A light curve for Delta Librae, adapted from Shobbrook (2005)[1]
Observation data Epoch J2000 Equinox J2000
Constellation
Libra
Right ascension
15h 00m 58.34830s[2]
Declination
−08° 31′ 08.2104″[2]
Apparent magnitude (V)
4.93[3]
Characteristics
Spectral type
B9.5V[4]
U−B color index
–0.10[5]
B−V color index
+0.00[5]
Variable type
Eclipsing binary of Algol type (EA/SD)[6]
Astrometry
Radial velocity (Rv)
−38.7±2[7] km/s
Proper motion (μ)
RA: −63.051[2] mas/yr Dec.: −6.024[2] mas/yr
Parallax (π)
9.2824 ± 0.4725 mas[2]
Distance
350 ± 20 ly (108 ± 5 pc)
Absolute magnitude (MV)
+0.15[8]
Orbit[9]
Period (P)
2.3274 d
Eccentricity (e)
0.07
Semi-amplitude (K1) (primary)
76.6 km/s
Semi-amplitude (K2) (secondary)
218.7 km/s
Details
δ Lib A
Mass
4.9±0.2[9]M☉
Radius
3.94[10]R☉
Luminosity
86[8]L☉
Temperature
8800[10] K
Age
0.5[10] Gyr
δ Lib B
Mass
1.7±0.2[9]M☉
Other designations
δ Lib, Zuben Elakribi, 19 Librae, BD–07°3938, HD 132742, HIP 73473, HR 5586, SAO 140270
Database references
SIMBAD
data
Delta Librae, Latinized from δ Librae, is a variable star in the constellation Libra. It has the traditional name Zuben Elakribi, a variant of the traditional name of Gamma Librae.[11] With μ Virginis it forms one of the Akkadian lunar mansions Mulu-izi[12](meaning "Man-of-fire"[13]).
δ Librae is approximately 300 light years from the Earth and the primary, component A, belongs to the spectral class B9.5V, indicating it is a B-type main-sequence star. It is visible to the naked eye with an apparent visual magnitude of 4.93[3] and is moving closer to the Sun with a radial velocity of −39 km/s.[7] This is an Algol-like eclipsing binary star system, with a period of 2.3274 days and an eccentricity of 0.07.[9] Its apparent magnitude varies from 4.91m to 5.9m.[14] The secondary is filling its Roche lobe and there is evidence of large-scale mass transfer in the past, with the star being more evolved than the primary.[9]
Along with λ Tauri, it was one of the first stars on which
rotational line broadening[15] was observed, by Frank Schlesinger in 1911.
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DeltaLibrae, Latinized from δ Librae, is a variable star in the constellation Libra. It has the traditional name Zuben Elakribi, a variant of the traditional...
Gliese 570 (or 33 G. Librae) is a quaternary star system approximately 19 light-years away. The primary star is an orange dwarf star (much dimmer and smaller...
Geminorum 20.1° East 25 October 1947 01:45 Venus Zuben-el-genubi (Alpha-2 Librae) 13.5° East 7 July 1959 14:30 Venus Regulus 44.5° East 27 September 1965...
K. A. Jr. (April 1976), "Radial-velocity variations of SZ Lyncis and EH Librae", Publications of the Astronomical Society of the Pacific, 88: 164–167,...
2.75 Delta Ophiuchi Star Suspected variable star 2.74 Gamma Virginis Binary star system 2.74 Eta Draconis Binary star system 2.75 Alpha2 Librae Binary...
remains uncertain. This group contains about 16 stars, including Alpha Librae, Alpha Cephei, Castor, Fomalhaut and Vega. All members of the group are...
reassigned from Scorpius to Libra and given the new names Sigma and Upsilon Librae.: p. 196 (To add to the confusion, the star now known as Omicron Scorpii...
Cepheids and cepheid-like Type I (Classical cepheids, Delta Scuti) Type II (BL Herculis, W Virginis, RV Tauri) RR Lyrae Rapidly oscillating Ap SX Phoenicis...
strong chromospheric emission lines. Examples are FK Com, V1794 Cygni and UZ Librae. A possible explanation for the rapid rotation of FK Comae stars is that...
orbit and mean apparent path of the Sun) the next brightest of which is δ (Delta) Geminorum, of magnitude +3.53. As Regulus closely aligns to the mean orbits...
and Pegasus Bufo /ˈbjuːfoʊ/ Bufonis Toad 1754 John Hill 58 Hydrae, Sigma Librae tail of Hydra Cancer Minor /ˈkænsərˈmaɪnər/ Cancri Minoris Lesser Crab 1613...
Retinue 92 Leonis 虎賁 Hǔ Bēn Emperor's Bodyguard 72 Leonis 日 Rì Sun Kappa Librae Libra A single-star asterism in the Room mansion 騎陣將軍 Qí Zhèn Jiāng Jūn...
boundary between stellar kinematic groups and very wide binaries . II. α Librae + KU Librae: a common proper motion system in Castor separated by 1.0 pc". Astronomy...