6349 Acapulco, provisional designation , is a dark Adeonian

asteroid An asteroid is a minor planet of the inner Solar System. Sizes and shapes of asteroids vary significantly, ranging from 1-meter rocks to a dwarf planet almost 1000 km in diameter; they are rocky, metallic or icy bodies with no atmosphere. ...

from the middle region of the

asteroid belt The asteroid belt is a torus-shaped region in the Solar System, located roughly between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies, of many sizes, but much smaller than planets, called ...

, approximately 22 kilometers in diameter. The asteroid was discovered on 8 February 1995, by Japanese astronomer

Masahiro Koishikawa was a Japan, Japanese astronomer. He studied both major and minor planets, and discovered multiple asteroids. Koishikawa was a staff member of the Sendai Astronomical Observatory frin 1972. His research was based out of the Sendai's Ayashi (L ...

at the Ayashi Station () of the Sendai Astronomical Observatory in the Tōhoku region of Japan. It was named for the Mexican city of

Acapulco Acapulco de Juárez (), commonly called Acapulco ( , also , nah, Acapolco), is a city and major seaport in the state of Guerrero on the Pacific Coast of Mexico, south of Mexico City. Acapulco is located on a deep, semicircular bay and has bee ...

Orbit and classification

''Acapulco'' is a member of the

Adeona family The Adeona or Adeonian family () is a large asteroid family that formed from the parent body 145 Adeona. Its spectral type is that of a carbonaceous C-type, with currently 2,236 asteroids identified as family members. Based upon simulation ...

(), a large

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

of carbonaceous asteroids. It orbits the Sun in the

central Central is an adjective usually referring to being in the center of some place or (mathematical) object. Central may also refer to: Directions and generalised locations * Central Africa, a region in the centre of Africa continent, also known as ...

main-belt at a distance of 2.3–3.0 AU once every 4 years and 4 months (1,590 days). Its orbit has an

eccentricity Eccentricity or eccentric may refer to: * Eccentricity (behavior), odd behavior on the part of a person, as opposed to being "normal" Mathematics, science and technology Mathematics * Off-center, in geometry * Eccentricity (graph theory) of a v ...

of 0.14 and an

inclination Orbital inclination measures the tilt of an object's orbit around a celestial body. It is expressed as the angle between a Plane of reference, reference plane and the orbital plane or Axis of rotation, axis of direction of the orbiting object ...

of 11 ° with respect to the

ecliptic The ecliptic or ecliptic plane is the orbital plane of the Earth around the Sun. From the perspective of an observer on Earth, the Sun's movement around the celestial sphere over the course of a year traces out a path along the ecliptic again ...

. In March 1947, it was first identified as at

Yerkes Observatory Yerkes Observatory ( ) is an astronomical observatory located in Williams Bay, Wisconsin, United States. The observatory was operated by the University of Chicago Department of Astronomy and Astrophysics from its founding in 1897 to 2018. Owne ...

. The body's

observation arc In observational astronomy, the observation arc (or arc length) of a Solar System body is the time period between its earliest and latest observations, used for tracing the body's path. It is usually given in days or years. The term is mostly use ...

begins 42 years prior to its official discovery observation at Ayashi, with a

precovery In astronomy, precovery (short for pre-discovery recovery) is the process of finding the image of an object in images or photographic plates predating its discovery, typically for the purpose of calculating a more accurate orbit. This happens mos ...

taken at

Palomar Observatory Palomar Observatory is an astronomical research observatory in San Diego County, California, United States, in the Palomar Mountain Range. It is owned and operated by the California Institute of Technology (Caltech). Research time at the observat ...

in 1953.

Physical characteristics

Lightcurves

A rotational

lightcurve In astronomy, a light curve is a graph of light intensity of a celestial object or region as a function of time, typically with the magnitude of light received on the y axis and with time on the x axis. The light is usually in a particular frequ ...

of ''Acapulco'' was obtained from photometric observations made at the

Palomar Transient Factory The Palomar Transient Factory (PTF, obs. code: I41), was an astronomical survey using a wide-field survey camera designed to search for optical transient and variable sources such as variable stars, supernovae, asteroids and comets. The projec ...

in September 2010. Lightcurve analysis gave a

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 hours with a brightness variation of 0.18

magnitude Magnitude may refer to: Mathematics *Euclidean vector, a quantity defined by both its magnitude and its direction *Magnitude (mathematics), the relative size of an object *Norm (mathematics), a term for the size or length of a vector *Order of ...

().

Diameter and albedo

According to the surveys carried out by the Infrared Astronomical Satellite

IRAS The Infrared Astronomical Satellite (Dutch: ''Infrarood Astronomische Satelliet'') (IRAS) was the first space telescope to perform a survey of the entire night sky at infrared wavelengths. Launched on 25 January 1983, its mission lasted ten mo ...

, the Japanese

Akari Akari (ASTRO-F) was an infrared astronomy Infrared astronomy is a sub-discipline of astronomy which specializes in the observation and analysis of astronomical objects using infrared (IR) radiation. The wavelength of infrared light ranges f ...

satellite, and NASA's

Wide-field Infrared Survey Explorer Wide-field Infrared Survey Explorer (WISE, observatory code C51, Explorer 92 and SMEX-6) is a NASA infrared astronomy space telescope in the Explorers Program. It was launched in December 2009, and placed in hibernation mode in February 2011, ...

with its subsequent

NEOWISE Wide-field Infrared Survey Explorer (WISE, observatory code C51, Explorer 92 and SMEX-6) is a NASA infrared astronomy space telescope in the Explorers Program. It was launched in December 2009, and placed in hibernation mode in February 2011, ...

mission, ''Acapulco'' measures between 14.66 and 23.02 kilometers in diameter, and its surface has an

albedo Albedo (; ) is the measure of the diffuse reflection of sunlight, solar radiation out of the total solar radiation and measured on a scale from 0, corresponding to a black body that absorbs all incident radiation, to 1, corresponding to a body ...

in the range of 0.037 to 0.10. The ''Collaborative Asteroid Lightcurve Link'' assumes an albedo of 0.10 and calculates a smaller diameter of 12.35 kilometers with an

absolute magnitude Absolute magnitude () is a measure of the luminosity of a celestial object on an inverse Logarithmic scale, logarithmic Magnitude (astronomy), astronomical magnitude scale. An object's absolute magnitude is defined to be equal to the apparent mag ...

of 12.66.

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 for the Mexican city of

, known for its major seaport, which is considered to be among the most beautiful ones in the world. Since 1973, Acapulco is the

sister city A sister city or a twin town relationship is a form of legal or social agreement between two geographically and politically distinct localities for the purpose of promoting cultural and commercial ties. While there are early examples of inter ...

of the Japanese city of

Sendai is the capital Cities of Japan, city of Miyagi Prefecture, the largest city in the Tōhoku region. , the city had a population of 1,091,407 in 525,828 households, and is one of Japan's 20 Cities designated by government ordinance of Japan, desig ...

, where the discovering observatory is located, and after which the minor planet 3133 Sendai is named.

Hasekura Tsunenaga was a kirishitan Japanese samurai and retainer of Date Masamune, the daimyō of Sendai. He was of Japanese imperial descent with ancestral ties to Emperor Kanmu. Other names include Philip Francis Faxicura, Felipe Francisco Faxicura, and Phi ...

(1571–1622) – retainer of

Date Masamune was a regional ruler of Japan's Azuchi–Momoyama period through early Edo period. Heir to a long line of powerful ''daimyō'' in the Tōhoku region, he went on to found the modern-day city of Sendai. An outstanding tactician, he was made all ...

, who founded the city of Sendai – stopped by at Acapulco on his diplomatic mission to Rome. The official 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 2 February 1999 .

References

External links

Asteroid Lightcurve Database (LCDB)
query form

)
Dictionary of Minor Planet Names
Google books

– Observatoire de Genève, Raoul Behrend

– Minor Planet Center * * {{DEFAULTSORT:Acapulco 006349 Discoveries by Masahiro Koishikawa Named minor planets 19950208