Centaurus

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For other uses, see Centaurus (disambiguation).

Centaurus
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Abbreviation	Cen
Genitive	Centauri
Symbology	the Centaur
Right ascension	13 h
Declination	−50°
Area	1060 sq. deg. Ranked 9th
Number of stars (Bayer-Flamsteed)	65
Number of bright stars (magnitude < 3)	9
Number of nearby stars (Distance < 100 ly)	4
Brightest star	Alpha Centauri (α Cen) (App. magnitude −0.01)
Nearest Star	Alpha Centauri (α Cen) (Distance: 4.36 ly)
Meteor showers	Alpha Centaurids Omicron Centaurids Theta Centaurids
Bordering constellations	Antlia Carina Circinus Crux Hydra Libra (corner) Lupus Musca Vela
Visible at latitudes between +30° and −90° Best visible at 21:00 (9 p.m.) during the month of May

Centaurus (IPA: /ˌsɛnˈtɔːrəs/, Latin: centaur) is a bright constellation of the southern hemisphere. One of the largest constellations in the sky, Centaurus was one of the 48 constellations listed by Ptolemy, and also counts among the 88 modern constellations.

1 Notable features
2 Notable deep sky objects
3 History
4 Mythology
5 Notable and named stars
6 See also
7 External links

[edit] Notable features

Centaurus contains Proxima Centauri, a red dwarf that is the nearest known star (other than the Sun) to Earth as well as Alpha Centauri, which is a binary star to which Proxima Centauri is apparently gravitationally bound to form a triple star system.

In addition to Alpha Centauri, the fourth brightest star in the heavens, a second first magnitude star, Beta Centauri, is part of Centaurus. The constellation also contains BPM 37093, which is estimated to be a degenerate star, consisting of crystalline carbon.

[edit] Notable deep sky objects

It also contains Omega Centauri, the brightest globular cluster in the sky and Centaurus A, an elliptical galaxy.

[edit] History

It was mentioned by Eudoxus (4th century B.C.) and Aratus (3rd century B.C.), Ptolemy catalogued thirty-seven stars in it.

[edit] Mythology

The constellation, when including fainter stars visible to the naked eye, resembles a stick man with the back end of a horse attached [1]. According to Greek mythology, the constellation is Chiron who was a wise centaur (half-man, half-horse) known as a tutor to Jason (the leader of the Argonauts), and tutor to Herakles (a demi-god).

Centaurus is sometimes associated with the constellation Sagitta, an arrow which Centaurus appears to have fired towards the constellation Aquila. As such, together with the constellation Lupus, and the fact that Centaurus is below the ecliptic, this may have formed the basis of the myth of the Erymanthian Boar, one of The Twelve Labours of Herakles.

When the sun is in the sign of Virgo, it sits directly above the constellation Centaurus. The Greeks considered that the centaur Chiron, who was accidentally poisoned and died due to Herakles, while Herakles took a detour from hunting the Erymanthian Boar, was put in the sky as a mark of pity.

The constellation Lupus is next after Centaurus in the sun's transit, and was to the Greeks an arbitrary hunted animal (Therion)- it became a wolf under the Romans. Centaurus appears to have fired an arrow, the constellation Sagitta, towards Aquila, the eagle that tortured Prometheus, thus appearing to release Prometheus from his torment. Centaurus is also under the ecliptic, and thus considered to be in the underworld.

[edit] Notable and named stars

BD	F	Names and other designations	Mag.	Ly away	Comments
α		Alpha Centauri, Rigel Kentaurus, Toliman, Bungula	−0.01	4.36	triple star system, components: Alpha Centauri A -0.01 Alpha Centauri B 1.35 Proxima Centauri (α Cen C) 11.05 – closest star; flare star closest star system < رِجل القنطورس Al-Rigil al-Kentaurus The Foot of the Centaur < Toliman is either a variant of the Arabic الثالمين Al-Thalimain meaning "Ostriches", or it is Hebrew for "the Heretofore and the Hereafter" < Bungula is a combination of "B" for Beta Cen (error) + the Latin ungula for "hoof"
β		Beta Centauri, Hadar, Agena	0.61	525	< ? Hadar settled land, ground? < Agena is a combination of "A" for Alpha Cen (error) + the Latin genu for "knee" Beta Cephei variable
θ		Theta Centauri, Menkent	2.06	60.94	< منكب القنطورس Mankib al-Kentaurus ("Mankib" fused with "Kentaurus" to form men-kent) The Shoulder of the Centaur
γ		Gamma Centauri, Muhlifain, Miliphein	2.20	130.4	< محلفين muħlifayn (The star) sworn by [by two?] binary star, component magnitudes +2.9, +2.9
ε		Epsilon Centauri, Birdun, Al Birdhaun	2.29	376	< البرﺬﻮﻦ al-birdhaun the Packhorse Beta Cephei variable
η		Eta Centauri, Marfikent	2.33	309	< مرفق القنطورس Mirfaq al-Kentaurus ("Marfik" fused with "Kentaurus" to form marfi-kent) The Elbow of the Centaur Gamma Cassiopeiae variable
ζ		Zeta Centauri, Alnair, Al Nair al Baten	2.55	385	< البطن الناير Al-Na'ir al-baţn[u] The Bright One of the Stomach [of the Centaur] spectroscopic binary
δ		Delta Centauri, Ma Wei	2.58	395	< 马尾 ma wei "the Horse's Tail" Gamma Cassiopeiae variable
ι		Iota Centauri, Alhakim	2.75	58.62	< الحكيم Al-Hakeem from قنطورس الحكيم Kentaurus al-Hakeem, the Wise Centaur
λ		Lambda Centauri, Mati, Ma Ti	3.11	410	< 马蹄 ma ti "the Horse's Hoof"
κ		Kappa Centauri, Ke Kwan	3.13	539	< 騎官 (Mandarin qíguān) The cavalry officer
ν		Nu Centauri, Kabkent Secunda	3.41	475	< قلب القنطورس Qalb al-Kentaurus ( Arabic "Qalb" fused with "Kentaurus" to form kab-kent) The Heart of the Centaur + Latin "Secunda" for second rotating ellipsoidal variable Beta Cephei variable
μ		Mu Centauri, Kabkent Prima	3.47	527	< قلب القنطورس Qalb al-Kentaurus ( Arabic "Qalb" fused with "Kentaurus" to form kab-kent) The Heart of the Centaur + Latin "Prima" for first Gamma Cassiopeiae variable
φ		Phi Centauri, Kabkent Tertia	3.83	465	< قلب القنطورس Qalb al-Kentaurus ( Arabic "Qalb" fused with "Kentaurus" to form kab-kent) The Heart of the Centaur + Latin "Tertia" for third
τ		Tau Centauri	3.85	131.7
υ¹		Upsilon1 Centauri	3.87	418
π		Pi Centauri	3.90	321	binary star, component magnitudes: +4.3, +5.0
d		HD 117440, d Centauri	3.90	1250	binary star, component magnitudes: +4.5, +4.7
σ		Sigma Centauri	3.91	443
ρ		Rho Centauri	3.97	342
b		HD 129116, b Centauri	4.01	305
ψ		Psi Centauri	4.05	247
c¹		HD 129456, c¹ Centauri	4.06	205.3
g	2	2 Centauri, V806 Centauri	4.19	177.4	semiregular variable
i	1	1 Centauri	4.23	62.83
n		HD 111968, n Centauri	4.25	155.1
ξ²		Xi2 Centauri	4.27	412
j		HD 102776, j Centauri	4.30	459	Gamma Cassiopeiae variable
v		v Centauri	4.30	1190
k	3	3 Centauri, V983 Centauri	4.32	298	double star, component magnitudes 4.56, 6.06 possible eclipsing binary
e		HD 111915, e Centauri	4.33	303
υ²		Upsilon2 Centauri	4.34	448
χ		Chi Centauri	4.36	446	Beta Cephei variable
a		V761 Centauri, a Centauri	4.41	419	SX Arietis variable
B		B Centauri	4.47	464
m		HD 116243, m Centauri	4.52	257
J		J Centauri, V790 Centauri	4.52	355	Beta Cephei variable
A		A Centauri	4.62	463
l		l Centauri	4.63	355
M		M Centauri	4.64	257
w		w Centauri	4.66	188.4
f		HD 113703, f Centauri	4.71	414
h	4	4 Centauri	4.75	670
G		G Centauri	4.82	400
ξ¹		Xi1 Centauri	4.83	217.9
p		p Centauri	4.90	389
c²		HD 129685, c² Centauri	4.92	207.0
Q		Q Centauri	4.99	271	binary star, component magnitudes +5.7, +7.1
F		F Centauri	5.01	381
K		K Centauri	5.04	504
ο¹		Omicron1 Centauri	5.07	3200	semiregular variable
r		HD 115310, r Centauri	5.10	247
ο²		Omicron2 Centauri	5.12	3400	Alpha Cygni variable
z		z Centauri	5.15	429
H		H Centauri, V945 Centauri	5.17
C²		C2 Centauri	5.26	189.2
N		N Centauri	5.26	363
D		D Centauri	5.31	566	binary star, component magnitudes: +5.6, +6.8
x¹		x1 Centauri	5.32
E		E Centauri	5.34	590
u		u Centauri	5.45
C³		C3 Centauri	5.46	363
y		y Centauri	5.53
C¹		C1 Centauri, V763 Centauri	5.64	652	semiregular variable
x²		x2 Centauri	5.71
		HD 117618	7.18		has a planet
		R Centauri	7.18	2100	Mira variable H₂O maser
		HD 102117	7.47		has a planet
		BPM 37093	13.96		white dwarf variable
ω		Omega Centauri			globular cluster