1027 Aesculapia, provisional designation , is a

Themistian asteroid The Themis family (''adj. Themistian''; ) is a family of carbonaceous asteroids located in the outer portion of the asteroid belt, at a mean distance of 3.13 AU from the Sun. It is one of the largest families with over 4700 known members, and cons ...

from the outer 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 33 kilometers in diameter. It was discovered on 11 November 1923, by Belgian–American astronomer

George Van Biesbroeck George A. Van Biesbroeck (or Georges-Achille Van Biesbroeck, , January 21, 1880 – February 23, 1974) was a Belgian–American astronomer. He worked at observatories in Belgium, Germany and the United States. He specialized in the observation o ...

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 ...

in Williams Bay, Wisconsin, United States. It is named for Aesculapius, the god of medicine in Greek mythology.

Classification and orbit

''Aesculapia'' is a member of the

Themis family The Themis family (''adj. Themistian''; ) is a Asteroid family, family of carbonaceous asteroids located in the Kirkwood gap, outer portion of the asteroid belt, at a mean distance of 3.13 Astronomical Unit, AU from the Sun. It is one of the Asteroi ...

, a dynamical group of

carbonaceous Carbon () is a chemical element with the chemical symbol, symbol C and atomic number 6. It is nonmetallic and tetravalence, tetravalent—its atom making four electrons available to form covalent bond, covalent chemical bonds. It belongs to gro ...

outer-belt asteroids which are known for their nearly coplanar ecliptical orbits. It orbits the Sun at a distance of 2.7–3.6 AU once every 5 years and 7 months (2,044 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 0.13 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 1 ° with respect to the ecliptic. In 1889, it was first identified as at Harvard Observatory's Boyden Station in Arequipa, Peru. 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 at

Heidelberg Heidelberg (; Palatine German language, Palatine German: ''Heidlberg'') is a city in the States of Germany, German state of Baden-Württemberg, situated on the river Neckar in south-west Germany. As of the 2016 census, its population was 159,914 ...

in 1908, when it was identified as , 15 years prior to its official discovery observation at Williams Bay.

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 satellite developed by Japan Aerospace Exploration Agency, in cooperation with institutes of Europe and Korea. It was launched on 21 February 2006, at 21:28 UTC (06:28, 22 February JST) by M-V rocke ...

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, ''Aesculapia'' measures between 31.225 and 38.55 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 ...

between and 0.06 and 0.129. The ''Collaborative Asteroid Lightcurve Link'' (CALL) derives an albedo of 0.075 and a diameter of 32.05 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 10.9. Despite the body's low albedo, CALL classifies ''Aesculapia'' as a S-type rather than a C-type asteroid.

Photometry

In the last 20 years, photometric observations of ''Aesculapia'' gave several 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 ...

s with significantly divergent

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 ...

s. First results obtained by Chester Maleszewski and René Roy were only fragmentary or incorrect (). Photometry 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 ...

and observations by Astronomer Steven Ehlert gave a period of 9.791 and 19.506 hours with a brightness amplitude of 0.09 and 0.19

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 ...

, respectively (). CALL currently adopts a lightcurve obtained by Kylie Hess at Oakley Southern Sky Observatory in March 2015, which gave a period of 13.529 hours and a brightness variation of 0.09 magnitude ().

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 Aesculapius, the Greek and Roman demigod of medicine and healing, son of

Apollo Apollo, grc, Ἀπόλλωνος, Apóllōnos, label=genitive , ; , grc-dor, Ἀπέλλων, Apéllōn, ; grc, Ἀπείλων, Apeílōn, label=Arcadocypriot Greek, ; grc-aeo, Ἄπλουν, Áploun, la, Apollō, la, Apollinis, label= ...

and Coronis, after whom the asteroids

158 Koronis Koronis (minor planet designation: 158 Koronis) is a Asteroid belt, main-belt asteroid that was discovered by Russian astronomer Viktor Knorre on January 4, 1876, from the Berlin observatory. It was the first of his four asteroid discoveries. Th ...

and 1862 Apollo are named, respectively. Naming citation was first mentioned in ''

The Names of the Minor Planets Paul Herget (January 30, 1908 – August 27, 1981) was an American astronomer and director of the Cincinnati Observatory, who established the Minor Planet Center after World War II. Career Herget taught astronomy at the University of Cincinna ...

'' by

Paul Herget Paul Herget (January 30, 1908 – August 27, 1981) was an American astronomer and director of the Cincinnati Observatory, who established the Minor Planet Center after World War II. Career Herget taught astronomy at the University of Cincinna ...

in 1955 ().

Notes

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:Aesculapia 001027 001027 Discoveries by George Van Biesbroeck Named minor planets 19231111