9223 Leifandersson, provisional designation , is a background asteroid from the inner 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 4.5 kilometers in diameter. It was discovered on 18 December 1995, by astronomers of the
Spacewatch
The Spacewatch Project is an astronomical survey that specializes in the study of minor planets, including various types of asteroids and comets at University of Arizona telescopes on Kitt Peak near Tucson, Arizona, in the United States. The Spa ...
program at
Kitt Peak National Observatory
The Kitt Peak National Observatory (KPNO) is a United States astronomical observatory located on Kitt Peak of the Quinlan Mountains in the Arizona-Sonoran Desert on the Tohono Oʼodham Nation, west-southwest of Tucson, Arizona. With more than ...
in Arizona, United States. The asteroid was named in memory of Swedish astronomer
Leif Erland Andersson
Leif Erland Andersson (4 November 1943 – 4 May 1979) was a Swedish astronomer.
Early life
Andersson had been a child prodigy who won the Swedish television quiz show ''10.000-kronorsfrågan'' ("The 10,000 Kronor Question") twice, the first ...
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 ...
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 ...
to its
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 ...
. It has also been classified as a member of the
Flora family
The Flora family (''adj. Florian''; ; also known as ''Ariadne family'') is a prominent family of stony asteroids located in the inner region of the asteroid belt. It is one of the largest families with more than 13,000 known members, or approxi ...
(), a giant asteroid family and the largest family of stony asteroids in the main-belt. It orbits the Sun in the inner asteroid belt at a distance of 2.1–2.5 AU once every 3 years and 6 months (1,275 days; semi-major axis of 2.30 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 0.07 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 ...
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 with its first observation as at Goethe Link Observatory in August 1948, or more than 47 years prior to its official discovery observation at Kitt Peak.
Physical characteristics
''Leifandersson'' is an assumed stony
S-type asteroid
S-type asteroids are asteroids with a spectral type that is indicative of a siliceous (i.e. stony) mineralogical composition, hence the name. They have relatively high density. Approximately 17% of asteroids are of this type, making it the secon ...
.
Rotation period
In February 2011, 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 ''Leifandersson'' was obtained from photometric observations by astronomers at the Palomar Transient Factory in California. Lightcurve analysis gave a rotation period of 3.758 hours with a brightness amplitude of 0.33
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 survey carried out by 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 ...
, ''Leifandersson'' measures 4.498 kilometers in diameter and its surface has an
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 0.3810. The ''Collaborative Asteroid Lightcurve Link'' assumes an albedo of 0.24 – derived from 8 Flora, the parent body of the Flora family – and calculates a diameter of 4.64 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 13.83.
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 Swedish astronomer
Leif Erland Andersson
Leif Erland Andersson (4 November 1943 – 4 May 1979) was a Swedish astronomer.
Early life
Andersson had been a child prodigy who won the Swedish television quiz show ''10.000-kronorsfrågan'' ("The 10,000 Kronor Question") twice, the first ...
(1943–1979), who calculated the first observable transits of
Pluto
Pluto (minor-planet designation: 134340 Pluto) is a dwarf planet in the Kuiper belt, a ring of bodies beyond the orbit of Neptune. It is the ninth-largest and tenth-most-massive known object to directly orbit the Sun. It is the largest ...
lunar craters
Lunar craters are impact craters on Earth's Moon. The Moon's surface has many craters, all of which were formed by impacts. The International Astronomical Union currently recognizes 9,137 craters, of which 1,675 have been dated.
History
The wor ...
. The approved naming citation was published by the Minor Planet Center on 24 January 2000 (). The lunar crater ''
Andersson
Andersson (previously Andjersson) is a Swedish language surname, a form of the surname Anderson. ''Andersson'' is, if several spelling variants are included, the most common surname in Sweden.