is an eccentric

Neptune trojan Neptune trojans are bodies that orbit the Sun near one of the stable Lagrangian points of Neptune, similar to the Trojan (astronomy), trojans of other planets. They therefore have approximately the same orbital period as Neptune and follow rough ...

trailing

Neptune Neptune is the eighth planet from the Sun and the farthest known planet in the Solar System. It is the fourth-largest planet in the Solar System by diameter, the third-most-massive planet, and the densest giant planet. It is 17 times ...

's orbit in the outer Solar System, approximately 70 kilometers in diameter. It was first observed on 24 May 2004, by astronomers at the Mauna Kea Observatories on Hawaii, United States. It was the eighth

identified and the second in

's Lagrangian point.

Orbit and classification

Neptune trojans are

resonant trans-Neptunian object In astronomy, a resonant trans-Neptunian object is a trans-Neptunian object (TNO) in mean-motion orbital resonance with Neptune. The orbital periods of the resonant objects are in a simple integer relations with the period of Neptune, e.g. 1:2, 2 ...

s (TNO) in a 1:1 mean-motion orbital resonance with Neptune. These Trojans have a

semi-major axis In geometry, the major axis of an ellipse is its longest diameter: a line segment that runs through the center and both foci, with ends at the two most widely separated points of the perimeter. The semi-major axis (major semiaxis) is the long ...

and an orbital period very similar to Neptune's (30.10 AU; 164.8 years). belongs to the trailing group, which follow 60 ° behind Neptune's orbit. It orbits the Sun with a semi-major axis of 30.370 AU at a distance of 24.7–36.1 AU once every 167 years and 4 months (61,132 days). Its orbit has a notably high eccentricity of 0.19 and an inclination of 14 ° with respect to the ecliptic.

Orbital instability

is not a primordial Neptune trojan, and will leave the region on a relatively short time scale. The orbit of a Neptune trojan can only be stable when the eccentricity is less than 0.12. Its lifetime as a trailing Neptune trojan is on the

order Order, ORDER or Orders may refer to: * Categorization, the process in which ideas and objects are recognized, differentiated, and understood * Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of d ...

of 100,000 years into the future.

Physical properties

Diameter and albedo

Based on a generic magnitude-to-diameter conversion, it measures approximately 71 kilometers in diameter using an absolute magnitude of 8.9 and an assumed albedo of 0.10. It is one of the smaller bodies among the first 17 Neptune trojans discovered so far, which measure between 60 and 200 kilometers (for an absolute magnitude of 9.3–6.6 and an assumed albedo of 0.10). Other estimates, implying a higher albedo than 0.10, gave a diameter of approximately 56 kilometers.

Numbering and naming

Due to its orbital uncertainty, this minor planet has not been numbered and its official

discoverers Discovery is the act of detecting something new, or something previously unrecognized as meaningful. With reference to sciences and academic disciplines, discovery is the observation of new phenomena, new actions, or new events and providing ...

have not been determined. If named, it will follow the naming scheme already established with

385571 Otrera 385571 Otrera, provisional designation , is a Neptune trojan leading Neptune's orbit in the outer Solar System. It was discovered by American astronomers Scott Sheppard and Chad Trujillo at Las Campanas Observatory on 16 October 2004. It measures ...

, which is to name these objects after figures related to the

Amazons In Greek mythology, the Amazons (Ancient Greek: Ἀμαζόνες ''Amazónes'', singular Ἀμαζών ''Amazōn'', via Latin ''Amāzon, -ŏnis'') are portrayed in a number of ancient epic poems and legends, such as the Labours of Hercules, ...

, an all-female warrior tribe that fought in the Trojan War on the side of the Trojans against the Greek.

References

External links

MPEC 2011-O47 : 2004 KV18
''MPEC –Minor Planet Electronic Circular'' * * {{DEFAULTSORT:2004 KV18 # Minor planet object articles (unnumbered) 20040524