1749 Telamon is a dark
Jupiter Trojan
The Jupiter trojans, commonly called trojan asteroids or simply trojans, are a large group of asteroids that share the planet Jupiter's orbit around the Sun. Relative to Jupiter, each trojan librates around one of Jupiter's stable Lagrange poin ...
from the
Greek camp
This is a list of Jupiter trojans that lie in the Greek camp, an elongated curved region around the leading Lagrangian point (), 60 ° ahead of Jupiter in its orbit.
All the asteroids at Jupiter's point have names corresponding to participants ...
, approximately in diameter. It was discovered by German astronomer
Karl Reinmuth
Karl Wilhelm Reinmuth (4 April 1892 in Heidelberg – 6 May 1979 in Heidelberg) was a German astronomer and a prolific discoverer of 395 minor planets.
Scientific career
From 1912 to 1957, Reinmuth was working as an astronomer at the Lande ...
at the
Heidelberg Observatory
Heidelberg (; Palatine German: ') is a city in the German state of Baden-Württemberg, situated on the river Neckar in south-west Germany. As of the 2016 census, its population was 159,914, of which roughly a quarter consisted of students.
...
on 23 September 1949,
and named after
Telamon from Greek mythology.
The
D-type asteroid
D-type asteroids have a very low albedo and a featureless reddish Asteroid spectral types, spectrum. It has been suggested that they have a composition of organic-rich silicates, carbon and anhydrous silicates, possibly with water ice in their inte ...
is the principal body of the proposed
Telamon family and belongs to the
60 largest Jupiter trojans. It has a
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 ...
of 17.0 hours and possibly a spherical shape.
Classification and orbit
''Telamon'' is a dark Jovian
asteroid
An asteroid is a minor planet of the inner Solar System. Sizes and shapes of asteroids vary significantly, ranging from 1-meter rocks to a dwarf planet almost 1000 km in diameter; they are rocky, metallic or icy bodies with no atmosphere.
...
orbiting in the leading Greek camp at Jupiter's
Lagrangian point
In celestial mechanics, the Lagrange points (; also Lagrangian points or libration points) are points of equilibrium for small-mass objects under the influence of two massive orbiting bodies. Mathematically, this involves the solution of th ...
, 60
° ahead of the Gas Giant's orbit in a
1:1 resonance ''(see
Trojans in astronomy
In astronomy, a trojan is a small celestial body (mostly asteroids) that shares the orbit of a larger body, remaining in a stable orbit approximately 60° ahead of or behind the main body near one of its Lagrangian points and . Trojans can sha ...
)''.
It orbits the Sun at a distance of 4.6–5.7
AU once every 11 years and 8 months (4,268 days;
semi-major axis
In geometry, the major axis of an ellipse is its longest diameter: a line segment that runs through the center and both foci, with ends at the two most widely separated points of the perimeter. The semi-major axis (major semiaxis) is the long ...
of 5.15 AU). Its orbit has an
eccentricity of 0.11 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 6
° with respect to the
ecliptic.
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 with its first observation as ' at
Turku Observatory
Turku ( ; ; sv, Åbo, ) is a city and former capital on the southwest coast of Finland at the mouth of the Aura River, in the region of Finland Proper (''Varsinais-Suomi'') and the former Turku and Pori Province (''Turun ja Porin lääni''; ...
in January 1941, more than 8 years prior to its official discovery observation at Heidelberg.
Telamon family
Fernando Roig and
Ricardo Gil-Hutton
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 numb ...
identified ''Telamon'' as the principal body of a small Jovian
asteroid family
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 a ...
, using the
hierarchical clustering method (HCM), which looks for groupings of neighboring asteroids based on the smallest distances between them in the
proper orbital element
__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 ...
space. According to the astronomers, the
Telamon family belongs to the larger
Menelaus clan
1647 Menelaus is a mid-sized Jupiter trojan from the Greek camp, approximately in diameter. It was discovered on 23 June 1957 by American astronomer Seth Nicholson at the Palomar Observatory in California, and later named after the Spartan King ...
, an aggregation of Jupiter trojans which is composed of several families, similar to the
Flora family in the inner
asteroid belt.
However this family is not included in
David Nesvorný
David (; , "beloved one") (traditional spelling), , ''Dāwūd''; grc-koi, Δαυΐδ, Dauíd; la, Davidus, David; gez , ዳዊት, ''Dawit''; xcl, Դաւիթ, ''Dawitʿ''; cu, Давíдъ, ''Davidŭ''; possibly meaning "beloved one". w ...
HCM-analysis from 2014.
Instead, ''Telamon'' is listed as a non-family asteroid of the
Jovian background population on the Asteroids Dynamic Site (AstDyS) which based on another analysis by Milani and Knežević.
Physical characteristics
''Telamon'' is a dark
D-type asteroid
D-type asteroids have a very low albedo and a featureless reddish Asteroid spectral types, spectrum. It has been suggested that they have a composition of organic-rich silicates, carbon and anhydrous silicates, possibly with water ice in their inte ...
according to the
SDSS-based taxonomy and the surveys conducted by
SMASS (Xu) and
Pan-STARRS.
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 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 mission, ''Telamon'' measures between 64.90 and 81.06 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 0.046 and 0.078.
The ''Collaborative Asteroid Lightcurve Link'' derives an albedo of 0.0469 and a diameter of 80.91 kilometers based on 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 9.4.
Lightcurves
Photometric observations of ''Telamon'' by
Stefano Mottola
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 numb ...
from August 1995 were used to build a
lightcurve rendering a
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 ...
of 11.2 hours with a brightness variation of in
magnitude ().
In October 2010, another observation by
Robert Stephens
Sir Robert Graham Stephens (14 July 193112 November 1995) was a leading English actor in the early years of Britain's Royal National Theatre. He was one of the most respected actors of his generation and was at one time regarded as the natur ...
at the Goat Mountain Astronomical Research Station in California gave a period of 16.975 hours ().
In August 2017, observations by the
K2 mission of the ''
Kepler
Johannes Kepler (; ; 27 December 1571 – 15 November 1630) was a German astronomer, mathematician, astrologer, natural philosopher and writer on music. He is a key figure in the 17th-century Scientific Revolution, best known for his laws o ...
'' spacecraft during Campaign 6 gave two periods of 11.331 and 22.613 hours with an amplitude of 0.06 and 0.07 magnitude, respectively ().
The body is possibly of spherical shape as all lightcurves measured a very small variation in 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 by the discoverer after
Telamon, from Greek mythology, who was an
argonaut searching for the Golden Fleece, and father of Ajax and Teucer, after whom the minor planets
1404 Ajax and
2797 Teucer
2797 Teucer is a large Jupiter trojan from the Greek camp, approximately in diameter. It was discovered on 4 June 1981, by American astronomer Edward Bowell at the Anderson Mesa Station near Flagstaff, Arizona, in the United States. The dark D- ...
are named.
Telamon banished his son
Teucer (as he had been banished by his own father) when he returned home from the Trojan war without the remains of his brother.
The official 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.
Function
...
on 15 February 1970 ().
References
External links
Asteroid Lightcurve Database (LCDB) query form
)
Dictionary of Minor Planet Names Google books
– Minor Planet Center
*
*
{{DEFAULTSORT:Telamon
001749
Discoveries by Karl Wilhelm Reinmuth
Named minor planets
19490923