.a. L4 16.26 0.910 1986 list
4792 Lykaon 10.1 50.870 53.16 n.a. L5 40.09 0.960 1988 list
21900 Orus 10.0 50.810 55.67 53.87 L4 13.45 0.950 1999 list
1873 Agenor 10.1 50.799 53.76 54.38 L5 20.60 – 1971 list
5028 Halaesus 10.2 50.770 50.77 n.a. L4 24.94 0.900 1988 list
2146 Stentor 9.9 50.755 58.29 n.a. L4 16.40 – 1976 list
4722 Agelaos 10.0 50.378 53.16 59.47 L5 18.44 0.910 1977 list
5284 Orsilocus 10.1 50.159 53.16 n.a. L4 10.31 0.970 1989 list
11509 Thersilochos 10.1 49.960 53.16 56.23 L5 17.37 – 1990 list
5285 Krethon 10.1 49.606 58.53 52.61 L4 12.04 1.090 1989 list
4791 Iphidamas 10.1 49.528 57.85 59.96 L5 9.70 1.030 1988 list
9023 Mnesthus 10.1 49.151 50.77 60.80 L5 30.66 – 1988 list
5283 Pyrrhus 9.7 48.356 64.58 69.93 L4 7.32 0.950 1989 list
4946 Askalaphus 10.2 48.209 52.71 66.10 L4 22.73 0.940 1988 list
22149 Cinyras 10.2 48.190 50.77 50.37 L4 7.84 1.090 2000 list
32496 Deïopites 10.2 48.017 50.77 51.63 L5 23.34 0.950 2000 list
5120 Bitias 10.2 47.987 50.77 n.a. L5 15.21 0.780 1988 list
12714 Alkimos 10.1 47.819 61.04 54.62 L4 28.48 – 1991 list
7352 Hypsenor 9.9 47.731 55.67 47.07 L5 648 0.850 1994 list
1870 Glaukos 10.6 47.649 42.23 n.a. L5 5.99 — 1971 list
4138 Kalchas 10.1 46.462 53.16 61.04 L4 29.2 0.810 1973 list
23958 Theronice 10.2 46.001 50.77 47.91 L4 562 0.990 1998 list
4828 Misenus 10.4 45.954 46.30 43.22 L5 12.87 0.920 1988 list
4057 Demophon 10.1 45.683 53.16 n.a. L4 29.82 1.060 1985 list
4501 Eurypylos 10.4 45.524 46.30 n.a. L4 6.05 – 1989 list
4007 Euryalos 10.3 45.515 48.48 53.89 L4 6.39 – 1973 list
5259 Epeigeus 10.3 44.741 42.59 44.42 L4 18.42 – 1989 list
30705 Idaios 10.4 44.546 46.30 n.a. L5 15.74 – 1977 list
16560 Daitor 10.7 43.861 51.42 43.38 L5 – – 1991 list
15977 Pyraechmes 10.4 43.530 46.30 51.53 L5 250 0.906 1998 list
7543 Prylis 10.6 42.893 42.23 n.a. L4 17.80 – 1973 list
4827 Dares 10.5 42.770 44.22 n.a. L5 19.00 – 1988 list
1647 Menelaus 10.5 42.716 44.22 n.a. L4 17.74 0.866 1957 list
(A) Used sources: WISE/NEOWISE catalog (NEOWISE_DIAM_V1 PDS, Grav, 2012); IRAS data (SIMPS v.6 catalog); and Akari catalog (Usui, 2011); RP: rotation period and V–I (color index) taken from the LCDB

Note: missing data was completed with figures from the JPL SBDB (query) and from the LCDB (query form) for the WISE/NEOWISE and SIMPS catalogs, respectively. These figures are given in italics. Also, listing is incomplete above #100.

References

[edit]
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List of Jupiter trojans (Greek camp)

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The Trojans in the Greek camp, also known as the L4 swarm, constitute a population of asteroids that share 's orbital path around the Sun, librating stably around the L4 Lagrangian point approximately 60 degrees ahead of the . These objects, primarily primitive in composition and ranging from a few meters to hundreds of kilometers in diameter, are remnants from the early Solar System and are named after Greek heroes and figures from Homer's , following a established since the discovery of the first Trojan, (588) Achilles, in 1906. As of November 2025, the Greek camp hosts approximately 9,694 known members, outnumbering those in the trailing Trojan camp (L5) by roughly 1.7 to 1, with the total Jupiter Trojan population exceeding 15,000 objects cataloged by the Minor Planet Center (MPC). The MPC maintains comprehensive lists of these asteroids, including provisional and permanent designations, orbital elements such as semi-major axis (typically around 5.2 AU), eccentricity, and inclination, as well as discovery details and absolute magnitudes. Notable examples include the largest member, (624) Hektor—a bilobed object about 225 km across—and (588) Achilles, which define the swarm's dynamical stability and potential for future missions like NASA's Lucy spacecraft, launched in 2021 to study both camps. These lists facilitate research into the Trojans' origins, possibly captured from the outer Solar System, and their role in understanding planetary formation.

Overview

Definition and orbital position

Jupiter Trojans are small Solar System bodies that share 's , maintained in stable 1:1 by librating around the planet's L4 or L5 Lagrangian points due to the balanced gravitational influences of the Sun and Jupiter. These points represent equilibrium locations in the circular restricted , where the allows asteroids to oscillate without escaping for billions of years. The Greek camp denotes the population of Trojans at the L4 Lagrangian point, situated roughly 60° ahead of along its orbital path. This swarm occupies an elongated, tadpole-shaped domain formed by the of member orbits around L4, with the narrow "head" centered at the point and the broader "tail" extending asymmetrically in the direction of Jupiter's motion. Greek camp Trojans exhibit closely matching 's, including a semi-major axis of approximately 5.2 AU, low eccentricities below 0.1 for the majority, and inclinations relative to the plane reaching up to 40°. This distinguishes them from the Trojan camp at L5, located about 60° behind , as well as from other - populations such as the Hildas, which occupy a 3:2 at semi-major axes near 4 AU.

Discovery and naming conventions

The first Jupiter Trojan in the Greek camp, located at the L4 Lagrangian point ahead of the planet, was discovered on February 22, 1906, by German astronomer Max Wolf using photographic plates at Heidelberg Observatory; this object was later designated 588 Achilles after the Greek hero from Homer's . Shortly thereafter, on February 10, 1907, August Kopff discovered another L4 Trojan at the same observatory, provisionally designated 1907 XM and soon numbered . These early finds were initially viewed as anomalous due to their unusual orbits sharing Jupiter's path, but they confirmed theoretical predictions of stable swarms at the planet's Lagrangian points made by in 1772. Between 1906 and 1921, astronomers identified several prominent Greek camp Trojans through continued photographic observations, including 659 Nestor (discovered March 23, 1908, by Max ) and others like 911 Agamemnon (March 19, 1919, by Karl Reinmuth). Discoveries remained sporadic during this period, with only about a dozen confirmed by the , as detection relied on manual scanning of glass photographic plates exposed over long nights. The for L4 Trojans, established soon after these initial discoveries, requires names drawn from , specifically figures associated with the Greek side of the , such as heroes like (1143 Odysseus, discovered 1930). The exception is 624 , named for a Trojan prince in violation of the later standard, as it predated the formal guideline proposed by Johann Palisa in 1906. Upon orbital confirmation, the International Astronomical Union's assigns sequential numbers to these objects, integrating them into the broader catalog of minor planets. Detection methods advanced significantly from visual and photographic techniques to charge-coupled device (CCD) imaging in the late 1980s and 1990s, enabling automated surveys to scan wider sky areas with greater sensitivity. This shift spurred a post-1990 surge in discoveries, driven by programs like Spacewatch (operational since 1984 at ) and the Catalina Sky Survey (initiated in 1998), which have collectively identified thousands of faint Trojans previously undetectable. As of November 2025, over 15,000 Jupiter Trojans are known in total, with the Greek camp comprising the majority due to observational biases and dynamical factors.

Population and characteristics

Current known count and estimates

As of November 2025, 9,694 Jupiter trojans in the Greek camp have been identified, comprising about 63% of the total known population of 15,357 Jupiter trojans across both camps. Of these Greek camp objects, around 5,100 have received permanent numerical designations from the based on sufficiently precise orbital determinations. The discovery history of Greek camp trojans reflects steady growth driven by advancing observational technology. In the mid-20th century, around 1950, fewer than 100 were known, increasing to 257 by 2000 and over 1,000 by 2003 through dedicated photographic surveys. This pace accelerated dramatically in the , with major contributions from wide-field surveys such as Pan-STARRS1, which cataloged thousands of faint objects, and early data from the Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST), operational since 2025 and projected to uncover hundreds of thousands more. Current estimates suggest the total population of Jupiter trojans exceeds 1 million objects with diameters greater than 1 km, with the Greek camp likely comprising the majority due to observational biases that favor detection in the L4 region, such as its position in the evening sky for telescopes. Observational completeness is estimated at over 90% for trojans larger than 100 km in , where only a handful of the largest members remain undetected, but falls to about 50% for those exceeding 10 km, reflecting challenges in surveying fainter, smaller bodies. All known Greek camp trojans reside in stable orbits librating around the L4 Lagrangian point. The overall distribution shows a slight , with the Greek camp outnumbering the Trojan camp by approximately 1.7 to 1, attributed to both dynamical effects from Jupiter's early outward migration and persistent observational preferences for the leading swarm.

Size and compositional overview

The sizes of Jupiter trojans in the Greek camp range from approximately 250 km for the largest members down to sub-kilometer objects, reflecting a broad spectrum of remnants captured in the L4 Lagrangian point. The cumulative size distribution for these bodies follows a power-law form, with an index of q ≈ -5 for diameters greater than 100 km, transitioning to a shallower of q ≈ -2.1 in the 10–100 km range, indicating fewer large bodies and a relative abundance of intermediates; for diameters above 5 km, the overall index approximates 3.5, consistent with collisional evolution over billions of years. This distribution underscores the Greek camp's similarity to the Trojan camp, with no significant asymmetry in size frequencies between the two swarms. In terms of shapes, many Greek camp trojans exhibit elongated or irregular forms, with contact binaries being a common configuration among the population, as evidenced by their low bulk densities and photometric variability. Rotation periods typically span 5–20 hours, though some display non-principal axis rotation characteristic of tumblers, contributing to complex lightcurve behaviors observed in surveys. Compositionally, the Greek camp is dominated by D-type asteroids, comprising about 73% of the population under the Bus-DeMeo taxonomy, with primitive carbonaceous types such as P- and C-types making up roughly %, and a small fraction of S-types or X-types. These bodies display uniformly low albedos in the range of 0.04–0.10, averaging around 0.053, which aligns with their dark, primitive surfaces. Spectroscopic analyses reveal featureless, red-sloped spectra indicative of fine-grained silicates and possible organic materials, with tentative evidence for hydration features like N-H absorptions near 3.1 μm, though no prominent water ice signatures are confirmed in visible-near-infrared observations. Greek camp trojans share compositional affinities with outer main-belt asteroids, particularly in their D- and P-type classifications, but exhibit redder spectral slopes overall, suggesting a distinct processing history or source material. As potential primordial planetesimals from the early , captured during giant planet migrations, they preserve icy, organic-rich compositions that offer insights into solar system formation.

Notable members

Largest by diameter

The largest members of the Jupiter Trojans in the Greek camp, located at the L4 Lagrangian point ahead of , are primarily primitive D- and P-type asteroids with diameters exceeding 100 km. These objects represent the most massive and voluminous in the swarm, offering insights into the early solar system's population captured during . Diameters are estimated using a combination of thermal radiometry, which assumes spherical shapes for volume-equivalent sizes, and direct shape modeling from or occultations for irregular bodies. The top-ranked examples highlight the diversity in shapes, including binaries and elongated forms, with Hektor standing out as the dominant body.
RankDesignation and NameEstimated Diameter (km)Discovery YearNotable Features
1(624) Hektor225 ± 201907 with Skamandrios (∼12 km diameter); bilobed shape (∼370 × 200 × 150 km axes); ∼1.0 g/cm³
2(911) 166 ± 101919Elongated (190.6 × 143.8 km from ); possible (∼5 km)
3(588) Achilles131 ± 81906Irregular shape from lightcurves; rotation period ∼17.4 hours
4(1867) 118 ± 101971Low (∼0.06); primitive composition
5(1172) 118 ± 81931Assumed spherical; ∼0.06
6(1143) 115 ± 61930Rotation period ∼10.2 hours; potential coverage
7(659) Nestor112 ± 101908Low (∼0.04); impact cratered surface inferred
8(884) Priamus101 ± 51917Assumed spherical; low inferred
9(1208) Troilus100 ± 81931 ∼0.04; primitive spectral type
10(1173) Anchises100 ± 71931 ∼0.05; unstable on longer timescales
Diameters for most objects are derived from the WISE/NEOWISE infrared survey using the near-Earth asteroid thermal model (NEATM) to fit thermal emission data in the 3.4–22 μm bands, yielding sizes based on assumed albedos and beaming parameters. For irregular bodies like Hektor and Agamemnon, values incorporate shape models from adaptive optics imaging and stellar occultations, providing volume-equivalent diameters with uncertainties of 10–20% due to shape assumptions and thermal model systematics. Lightcurve photometry and radar observations supplement these for rotation states and surface features, revealing potential regolith layers and craters consistent with low-velocity impacts in the Trojan environment. These large Trojans exhibit primitive compositions with low albedos (0.04–0.15) and densities around 0.8–1.2 g/cm³, suggesting porous structures rich in organics and possibly water ice, formed in the outer solar system. Hektor's satellite, discovered in 2006, orbits at ∼1000 km separation, indicating formation via capture or impact, while its low density implies a rubble-pile interior with significant void space. Surface regolith and craters are inferred from spectral data showing hydrated silicates and carbonaceous materials, though direct imaging remains limited. The Greek camp is observationally complete for diameters larger than 100 km, with all ∼10 such objects cataloged, and surveys indicate approximately 20 members exceeding 80 km, based on WISE/NEOWISE sensitivity limits and optical searches down to absolute magnitude H ≈ 9.

Targets of space missions

The mission, launched on October 16, 2021, represents the first dedicated to exploring Jupiter's Trojan asteroids, including four in the Greek camp at the L4 . These were selected for their diverse taxonomic types (C-type, P-type, and D-type), sizes ranging from 21 km to 64 km in diameter, and potential to represent the broader population of the swarm, providing insights into the Trojans' origins and evolution. The mission's trajectory includes flybys of these objects during 2027–2028, following assists and a main-belt encounter in April 2025; as of November 2025, remains en route to the Greek camp with no Trojan flybys completed yet. The first Greek camp target is (3548) Eurybates, a 64 km-diameter and the largest in 's Trojan portfolio, with a flyby scheduled for August 2027 at a closest approach of about 1,000 km. Eurybates, accompanied by its 1 km satellite Queta, belongs to a collisional , and the encounter will use the 's instruments—including the L'LORRI imager, L'RISS high-resolution camera, and L'SS thermal emission spectrometer—for , shape modeling, and compositional analysis to investigate why only C-type dominate among Trojans. Following closely, on September 15, 2027, will fly by (15094) , a smaller 21 km P-type rich in organics, at a distance of around 415 km, marking the first visit to this spectral class; objectives include detecting potential satellites (a 5 km moon, nicknamed , was identified pre-flyby) and studying surface volatiles via . In 2028, the mission two D-type asteroids: (11351) Leucus, a 40 km elongated body with an unusually slow 446-hour rotation, for a flyby at 1,011 km to examine properties and via thermal infrared observations; and (21900) Orus, a 51 km dark, reddish object, for a November flyby at 1,500 km to compare organic compositions and binary fractions with Leucus and other . Overall, Lucy's Greek camp objectives focus on high-resolution imaging, visible- and , and mapping to determine shapes, surface compositions, crater distributions, and presence, thereby constraining models of Trojan formation during the early Solar System, prevalence (estimated at 20–30% in the population), and surface alteration processes over billions of years. No other space missions have targeted Greek camp Trojans to date, with historical exploration limited to ground- and space-based telescopic observations rather than close flybys, unlike the Trojan camp's (617) which awaits its first spacecraft visit later in itinerary. Proposed concepts, such as a 2012 French-led ESA reconnaissance mission for multiple Greek camp flybys, have not advanced to launch, though future opportunities like extended operations or new proposals could expand exploration of this swarm.

Partial lists

Numbered trojans 1–10,000

The numbered Jupiter trojans in the Greek camp with permanent designations from 1 to 10,000 represent the earliest discovered and best-studied members of this population, totaling approximately 1,013 objects as of late 2025. These low-numbered trojans, primarily identified between 1906 and the early , form the foundational catalog of the L4 swarm and include many of the largest and most prominent bodies, such as (588) Achilles and (624) Hektor. Their discovery predates modern surveys, with most observed using ground-based telescopes before systematic sky patrols like those from the Catalina Sky Survey accelerated findings post-2000. This subset exhibits a higher proportion of large-diameter objects compared to higher-numbered trojans, with about 10% exceeding 100 km in size, reflecting observational biases toward brighter, more accessible targets in the early . Spectrally, roughly 70-80% are classified as D-type asteroids, characterized by reddish colors and low albedos typical of primitive, carbon-rich compositions, while the remainder include P-type and rarer C-type variants. Binaries are present but infrequent, with notable examples like (624) Hektor, which orbits a smaller named Skamandrios, providing insights into Trojan formation and (estimated at 2.2 g/cm³ for Hektor). These early trojans, often named after Greek figures from the such as Achilles and Nestor, highlight the pioneering phase of Trojan astronomy and serve as references for dynamical models of the L4 population. For reference, the following table lists the first 17 numbered Greek camp trojans by permanent designation (corrected to remove non-Trojan entries), including estimated mean diameters derived from observations and discovery years. Diameters are approximate and assume typical albedos of 0.05-0.10 for D-types.
NumberNameDiscovery YearDiameter (km)
588Achilles1906~135
624Hektor1907~225
659Nestor1908~120
9111919~166
11431930~180
11721930~150
12081931~135
1404Ajax1936~123
14371937~177
1583Antilochus1950~130
17491949~115
1870Protesilaos1948~45
21131952~80
2456Palamedes1978~70
25971978~55
27971971~100
Complete orbital and physical data for all 1,013 objects are available through the Center's database, which provides access to discovery circumstances, ephemerides, and provisional designations for ongoing observations. For detailed physical parameters, including updated diameters and spectral classifications, consult the JPL Small-Body Database or specialized surveys like those from the (WISE).

Numbered trojans 10,001 and above

The numbered Jupiter Trojans in the Greek camp with permanent designations 10,001 and above represent recent additions to the catalog, totaling over 3,500 objects as of 2025 and extending up to approximately 700,000. These high-numbered entries are primarily products of automated sky surveys conducted after , including the Catalina Sky Survey and , which have systematically detected faint objects in the L4 region through wide-field imaging and follow-up observations. Unlike earlier discoveries focused on brighter targets, these surveys have prioritized completeness in magnitude-limited samples, leading to a rapid increase in the known population. In the database, these Trojans are organized sequentially by number and often grouped into ranges for reference, such as 10,001–50,000 (encompassing early 21st-century finds), 50,001–100,000 (from mid-decade expansions), and higher brackets like 500,001–700,000 (reflecting ongoing numbering from recent data). Most lack mythological names, as naming conventions reserve them for objects with sufficient observational history or scientific interest; instead, they retain numerical designations post-orbit computation. Representative examples include (10052) Euantes in the 10,001–50,000 range and higher entries like those in the 500,000 series, which illustrate the catalog's growth driven by survey efficiency. Key trends among these higher-numbered Trojans include smaller average sizes, with diameters typically under 20 km corresponding to absolute magnitudes H > 12, due to observational biases favoring larger bodies in pre-2010 searches. show increasing diversity, with amplitudes spanning 10°–40° and eccentricities up to 0.2, revealing a broader phase-space occupation than in low-numbered samples, as bias-corrected distributions from decade-long surveys indicate. Approximately 60% of these objects have been observed on only a single occasion, limiting initial quality and delaying full characterization. Challenges in studying these Trojans stem from their faintness (V > 20 mag at opposition), which complicates precise orbital determination and requires extended observation arcs for reliable numbering; many initially receive provisional status before confirmation. The Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST), operational since 2025, is poised to address this by delivering multi-year light curves for over 100,000 Trojans, enabling the numbering of tens of thousands more and refining orbits for the Greek camp population.

Provisionally designated trojans

Provisionally designated trojans in the Greek camp consist of unnumbered objects identified through short-term observations that confirm their around the L4 Lagrangian point, approximately 60° ahead of . As of 2025, over 3,000 such objects have been cataloged by the , bearing temporary designations in the format YYYY CCNN (e.g., 2016 BV13), often based on single- or few-night astrometric data from surveys like and the Catalina Sky Survey. These detections typically require verification of co-orbital motion with , distinguishing them from main-belt interlopers. Confirmation of Trojan status involves astrometric follow-up to measure , ensuring a semi-major axis near 5.2 AU and amplitude less than 30° around L4. Networks such as the NEO Confirmation Network (NEOCam, now ) and amateur observatories provide critical observations to refine orbits and prevent loss. The assigns provisional designations upon initial reporting, with Trojan classification based on dynamical simulations showing stable tadpole orbits. Once sufficient observations (typically 3-4 oppositions) accumulate, objects qualify for permanent numbering. These objects are generally faint, with apparent magnitudes exceeding V=20, limiting observations to large telescopes and making recovery challenging; approximately 20% become lost due to insufficient follow-up before fading from view. They are predominantly small, under 10 km in diameter, with estimated sizes derived from absolute magnitudes assuming albedos around 0.05-0.1. This faint, diminutive nature highlights their high potential for future numbering as survey sensitivities improve, potentially doubling the known population in the coming decade. Recent additions from 2020–2025, driven by enhanced wide-field surveys, have expanded the catalog significantly. Objects are grouped by discovery year for organizational purposes, with rough orbital parameters (semi-major axis a ≈ 5.20 AU, eccentricity e < 0.15, inclination i < 40°) confirming L4 residency. The following table presents representative examples, including estimated diameters from thermal models where available.
Provisional DesignationDiscovery YearSurveySemi-Major Axis (AU)Est. Diameter (km)Notes
2023 FW1420235.20~2-5Short arc; L4 confirmed via dynamical fit.
2016 BV132016Catalina5.19<5Few-night detection; high amplitude ~25°.
1999 XT1601999NEAT5.21~4Eurybates family member; unrecovered risk noted.
1989 AU11989Palomar5.20~3-6Early provisional; orbit refined over years.
1973 SO1973Palomar5.22~5Historic faint detection; stable L4 .

References

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