The point in the → Galactic plane that lies directly opposite the → Galactic center. It lies in → Auriga at approximately R.A. 5h 46m, Dec. +28° 56'; the nearest bright star to it is → Alnath in → Taurus.
Anticenter, from → anti- + → center.
The point on an elliptic orbit at the greatest distance from the principal focus or center of attraction.
Apocenter, from → apo- + → center.
Apâmarkaz, apâkayân, from apâ-, → apo-, + markaz or kayân, → center.
The center of mass of a system of bodies.
From Gk. barus "heavy," → bar, + → center.
Gerânigâh, from gerâni "weight;" cognate with Gk. barus, → bar, + gâh "place."
1) markaz (#), kayân (#); 2) markazidan
Fr.: 1) centre; 2) centrer
1) The point that is equidistant from all the points on a circle or sphere.
M.E. centre, from O.Fr. centre, from L. centrum "center," originally fixed point of the two points of a compass, from Gk. kentron "sharp point, goad," from kentein "stitch," from PIE *kent- "to prick."
Markaz "center," from Ar.; kayân, Mod.Pers. "the point made by the compasses, that is the center of a circle" [Dehxodâ]; markazidan, infinitive from markaz, → center, + -idan infinitive suffix.
center of attraction
Fr.: centre d'attraction
A point toward which a force on a body is always directed.
→ center; → attraction.
center of gravity
Fr.: centre de gravité
A fixed point in a body through which the resultant force of gravitational attraction acts. Same as → center of mass, → center of inertia, → centroid.
Gerânigâh, from gerâni→ gravity + -gâh "place."
center of inertia
Fr.: centre d'inertie
Same as → center of gravity, → center of mass, → centroid.
center of mass
Fr.: centre de masse
Same as → center of gravity, → center of inertia, → centroid, and → barycenter.
Fr.: longueur d'onde centrale
Center of a filter passband measured at 50% of peak transmittance.
→ center; → wavelength.
Fr.: centre du cercle circonscrit d'un triangle
In a triangle, the point where the perpendicular bisectors of the triangle's sides converge.
The center of an → excircle.
Fr.: anticentre galactique
The point in the → Galactic plane that lies directly opposite the → Galactic center. It lies in the constellation → Auriga at approximately R.A. 05h 46m, Dec. +28° 56'.
→ galactic; → anticenter.
markaz-e kahkešân (#)
Fr.: centre galactique
1) The rotational center of the → Milky Way galaxy located
in the direction of the → Sagittarius constellation at a
distance of 7.62 ± 0.32 kpc (2005, ApJ 628, 246). Its equatorial coordinates
(J2000 epoch) are: R.A. 17h45m40.04s, Dec. -29° 00' 28.1''.
The Sun orbits around the Galactic center once every 200 million years
at a speed of 220 km per second. It is believed that
there is a → supermassive black hole at the
Galactic center cluster
xuše-ye markaz-e kahkešân
Fr.: amas du centre galactique
One of the three massive clusters located toward the → Galactic center: → Quintuplet cluster, → Arches cluster, → Central cluster. Heavily extinguished by the presence of dust clouds and only accessible at infrared (and longer) wavelengths or in X-rays, each of these clusters has a population of more than a hundred → massive stars. The three clusters are similar in most respects, each containing about 104 solar masses in stars. The Arches cluster is younger than the two others.
Fr.: centre de guidage
In the → epicyclic theory of → galactic rotation, the center of the → epicycle.
markaz-e nuri (#)
Fr.: centre optique
Of a thin lens, a point situated at the geometrical center of the lens, through which an incident ray passes without being deviated.
Of a triangle, the point where the three → altitudes of the → triangle converge.
The point in the orbit of one component of a binary system which is closest to the center of mass of the system; opposite of → apocenter.
Fr.: centre de plaque
The celestial coordinates of the center of the field of an astronomical photographic plate.
Strasbourg Astronomical Data Center (CDS)
Fr.: Centre de Données astronomiques de Strasbourg (CDS)
A data center dedicated to the collection and worldwide distribution of astronomical data and related information. It is located at the Strasbourg Astronomical Observatory, France. The CDS has several goals, mainly: collecting all of the useful information regarding astronomical objects in computerized form, including observational data produced by observatories on the ground or in space; upgrading these data by critical evaluations and comparisons; and distributing the results to the astronomical community. Currently the CDS services include: → SIMBAD, Aladin interactive sky atlas, and VizieR catalogues.
CDS, short for Centre de Données astronomiques de Strasbourg.