1983 Bok ( ''prov. designation'': ) is a dark background asteroid from the central region of the

asteroid belt The asteroid belt is a torus-shaped region in the Solar System, centered on the Sun and roughly spanning the space between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies called asteroids ...

. It was discovered on 9 June 1975, by American astronomer Elizabeth Roemer at the Catalina Station of the UA's Steward Observatory in Tucson, Arizona, and named for

Bart Bok Bartholomeus Jan "Bart" Bok (April 28, 1906 – August 5, 1983) was a Dutch-American astronomer, teacher, and lecturer. He is best known for his work on the structure and evolution of the Milky Way galaxy, and for the discovery of Bok globules, w ...

and Priscilla Fairfield Bok. The carbonaceous C-type asteroid has a rotation period of 10.7 hours and measures approximately in diameter.

Classification and orbit

''Bok'' orbits the Sun in the central main-belt at a distance of 2.4–2.9 AU once every 4 years and 3 months (1,550 days). Its orbit has an eccentricity of 0.10 and an inclination of 9 ° with respect to the

ecliptic The ecliptic or ecliptic plane is the orbital plane of Earth's orbit, Earth around the Sun. It was a central concept in a number of ancient sciences, providing the framework for key measurements in astronomy, astrology and calendar-making. Fr ...

. The first observation was taken at the Argentinian La Plata Astronomical Observatory in 1950, extending the asteroid's observation arc by 25 years prior to its discovery.

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 ''minor ...

was named after the astronomer couple

(1906–1983) and Priscilla Fairfield Bok (1896–1975), in recognition for their contribution to astrometry of

small Solar System bodies A small Solar System body (SSSB) is an object in the Solar System that is neither a planet, a dwarf planet, nor a natural satellite. The term was first IAU definition of planet, defined in 2006 by the International Astronomical Union (IAU) as fo ...

. Both astronomers studied the structure of the southern Milky Way and fostered astronomy in the Southern Hemisphere. ''Bok'' was the first numbered discovery made with the Stewart Observatory's 90-inch Bok Telescope. The body's name was proposed by the discovering astronomer and by Alan C. Gilmore from New Zealand. The official was published by the Minor Planet Center on 18 April 1977 ().

Physical characteristics

''Bok'' has been characterized as a C-type asteroid. In October 2014, the first rotational

lightcurve In astronomy, a light curve is a graph (discrete mathematics), graph of the Radiance, light intensity of a celestial object or region as a function of time, typically with the magnitude (astronomy), magnitude of light received on the ''y''-axis ...

for this body was obtained by Italian astronomer Giovanni Battitsa Casalnuovo at the Eurac Observatory () in Bolzano, Italy. Lightcurve analysis gave a well-defined rotation period of hours with a relatively high brightness variation of 0.46 magnitude (). The Italian astronomer also calculated an albedo of 0.06 for its surface and a diameter of kilometers, in agreement with the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer which gave a diameter of 15.7 kilometers and an albedo of 0.034. The ''Collaborative Asteroid Lightcurve Link'' assumes an albedo of 0.10, a compromise value between the stony (0.20) and carbonaceous (0.057) asteroids with a semi-major axis between 2.6 and 2.7 AU, and consequently calculates a much smaller diameter of 10.08 kilometers using an absolute magnitude of 13.1.

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:Bok 001983 Discoveries by Elizabeth Roemer Named minor planets 19750609