Centaur (constellation)
See also: Centaur (homonymy)
The Centaure is a Constellation of the Southern hemisphere, one of vastest of the sky. It contains a rather considerable number of star S brilliant, 10 of them exceeding the Magnitude connect 3.
History
The constellation of the Centaur belongs to the 48 constellations indexed by Ptolémée in its Almageste . It was already mentioned by Eudoxe (4th front century J. - C.) and Aratos de Soles (3rd front century J. - C.)In the Greek Mythology, the Centaur (creature semi-man, the semi-horse) that this constellation indicates would be Chiron, wisest of the centaurs, tutor of Jason and Hercules. Certain sources allot also the to him Sagittarius, although Pholos or Crotos is more often associated with this last.
Observation of the sky
The Centaur is a splendid vision of the southern sky, by its number of brilliant stars, but its general form is not very easy to trace. It is quite visible only for the observers located sufficiently at the south, in practice at least in the Tropics.; Localization of the constellation The centaur is on the alignment which passes by α Bootis (Arcturus) and α Virginis (Spica): this alignment touches the Centaur on ι (the elbow) and γ (the croup) before touching the Croix of the South. Alpha of the centaur is with 60°S, that is to say ~50° more in the South that α Virginis.
In addition, the Centaur is on the Milky Way, between two other very rich constellations: the Scorpion in the east, and the Ship Argo in the east.
The proximity of the Croix of the South makes it possible to direct NORTH-SOUTH alignments easily.
; Form constellation The first two visible stars are RigilKenttaurus (α Cen) and Hadar (β Cen), enough close relations (~5°) one of the other, and very brilliant (mag 0). In their alignment towards the West, one then easily locates the Croix of the South.
The " part; chevaline" centaur spans the cross. It is marked in particular by γ Cen, brilliant star located in the axis of the Croix of the South. ε Cen, the star located appreciably between γ and α, mark the junction of the front legs. ζ Cen is the third star which closes the triangle of the " part; chevaline" , in the north of β. The legs back of the Centaur are on the level of the Croix of the South, between this constellation and the beginning of the Navire Argo.
The head of the Centaur is marked by θ Cen, the brilliant star located 25° at the North of α and β, at the end of a vague alignment and guy-zagant, kind of " W" very flattens, formed by β, ε, ζ, ν and θ.
Principal stars
See also: List of stars of the Centaur
α Centauri
α Centauri is the stellar system nearest to our Solar system. α Centauri With, also named Rigel Kentaurus (the foot of the Arab Centaur in ) or Toliman , is the third most luminous star of the sky (Magnitude connects -0,01). It forms a binary system with her partner, α Centauri B. A third star nellement seems related Gravitation to the couple: Proxima Centauri is a Naine invisible red with the naked eye but of which the position in the system d'α Centauri makes of it star nearest to the Ground, distant from 4,22 light-years.
Other stars
Hadar, or Agéna, (β Centauri) is a blue Géante magnitude connect 0,6.The Centaur also contains BPM 37093, a dead star which would be made up exclusively of Carbone Cristal flax, gigantic a Diamant.
Celestial objects
ω Cen is not a star, but the globular Amas more the brilliance of the sky.The Centaur also shelters the Nébuleuse Boomerang, the coldest celestial object ever measured (1 K).
See too
- List of stars of the Centaur