2483 Guinevere is a dark and elongated

Hilda asteroid The Hilda asteroids (adj. ''Hildian'') are a dynamical group of more than 5,000 asteroids located beyond the asteroid belt but within Jupiter's orbit, in a 3:2 orbital resonance with Jupiter. The namesake is the asteroid 153 Hilda. Hildas move i ...

from the outermost regions of the asteroid belt, approximately in diameter. The asteroid was discovered on 17 August 1928, by German astronomer

Max Wolf Maximilian Franz Joseph Cornelius Wolf (21 June 1863 – 3 October 1932) was a German astronomer and a pioneer in the field of astrophotography. He was the chairman of astronomy at the University of Heidelberg and director of the Heidelberg-K� ...

Heidelberg Observatory Heidelberg (; Palatine German: ') is a city in the German state of Baden-Württemberg, situated on the river Neckar in south-west Germany. As of the 2016 census, its population was 159,914, of which roughly a quarter consisted of students. ...

in southwest Germany and given the

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 The provisional designation is usually superseded by a permanent designation once a reliable orbit has been calcu ...

. In the 1980s, it was named after King Arthur's wife

Guinevere Guinevere ( ; cy, Gwenhwyfar ; br, Gwenivar, kw, Gwynnever), also often written in Modern English as Guenevere or Guenever, was, according to Arthurian legend, an early-medieval queen of Great Britain and the wife of King Arthur. First ment ...

Classification and orbit

Hildian asteroid

Located in the outermost part of the main-belt, ''Guinevere'' is a member of the

Hilda family The Hilda asteroids (adj. ''Hildian'') are a dynamical group of more than 5,000 asteroids located beyond the asteroid belt but within Jupiter's orbit, in a 3:2 orbital resonance with Jupiter. The namesake is the asteroid 153 Hilda. Hildas move i ...

, a large group of asteroids that are thought to have originated from the

Kuiper belt The Kuiper belt () is a circumstellar disc in the outer Solar System, extending from the orbit of Neptune at 30 astronomical units (AU) to approximately 50 AU from the Sun. It is similar to the asteroid belt, but is far larger—20 times ...

. They orbit in a 3:2 orbital resonance with the gas giant Jupiter, meaning that for every 2 orbits Jupiter completes around the Sun, a Hildian asteroid will complete 3 orbits. Based on a numerical integration, ''Guinevere'' is the Hilda asteroid with the greatest chance of impacting with another asteroid. About 74% of the impact risk occurs when Guinevere is relatively close to perihelion and approaches the main-belt asteroids.

Orbit

''Guinevere'' orbits the Sun at a distance of 2.9–5.1 AU once every 7 years and 11 months (2,890 days). Its orbit has an eccentricity of 0.28 and an inclination of 5 ° with respect to the ecliptic. In November 1921, it was first identified as at Bergedorf Observatory in Hamburg, Germany. The body's observation arc begins two nights after its official discovery observation at Heidelberg in August 1928.

Naming

This minor planet was named after

, the wife of

King Arthur King Arthur ( cy, Brenin Arthur, kw, Arthur Gernow, br, Roue Arzhur) is a legendary king of Britain, and a central figure in the medieval literary tradition known as the Matter of Britain. In the earliest traditions, Arthur appears as a ...

and the lover of

Lancelot Lancelot du Lac (French for Lancelot of the Lake), also written as Launcelot and other variants (such as early German ''Lanzelet'', early French ''Lanselos'', early Welsh ''Lanslod Lak'', Italian ''Lancillotto'', Spanish ''Lanzarote del Lago' ...

in Arthurian legend, after whom the minor planets and are named. This affair lead to civil war between King Arthur and his chief knight, who rescued Guinevere from burning at the stake, and initiated the downfall of Arthur's idyllic kingdom. The name was suggested by Frederick Pilcher and the proposal was submitted by Edward Bowell, who also made the object's key identification. The approved naming citation was published 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 24 July 1983 ().

Physical characteristics

Lightcurves

During a survey of Hilda asteroids in the 1990s, a rotational lightcurve of ''Guinevere'' was obtained from photometric observations by an international collaboration of Swedish, German and Italian astronomers. Lightcurve analysis gave a well-defined

rotation period The rotation period of a celestial object (e.g., star, gas giant, planet, moon, asteroid) may refer to its sidereal rotation period, i.e. the time that the object takes to complete a single revolution around its axis of rotation relative to the ...

of 14.733 hours with a brightness variation of 1.38 magnitude (). ''Guinevere'' is a high-amplitude Hilda. A high brightness amplitude typically indicates that the body is elongated and has a non-

spheroidal A spheroid, also known as an ellipsoid of revolution or rotational ellipsoid, is a quadric surface obtained by rotating an ellipse about one of its principal axes; in other words, an ellipsoid with two equal semi-diameters. A spheroid has circ ...

shape. Thermal emission measurements from the Wide-field Infrared Survey Explorer (WISE) gave an even higher amplitude of 1.53 magnitude. In October 2016, another lightcurve of ''Guinevere'' was obtained at the Center for Solar System Studies (CS3), Landers, in the Southern California desert, during a photometric survey conducted by American astronomers Dan Coley,

Robert Stephens Sir Robert Graham Stephens (14 July 193112 November 1995) was a leading English actor in the early years of Britain's Royal National Theatre. He was one of the most respected actors of his generation and was at one time regarded as the natur ...

and Brian Warner (). It showed a period of 14.730 hours with an amplitude of 0.89 magnitude (). A 2016-published lightcurve, using modeled photometric data from the Lowell Photometric Database (LPD), gave a concurring period of 14.73081 hours (), as well as two spin axis of (19.0°, 70.0°) and (194.0°, 59.0°) in ecliptic coordinates (λ, β).

Diameter and albedo

According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite, and the NEOWISE mission of NASA's WISE spacecraft, ''Guinevere'' measures between 35.687 and 44.17 kilometers in diameter and its surface has an albedo between 0.0433 and 0.067. The ''Collaborative Asteroid Lightcurve Link'' agrees with IRAS and derives an albedo of 0.0396 and a diameter of 44.14 kilometers based on an absolute magnitude of 10.9.

Notes

References

External links

Lightcurve Database Query
(LCDB), at ''www.minorplanet.info''
Dictionary of Minor Planet Names
Google books

– ''Geneva Observatory'', Raoul Behrend
Discovery Circumstances: Numbered Minor Planets (1)-(5000)
– Minor Planet Center * * {{DEFAULTSORT:Guinevere 002483 Discoveries by Max Wolf Named minor planets 19280817