(

provisional designation Provisional designation in astronomy is the naming convention applied to astronomical objects immediately following their discovery. The provisional designation is usually superseded by a permanent designation once a reliable orbit has been calcu ...

) is a

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 ...

and binary system, located in the outermost region of the Solar System. It was discovered on 26 December 2000, by astronomers with the Spacewatch survey at Kitt Peak Observatory near Tucson, Arizona. The reddish object stays in a rare 3:8 resonance with

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 ...

. A smaller companion was discovered by the Hubble Space Telescope in October 2002. , neither the

primary body A primary (also called a gravitational primary, primary body, or central body) is the main physical body of a gravitationally bound, multi-object system. This object constitutes most of that system's mass and will generally be located near the syst ...

nor its satellite have been named.

Orbit and classification

orbits the Sun at a distance of 41.0–73.8 AU once every 434 years and 9 months (158,805 days;

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 ...

of 57.39 AU). Its orbit has an eccentricity of 0.29 and an inclination of 20 ° with respect to the ecliptic. The body's observation arc begins with its official discovery observation by Spacewatch on 26 December 2000. It last came to perihelion in 1979, and is currently at about 46.5 AU from the Sun, with an apparent magnitude of 21.54. It will reach aphelion in December 2197. is a

that stays in a rare 3:8 mean-motion orbital resonance with

, orbiting exactly three times the Sun for every 8 orbits Neptune does. There are currently two other objects known to have the same resonant type: and . Due to its relatively large distance to Neptune, a classification as an extended-scattered or

detached object Detached objects are a dynamical class of minor planets in the outer reaches of the Solar System and belong to the broader family of trans-Neptunian objects (TNOs). These objects have orbits whose points of closest approach to the Sun (perihelion ...

was also considered earlier on (Lykawka, 2006). However, improved observations and long-term numerical integrations of the object's orbit by Emel’yanenko and Kiseleva (84% probability) and the

Deep Ecliptic Survey The Deep Ecliptic Survey (DES) is a project to find Kuiper belt objects (KBOs), using the facilities of the National Optical Astronomy Observatory (NOAO). The principal investigator is Robert L. Millis. Since 1998 through the end of 2003, the sur ...

– with all alternative integrations in agreement, showing a minimum perihelion distance of 38.2 AU – have since secured its 3:8 orbital resonance with Neptune.

Numbering and naming

This minor planet was numbered by the

Minor Planet Center The Minor Planet Center (MPC) is the official body for observing and reporting on minor planets under the auspices of the International Astronomical Union (IAU). Founded in 1947, it operates at the Smithsonian Astrophysical Observatory. Function ...

on 4 May 2004, receiving the number in the minor planet catalog (). , it has not been named. According to the established naming conventions, it will be given a mythological name associated with the underworld.

Physical characteristics

The surface of is moderately red in the visible part of the spectrum. Its IR spectral type transitions from the very red (RR) to the intermediate blue-red (BR). Alternatively a BR-spectral type has also been assumed. The object's B−V and V–R

color indices In astronomy, the color index is a simple numerical expression that determines the color of an object, which in the case of a star gives its temperature. The lower the color index, the more blue (or hotter) the object is. Conversely, the large ...

have also been measured several times, giving an averaged value of close to 1.0 and 0.5, respectively, for a combined B−R magnitude of 1.50.

Diameter and albedo

In 2010, observations with the

Herschel Space Observatory The Herschel Space Observatory was a space observatory built and operated by the European Space Agency (ESA). It was active from 2009 to 2013, and was the largest infrared telescope ever launched until the launch of the James Webb Space Telesc ...

constrained the object's geometric albedo to no darker than 8%, and allowed to place an upper limit on its effective mean diameter of , as no thermal radiation had been detected. However, according to 's dissertation in 2013, the object has a much higher albedo of , which greatly reduces its effective diameter to .

Satellite

On 25 October 2002, observations in the far-infrared with the

NICMOS The Near Infrared Camera and Multi-Object Spectrometer (NICMOS) is a scientific instrument for infrared astronomy, installed on the Hubble Space Telescope (HST), operating from 1997 to 1999, and from 2002 to 2008. Images produced by NICMOS contain ...

instrument of the Hubble Space Telescope revealed that is a binary system with a satellite in its orbit. The discovery was announced on 6 October 2005. Johnston's Archive derives a diameter of for the

primary Primary or primaries may refer to: Arts, entertainment, and media Music Groups and labels * Primary (band), from Australia * Primary (musician), hip hop musician and record producer from South Korea * Primary Music, Israeli record label Works * ...

and a diameter of for the secondary, based on a secondary-to-primary diameter ratio of 0.347, for a difference of 1.3 magnitudes between the two objects. The satellite, designated S/2005 (82075) 1, orbits its primary every 10 days (estimated) at an average distance of .

References

External links

Summary data for (82075)
Small Bodies Data Ferret

Robert Johnston, johnstonsarchive.net

Stephen C. Tegler (archived)

Minor Planet Center * {{DEFAULTSORT:2000 YW134 082075 082075 082075 20001226