is a

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 ...

, first observed by the

Sloan Digital Sky Survey The Sloan Digital Sky Survey or SDSS is a major multi-spectral imaging and spectroscopic redshift survey using a dedicated 2.5-m wide-angle optical telescope at Apache Point Observatory in New Mexico, United States. The project began in 2000 a ...

Collaboration at Apache Point Observatory, New Mexico, on 12 September 2006. It was the fifth and largest such body discovered, approximately 180 kilometers in diameter. , it is 30.3 AU from Neptune.

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 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 leading group, which follow 60 ° ahead Neptune's orbit. It orbits the Sun with a semi-major axis 29.925 AU of at a distance of 29.0–30.9 AU once every 163 years and 8 months (59,793 days). Its orbit has an eccentricity of 0.03 and an inclination of 8 ° with respect to the ecliptic.

Physical characteristics

The discoverers estimate that has a mean-diameter of 180 kilometers based on a magnitude of 22.0. Based on a generic magnitude-to-diameter conversion, it measures approximately 130 kilometers in diameter using an absolute magnitude of 7.5 with an assumed albedo of 0.10.

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

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