Eta Centauri, a blue main-sequence star in Centaurus

Eta Centauri (HIP 71352)

Eta Centauri is a blue main-sequence star in the constellation Centaurus. At 305 light years away, it is the 80th brightest star in the Earth's sky, where it shines at an apparent visual magnitude of 2.33. It an intrinsic variable star that varies between magntitudes 2.25 and 2.32 over a period of 30.72 hours. It is moving through the Galaxy at a speed of 21.2 km/s relative to the Sun and is part of the Lower Centaurus Crux moving group. Its projected Galactic orbit carries it between 22,200 and 24,100 light years from the center of the Galaxy.

Sky position: RA 14h 35.5m, Dec -42° 9.6'

Common designations: Eta Centauri, HIP 71352, HD 127972, HR 5440

Learn how to find naked-eye stars with:

Stars of the Northern Hemisphere
Deluxe Astronomy Poster Brightest stars in Centaurus:
(list all)

1

| -0.01

) Alpha Centauri A

Rank	Mag.	Star
2	0.61	Hadar
3	1.35	Alpha Centauri B
4	2.06	Menkent
5	2.20	Gamma Centauri
6	2.29	Epsilon Centauri

7

| 2.33

) Eta Centauri

Rank	Mag.	Star
8	2.55	Zeta Centauri
9	2.58	Delta Centauri
10	2.75	Iota Centauri
11	3.11	Lambda Centauri
12	3.13	Kappa Centauri
13	3.41	Nu Centauri
14	3.47	Mu Centauri
15	3.83	Phi Centauri
16	3.85	Tau Centauri
17	3.87	Upsilon-1 Centauri

Location of Eta Centauri circled Map detail from Stars of the Northern Hemisphere
Hover over other bright stars to identify or click to jump.

Galactic Orbit of Eta Centauri
(compared to the Sun)

E

ccentricity: 4.1% vs. 16.0%

Angle φ : 147.0°vs. 26.0°

Semi-major axis : 7,087 pc vs. 8,686 pc

Semi-minor axis: 7,081 pc vs. 8,574 pc

Focus-to-center

: 292 pcvs. 1,388 pc

Semilatus rectum : 7,075 pc vs. 8,464 pc

Perigalacticon: 6,795 pc vs. 7,297 pc

Apogalacticon

: 7,379 pcvs. 10,074 pc
  Some Tabulated XHIP Data for Eta Centauri
(see also: SIMBAD)

Astrometry
2007A&A...474..653V

Position	Proper Motion
Right Ascension:	218.87688121° ±0.17 mas	-34.73 ±0.23 mas/yr.
Declination:	-42.15774569° ±0.11 mas	-32.72 ±0.18 mas/yr.
Galactic Longitude:	322.77411199°	-45.05 mas/yr.
Galactic Latitude:	16.66917603°	-15.73 mas/yr.

Parallax: 10.67 ± 0.21 mas

Spectrography

Spectral Type: B1.5 VN 1978MSS...C02....0H.

Radial Velocity: 0.00 ±1.60 km/s [A rating] 2006AstL...32..759G.

Iron Abundance [Fe/H]: n/a

Photometry
 

band	magnitude	Abs. Mag.
U	1.29	-3.57
B	2.17	-2.69
V	2.33	-2.53
R
I	2.48	-2.38
J	2.75	-2.11
H	2.78	-2.08
K	2.75	-2.11

B-V: -0.16 V-I: -0.15

Derivations

Heliocentric distance: 93.68 pc (fitted to cluster)

Galactocentric distance: 7,329 pc

Transverse velocity: 21.2 km/s

3D heliocentric position and motion:

toward:	Galactic center	Galactic rotation	North Galactic Pole
Position ( X, Y, Z)	71.5 pc	-54.3 pc	26.9 pc
Velocity (U, V, W)	-10.5 km/s	-17.1 km/s	-6.7 km/s