751 Faïna (''
prov. designation:'' ''or'' ) is a very large
background asteroid
An asteroid family is a population of asteroids that share similar proper orbital elements, such as semimajor axis, eccentricity, and orbital inclination. The members of the families are thought to be fragments of past asteroid collisions. An ...
from the central regions 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, c ...
, approximately in diameter. It was discovered on 28 April 1913, by Russian astronomer
Grigory Neujmin
Grigory Nikolayevich Neujmin (russian: Григорий Николаевич Неуймин; – 17 December 1946) was a Georgian–Russian astronomer, native of Tbilisi in Georgia, and a discoverer of numerous minor planets as well as 6 periodi ...
at the
Simeiz Observatory
Simeiz Observatory (also spelled Simeis or Simeïs) was an astronomy research observatory until the mid-1950s. It is located on Mount Koshka, Crimea, , by the town of Simeiz.
Part of the Crimean Astrophysical Observatory, it is currently used f ...
on the Crimean peninsula.
The elongated
C-type asteroid
C-type (carbonaceous) asteroids are the most common variety, forming around 75% of known asteroids. They are volatile-rich and distinguished by a very low albedo because their composition includes a large amount of carbon, in addition to rocks ...
(Ch) has a
rotation period of 23.7 hours. It was named after Faina Mikhajlovna Neujmina, colleague and first wife of the discoverer.
Orbit and classification
Located close to the region of the stony
Eunomia family The Eunomia or Eunomian family () is a large asteroid family of S-type asteroids named after the asteroid 15 Eunomia. It is the most prominent family in the intermediate asteroid belt and the 6th-largest family with nearly six thousand known member ...
(),
''Faïna'' is a non-
family
Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...
asteroid of the main belt's
background population when applying the modern synthetic
hierarchical clustering method
An asteroid family is a population of asteroids that share similar proper orbital elements, such as semimajor axis, eccentricity, and orbital inclination. The members of the families are thought to be fragments of past asteroid collisions. An ...
(HCM) by
Nesvorný as well as
Milani Milani (or Milāni) is an Italian surname. Notable people with the surname include:
*Abbas Milani (born 1949), Iranian-American historian and author
*Alfredo Milani (born 1924), Italian motorcycle racer
*Andrea Milani, several people
** Andrea Mila ...
and
Knežević (AstDys).
However, in the 1995 HCM-analysis by
Zappalà,
''Faïna'' is the parent body of the tiny
Faïna family,
which is not recognized by modern analysis. The HCM-method is based on an object's
proper orbital elements
__NOTOC__
The proper orbital elements or proper elements of an orbit are constants of motion of an object in space that remain practically unchanged over an astronomically long timescale. The term is usually used to describe the three quantitie ...
to group asteroids into families.
''Faïna'' orbits the Sun in the
central asteroid belt at a distance of 2.2–2.9
AU once every 4 years and 1 month (1,489 days;
semi-major axis of 2.55 AU). 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 0.15 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 16
° 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 agains ...
.
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
Vienna Observatory
The Vienna Observatory (german: Universitätssternwarte Wien) is an astronomical observatory in Vienna, Austria. It is part of the University of Vienna. The first observatory was built in 1753–1754 on the roof of one of the university buildings ...
on 8 May 2013, or two weeks after its official discovery observation by
Grigory Neujmin
Grigory Nikolayevich Neujmin (russian: Григорий Николаевич Неуймин; – 17 December 1946) was a Georgian–Russian astronomer, native of Tbilisi in Georgia, and a discoverer of numerous minor planets as well as 6 periodi ...
at
Simeiz.
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 ''mino ...
was named after Faina Mikhajlovna Neujmina, the first wife of the discoverer. Astronomer
Lutz Schmadel
Lutz Dieter Schmadel (2 July 1942, in Berlin – 21 October 2016) was a German astronomer and a prolific discoverer of asteroids, who worked at the Astronomisches Rechen-Institut (ARI) of the University of Heidelberg.
His special interest was t ...
compiled this , based on his private communication with "N. S. Samojlova-Yakhontova", as neither the
Minor Planet Circulars nor ''
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 ...
'' give any information about this asteroid's name.
Physical characteristics
In the
Tholen classification
An asteroid spectral type is assigned to asteroids based on their emission spectrum, color, and sometimes albedo. These types are thought to correspond to an asteroid's surface composition. For small bodies that are not internally differentiated ...
, ''Faïna'' is a common, carbonaceous
C-type asteroid
C-type (carbonaceous) asteroids are the most common variety, forming around 75% of known asteroids. They are volatile-rich and distinguished by a very low albedo because their composition includes a large amount of carbon, in addition to rocks ...
, while in the Bus–Binzel
SMASS classification
An asteroid spectral type is assigned to asteroids based on their emission spectrum, color, and sometimes albedo. These types are thought to correspond to an asteroid's surface composition. For small bodies that are not internally differentiat ...
, it is a hydrated carbonaceous Ch-type.
Rotation period
In late 1988, 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 freq ...
of ''Faïna'' was obtained from
photometric observations by Richard Miles at the Manley Observatory near
Chester in northwest England. Lightcurve analysis gave a well-defined
rotation period of hours with a brightness variation of
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 ...
().
Alternative observations by Roberto Crippa, Federico Manzini (2006) as well as by Bruno Christmann (2019) determined a period of + and () hours (or half the period) with an amplitude of and magnitude ().
Diameter and albedo
According to the surveys carried out by the Japanese
Akari satellite, 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 ...
, and the
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 201 ...
mission of 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 201 ...
(WISE), ''Faïna'' measures (), () and () kilometers in diameter and its surface has a low
albedo
Albedo (; ) is the measure of the diffuse reflection of 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 that refl ...
of (), () and (), respectively.
The ''Collaborative Asteroid Lightcurve Link'' adopts the results from IRAS, that is, an albedo of 0.0497 and a diameter of 110.50 kilometers based on an
absolute magnitude
Absolute magnitude () is a measure of the luminosity of a celestial object on an inverse logarithmic astronomical magnitude scale. An object's absolute magnitude is defined to be equal to the apparent magnitude that the object would have if it ...
of 8.66.
The WISE team also published several alternative mean-diameters of (), (), (), () and (), with a corresponding albedo of (), (), (), (), and ().
On 28 March 2007, an
asteroid occultation
An occultation is an event that occurs when one object is hidden from the observer by another object that passes between them. The term is often used in astronomy, but can also refer to any situation in which an object in the foreground blocks ...
of ''Faïna'' gave a best-fit ellipse dimension of () with a quality rating of 2, indicating its irregular, elongated shape. Another occultation on 21 October 2012, gave an ellipse of (). These timed observations are taken when the asteroid passes in front of a distant star.
References
}
External links
Lightcurve Database Query(LCDB), at ''www.minorplanet.info''
Dictionary of Minor Planet Names Google books
– ''
Geneva Observatory
The Geneva Observatory (french: Observatoire de Genève, german: Observatorium von Genf) is an astronomical observatory at Sauverny (CH) in the municipality of Versoix, Canton of Geneva, in Switzerland. It shares its buildings with the astronomy d ...
'',
Raoul Behrend
This is a list of minor-planet discoverers credited by the Minor Planet Center with the discovery of one or several minor planets (such as near-Earth and main-belt asteroids, Jupiter trojans and distant objects). , the discovery of 612,011 num ...
Discovery Circumstances: Numbered Minor Planets (1)-(5000)– Minor Planet Center
*
*
{{DEFAULTSORT:Faina
000751
000751
Discoveries by Grigory Neujmin
Named minor planets
000751
000751
19130428