4867 Polites is a Jupiter trojan from the

Trojan camp This is a list of Jupiter trojans that lie in the Trojan camp, an elongated curved region around the trailing Lagrangian point, 60° behind Jupiter. All the asteroids at the trailing point have names corresponding to participants on the Troj ...

, approximately in diameter. It was discovered on 27 September 1989, by American astronomer

Carolyn Shoemaker Carolyn Jean Spellmann Shoemaker (June 24, 1929 – August 13, 2021) was an American astronomer and a co-discoverer of Comet Shoemaker–Levy 9. She discovered 32 comets (then a record for the most by an individual) and more than 500 astero ...

at the Palomar Observatory in California. The dark Jovian asteroid belongs to the 80 largest Jupiter trojans and has a rotation period of 11.2 hours. It was named after the Trojan prince Polites from Greek mythology.

Orbit and classification

''Polites'' is a dark Jovian asteroid in a 1:1

orbital resonance In celestial mechanics, orbital resonance occurs when orbiting bodies exert regular, periodic gravitational influence on each other, usually because their orbital periods are related by a ratio of small integers. Most commonly, this relationsh ...

with Jupiter. It is located in the trailering

at the Gas Giant's Lagrangian point, 60 ° behind its orbit . It is also a non-

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

asteroid of the Jovian background population. It orbits the Sun at a distance of 5.1–5.3 AU once every 11 years and 9 months (4,285 days; semi-major axis of 5.16 AU). Its orbit has an

eccentricity Eccentricity or eccentric may refer to: * Eccentricity (behavior), odd behavior on the part of a person, as opposed to being "normal" Mathematics, science and technology Mathematics * Off-Centre (geometry), center, in geometry * Eccentricity (g ...

of 0.02 and an

inclination Orbital inclination measures the tilt of an object's orbit around a celestial body. It is expressed as the angle between a reference plane and the orbital plane or axis of direction of the orbiting object. For a satellite orbiting the Eart ...

of 27 ° with respect to the

ecliptic The ecliptic or ecliptic plane is the orbital plane of the Earth around the Sun. From the perspective of an observer on Earth, the Sun's movement around the celestial sphere over the course of a year traces out a path along the ecliptic agains ...

. The body's

observation arc In observational astronomy, the observation arc (or arc length) of a Solar System body is the time period between its earliest and latest observations, used for tracing the body's path. It is usually given in days or years. The term is mostly use ...

begins with its first observation as ' at Palomar in September 1988, or one year prior to its official discovery observation.

Physical characteristics

''Polites'' is an assumed

C-type asteroid C-type (carbonaceous) asteroids are the most common variety, forming around 75% of known asteroids. They are volatile-rich and distinguished by a very low albedo because their composition includes a large amount of carbon, in addition to rocks ...

. Its V–I color index of 1.01 is one of the highest among the larger Jupiter trojans ''(see table below)''.

Rotation period

In August 2010, a rotational

lightcurve In astronomy, a light curve is a graph of light intensity of a celestial object or region as a function of time, typically with the magnitude of light received on the y axis and with time on the x axis. The light is usually in a particular freq ...

of ''Polites'' was obtained from photometric observations over five nights by Linda French at the

Cerro Tololo Inter-American Observatory The Cerro Tololo Inter-American Observatory (CTIO) is an astronomical observatory located on Cerro Tololo in the Coquimbo Region of northern Chile, with additional facilities located on Cerro Pachón about to the southeast. It is approximately ...

in Chile. Lightcurve analysis gave a tentative rotation period of 9.21 hours with a low brightness variation of 0.09

magnitude Magnitude may refer to: Mathematics *Euclidean vector, a quantity defined by both its magnitude and its direction *Magnitude (mathematics), the relative size of an object *Norm (mathematics), a term for the size or length of a vector *Order of ...

(). Follow-up observations on a yearly basis by

Robert D. Stephens Robert D. Stephens (born 1955) is an American amateur astronomer and a prolific Photometry (astronomy), photometrist of minor planets at the Center for Solar System Studies , Rancho Cucamonga in California, United States. Career By profession, ...

and Daniel Coley at the Center for Solar System Studies gave several lightcurves during 2013–2018. The best-rated one from January 2016 gave a period of hours and an amplitude of 0.15 magnitude ().

Diameter and albedo

According to the surveys carried out by the Japanese Akari satellite, the

NEOWISE Wide-field Infrared Survey Explorer (WISE, observatory code C51, Explorer 92 and SMEX-6) is a NASA infrared astronomy space telescope in the Explorers Program. It was launched in December 2009, and placed in hibernation mode in February 201 ...

mission of NASA's

Wide-field Infrared Survey Explorer Wide-field Infrared Survey Explorer (WISE, observatory code C51, Explorer 92 and SMEX-6) is a NASA infrared astronomy space telescope in the Explorers Program. It was launched in December 2009, and placed in hibernation mode in February 201 ...

, and the Infrared Astronomical Satellite

IRAS The Infrared Astronomical Satellite (Dutch: ''Infrarood Astronomische Satelliet'') (IRAS) was the first space telescope to perform a survey of the entire night sky at infrared wavelengths. Launched on 25 January 1983, its mission lasted ten mo ...

, ''Polites'' measures between 57.25 and 65.16 kilometers in diameter and its surface has an

albedo Albedo (; ) is the measure of the diffuse reflection of solar radiation out of the total solar radiation and measured on a scale from 0, corresponding to a black body that absorbs all incident radiation, to 1, corresponding to a body that refl ...

between 0.071 and 0.078. The ''Collaborative Asteroid Lightcurve Link'' assumes a standard albedo for a carbonaceous asteroid of 0.057 and calculates a diameter of 58.29 kilometers based on an

absolute magnitude Absolute magnitude () is a measure of the luminosity of a celestial object on an inverse logarithmic astronomical magnitude scale. An object's absolute magnitude is defined to be equal to the apparent magnitude that the object would have if it ...

of 9.9.

Naming

This

minor planet According to the International Astronomical Union (IAU), a minor planet is an astronomical object in direct orbit around the Sun that is exclusively classified as neither a planet nor a comet. Before 2006, the IAU officially used the term ''mino ...

was named by the discoverer from

Greek mythology A major branch of classical mythology, Greek mythology is the body of myths originally told by the ancient Greeks, and a genre of Ancient Greek folklore. These stories concern the origin and nature of the world, the lives and activities ...

after the Trojan prince Polites, son of King Priam and

Hecuba Hecuba (; also Hecabe; grc, Ἑκάβη, Hekábē, ) was a queen in Greek mythology, the wife of King Priam of Troy during the Trojan War. Description Hecuba was described by the chronicler Malalas in his account of the ''Chronography'' as "da ...

. He was killed with a spear handled by Achille's son

Neoptolemus In Greek mythology, Neoptolemus (; ), also called Pyrrhus (; ), was the son of the warrior Achilles and the princess Deidamia, and the brother of Oneiros. He became the mythical progenitor of the ruling dynasty of the Molossians of ancient Ep ...

(Pyrrhus), who was the most ruthless of the Greeks. During the fall of Troy, he invaded Priam's great house and chased Polites until he cornered and slaughtered him in front of his parents. The official naming citation was published by the Minor Planet Center on 4 June 1993 ().

Orbit and classification

Physical characteristics

Rotation period

Diameter and albedo

Naming

Notes

References

External links