2518 Rutllant, provisional designation , is a stony Flora
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 kilometers in diameter. It was discovered by Chilean astronomer
Carlos Torres at the
Cerro El Roble Station of the
National Astronomical Observatory in Chile, on 22 March 1974, and named for astronomer
Federico Alcina.
Orbit and classification
''Rutllant'' is a member of the
Flora family
The Flora family (''adj. Florian''; ; also known as the 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 approx ...
, one of the largest groups of stony asteroids in the main-belt. It orbits the Sun in the
inner main-belt at a distance of 1.9–2.7
AU once every 3 years and 6 months (1,281 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 6
° 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 ...
.
A first
precovery
In astronomy, precovery (short for pre-discovery recovery) is the process of finding the image of a celestial object in images or photographic plates predating its discovery, typically for the purpose of calculating a more accurate orbit. This ha ...
was taken at
Goethe Link Observatory in 1954, 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 at Cerro El Roble.
Physical characteristics
''Rutllant'' has been characterized as a stony
S-type asteroid
S-type (stony-type or silicaceous-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 ...
.
Rotational lightcurve
A rotational
lightcurve
In astronomy, a light curve is a graph (discrete mathematics), graph of the Radiance, light intensity of a celestial object or region as a function of time, typically with the magnitude (astronomy), magnitude of light received on the ''y''-axis ...
was obtained by American astronomer
Brian Warner at his Palmer Divide Observatory (), Colorado, in October 2010. The lightcurve gave a well-defined
period of hours with a relatively low brightness variation of 0.12 in
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 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 of 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 ...
, the asteroid has an outstandingly high
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 0.77 with a diameter of 3.2 kilometer,
while the ''Collaborative Asteroid Lightcurve Link'' (CALL) assumes an albedo of 0.24, derived from the Flora family's largest member and namesake, the asteroid
8 Flora
8 Flora is a large, bright main-belt asteroid. It is the innermost ''large'' asteroid: no asteroid closer to the Sun has a diameter above 25 kilometers (20% that of Flora), and not until 20-km 149 Medusa was discovered was an asteroid known to o ...
. Consequently, CALL calculates a much larger diameter of 5.9 kilometer, as the lower the albedo (reflectivity), the larger the body's diameter at a constant absolute magnitude (brightness).
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 in memory of Spanish-born astronomer Federico Alcina (1904–1971), director of the Chilean
National Astronomical Observatory (OAN), and professor of mathematics at
Federico Santa María Technical University.
Alcina was instrumental for the development of Chilean astronomy, and responsible for a number of critical agreements and decisions, such as moving OAN from Lo Espejo to its current location, for the installment of the
Maipú Radio Observatory upon an agreement with
UF, for another agreement with
UChicago,
University of Texas
The University of Texas at Austin (UT Austin, UT, or Texas) is a public research university in Austin, Texas, United States. Founded in 1883, it is the flagship institution of the University of Texas System. With 53,082 students as of fall 2 ...
, and later
AURA — that resulted in the setup of the
CTIO, as well as for an agreement with the former
Soviet Academy of Sciences
The Academy of Sciences of the Soviet Union was the highest scientific institution of the Soviet Union from 1925 to 1991. It united the country's leading scientists and was subordinated directly to the Council of Ministers of the Soviet Union (un ...
that lead to the building of the
Cerro El Roble Station, where this minor planet was discovered.
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 26 March 1986 ().
References
External links
*
Lightcurve plot of 2518 Rutllant Palmer Divide Observatory,
B. D. Warner (2010)
Asteroid Lightcurve Database (LCDB) query form
)
Dictionary of Minor Planet Names Google books
– Observatoire de Genève, Raoul Behrend
– Minor Planet Center
*
*
{{DEFAULTSORT:Rutllant
002518
Discoveries by Carlos Torres (astronomer)
Named minor planets
19740322