2227 Otto Struve, provisional designation , is an

asteroid An asteroid is a minor planet—an object larger than a meteoroid that is neither a planet nor an identified comet—that orbits within the Solar System#Inner Solar System, inner Solar System or is co-orbital with Jupiter (Trojan asteroids). As ...

from the inner regions 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 ...

, approximately 4.7 kilometers in diameter. The asteroid was discovered on 13 September 1955, by the

Indiana Asteroid Program The Indiana Asteroid Program was a photographic astronomical survey of asteroids during 1949–1967, at the U.S. Goethe Link Observatory near Brooklyn, Indiana, Brooklyn, Indiana. The program was initiated by Frank K. Edmondson of Indiana Universi ...

Goethe Link Observatory The Goethe Link Observatory, observatory code 760, is an astronomical observatory near Brooklyn, Indiana, United States. It is owned by Indiana University and operated by the Indiana Astronomical Society https://iasindy.org/about.html, which eff ...

near Brooklyn, Indiana, United States. It was named after Russian astronomer

Otto Struve Otto Lyudvigovich Struve (; 12 August 1897 – 6 April 1963) was a Russian-American astronomer of Baltic German origin. Otto was the descendant of famous astronomers of the Struve family; he was the son of Ludwig Struve, grandson of Otto Wilhel ...

Orbit and classification

The asteroid orbits the Sun in the inner main-belt at a distance of 1.8–2.6 AU once every 3 years and 4 months (1,222 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-Centre (geometry), center, in geometry * Eccentricity (g ...

of 0.17 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 reference plane and the orbital plane or axis of direction of the orbiting object. For a satellite orbiting the Eart ...

of 5 ° 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 ...

. It was first identified as at the

Johannesburg Observatory Union Observatory, also known as Transvaal Observatory, Republic Observatory and Johannesburg Observatory ( 078), is a defunct astronomical observatory in Johannesburg, South Africa that operated from 1903 to 1971. It is located on Observatory R ...

in 1935, extending 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 ...

by 20 years prior to its official discovery observation.

Physical characteristics

As of 2016, the asteroid's composition,

rotation period In astronomy, the rotation period or spin period of a celestial object (e.g., star, planet, moon, asteroid) has two definitions. The first one corresponds to the '' sidereal rotation period'' (or ''sidereal day''), i.e., the time that the objec ...

and shape remain unknown. According to the surveys carried out by NASA's

Wide-field Infrared Survey Explorer Wide-field Infrared Survey Explorer (WISE, List of observatory codes, observatory code C51, Explorer 92 and MIDEX-6) was a NASA infrared astronomy Space observatory, space telescope in the Explorers Program launched in December 2009.. . WISE L ...

with its subsequent

NEOWISE Wide-field Infrared Survey Explorer (WISE, observatory code C51, Explorer 92 and MIDEX-6) was a NASA infrared astronomy space telescope in the Explorers Program launched in December 2009.. . WISE discovered thousands of minor planets and nu ...

mission, the asteroid measures 4.7 kilometers in diameter and its surface has an

albedo Albedo ( ; ) is the fraction of sunlight that is Diffuse reflection, diffusely reflected by a body. It is measured on a scale from 0 (corresponding to a black body that absorbs all incident radiation) to 1 (corresponding to a body that reflects ...

of 0.388. Based on its absolute

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 ...

of 13.4, it has an estimated diameter between 5 and 13 kilometers, assuming an

in the range of 0.05 to 0.25. Since most asteroids in the inner main-belt are of a silicaceous rather than of a

carbonaceous Carbonaceous refers to something relating to, containing, or composed of carbon. It is a descriptor used for the attribute of any substance rich in carbon. Particularly, ''carbonaceous hydrocarbons'' are very unsaturated, high- molecular-weight h ...

composition, with higheralbedos, typically around 0.20, the asteroid's diameter might be on the lower end of NASA's published conversion table, as the higher the reflectivity (albedo), the smaller the body's diameter at a constant intrinsic brightness (absolute magnitude).

Naming

The minor planet is named in memory of Russian astronomer

(1897–1963), discoverer of the two asteroids

991 McDonalda 991 McDonalda is a Themistian asteroid. It was discovered by Otto Struve in 1922 at the Yerkes Observatory in Williams Bay, Wisconsin, United States. It is named after the McDonald Observatory McDonald Observatory is an astronomical observatory ...

and 992 Swasey, and last of a remarkable dynasty of astronomers: the

Struve family The Struve family (pronounced in German, in Russian) were a Baltic nobility, Baltic German noble family of Eastphalian origin and originated in Magdeburg, the family produced five generations of astronomers from the 18th to 20th centuries. Membe ...

. His great-grandfather, Wilhelm Struve ''(also see 768 Struveana)'', founded the

Pulkovo Observatory The Pulkovo Astronomical Observatory (), officially named the Central Astronomical Observatory of the Russian Academy of Sciences at Pulkovo, is the principal astronomical observatory of the Russian Academy of Sciences. It is located 19 km south ...

near St. Petersburg in 1839; his grandfather ( Otto Wilhelm), uncle ( Hermann) and father (

Ludwig Ludwig may refer to: People and fictional characters * Ludwig (given name), including a list of people and fictional characters * Ludwig (surname), including a list of people * Ludwig von Koopa, a character in Mario (the game) Arts and entertai ...

) were also distinguished astronomers. Following a period of great privation and misery after World War I, Otto was invited by Edwin B. Frost ''(also see

854 Frostia 854 Frostia is a main-belt asteroid orbiting the Sun. It was discovered in 1916 by Sergei Ivanovich Belyavsky from Simeiz Observatory in Crimea and is named after Edwin Brant Frost, an American astronomer. This asteroid measures approximately i ...

)'' to come to the U.S.

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 until 2018. O ...

in 1921. He started working in spectroscopy and remained a spectroscopist to the end of his days. He succeeded Frost as Yerkes director in 1932 and was the major force responsible for the establishment of the Texan

McDonald Observatory McDonald Observatory is an astronomical observatory located near unincorporated community of Fort Davis in Jeff Davis County, Texas, United States. The facility is located on Mount Locke in the Davis Mountains of West Texas, with additional faci ...

in 1933. Managing editor of the

Astrophysical Journal ''The Astrophysical Journal'' (''ApJ'') is a peer-reviewed scientific journal of astrophysics and astronomy, established in 1895 by American astronomers George Ellery Hale and James Edward Keeler. The journal discontinued its print edition and ...

from 1932 to 1947 and became head of the astronomy department of the University of California in Berkeley in 1950. He received the

Gold Medal of the Royal Astronomical Society The Gold Medal of the Royal Astronomical Society is the highest award given by the Royal Astronomical Society (RAS). The RAS Council have "complete freedom as to the grounds on which it is awarded" and it can be awarded for any reason. Past awar ...

in 1944, and the

Bruce Medal The Catherine Wolfe Bruce Gold Medal is awarded every year by the Astronomical Society of the Pacific for outstanding lifetime contributions to astronomy. It is named after Catherine Wolfe Bruce, an American patroness of astronomy, and was ...

in 1948. The lunar crater '' Struve'' was also named in his honor. 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. Funct ...

on 13 July 1984 ().

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:Otto Struve 002227 002227 Named minor planets 002227 19550913