16 Lacertae Triple star system in the constellation Lacerta
16 Lacertae
Observation dataEpoch J2000.0 Equinox J2000.0
Constellation Lacerta
Right ascension 22h 56m 23.62929s [ 2]
Declination +41° 36′ 13.9482″ [ 2]
Apparent magnitude (V)± 0.015[ 3]
Characteristics
Spectral type B2 IV[ 4] [ 5]
Variable type β Cep [ 6] Algol [ 7]
Astrometry Radial velocity (Rv )± 0.04[ 8] km/s Proper motion (μ) RA: −1.188[ 2] mas /yr Dec.: −4.290[ 2] mas /yr Parallax (π)2.0692± 0.0865 mas [ 2] Distance 1,580 ± 70 ly pc ) Absolute magnitude (MV )± 0.14[ 3] Orbit [ 9] Period (P)12.0969 d Eccentricity (e)± 0.0026Periastron epoch (T)± 2.1Semi-amplitude 1 )± 0.05 km/sDetails[ 3] 16 Lac A Mass ± 0.03 M ☉ Radius ± 0.4 R ☉ Luminosity +1,151 L ☉ Surface gravity (log g )± 0.05 cgs Temperature ± 200 K Metallicity [Fe/H] ± 0.08[ 10] dex Rotational velocity (v sin i )± 1[ 10] km/sOther designations 16 Lac , EN Lac , BD +40°4949HD 216916HIP 113281HR 8725SAO 52512[ 11] Database references SIMBAD data
16 Lacertae is a triple star [ 5] constellation of Lacerta , located about 1,580[ 2] light years from the Sun. It has the variable star designation EN Lacertae ; 16 Lacertae is the Flamsteed designation . This system is visible to the naked eye as a faint blue-white hued star with a maximum apparent visual magnitude of +5.587.[ 3] radial velocity of –12 km/s.[ 8]
The binary nature of the brighter component was discovered in 1910 by astronomer Oliver J. Lee at Yerkes Observatory . The first orbital elements were published by Otto Struve and Nicholay T. Bobrovnikov in 1925.[ 12] spectroscopic binary with an orbital period of 12.1 days and a small eccentricity of 0.05. It forms an eclipsing binary variable, although only the eclipse of the primary component has been detected. This component is a Beta Cephei variable star with three dominant pulsation modes having frequencies of around six per day.[ 6] stellar classification of B2 IV,[ 4] B-type subgiant star with 9.5 times the mass of the Sun and 5.6 times the Sun's radius .[ 3]
The unseen secondary is an F-type star of class F6–7. The tertiary component is a magnitude 11.4 star with a class of F0. As of 2008, it was located at an angular separation of ″ [ 5]
References
↑ "MAST: Barbara A. Mikulski Archive for Space Telescopes" . Space Telescope Science Institute. Retrieved 8 December 2021 .1 2 3 4 5 6 Brown, A. G. A. ; et al. (Gaia collaboration ) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties" . Astronomy & Astrophysics 616 . A1. arXiv :1804.09365 Bibcode :2018A& A...616A...1G doi :10.1051/0004-6361/201833051 Gaia DR2 record for this source at VizieR . 1 2 3 4 5 Nieva, María-Fernanda; Przybilla, Norbert (2014). "Fundamental properties of nearby single early B-type stars". Astronomy & Astrophysics . 566 : A7. arXiv :1412.1418 Bibcode :2014A& A...566A...7N . doi :10.1051/0004-6361/201423373 . S2CID 119227033 . 1 2 Lesh, Janet Rountree (December 1968). "The Kinematics of the Gould Belt: an Expanding Group?" . Astrophysical Journal Supplement . 17 : 371. Bibcode :1968ApJS...17..371L . doi :10.1086/190179 1 2 3 Eggleton, P. P.; Tokovinin, A. A. (September 2008). "A catalogue of multiplicity among bright stellar systems" . Monthly Notices of the Royal Astronomical Society 389 (2): 869– 879. arXiv :0806.2878 Bibcode :2008MNRAS.389..869E . doi :10.1111/j.1365-2966.2008.13596.x S2CID 14878976 . 1 2 Jerzykiewicz, M.; et al. (2015). "The 2003–2004 multisite photometric campaign for the β Cephei and eclipsing star 16 (EN) Lacertae with an appendix on 2 Andromedae, the variable comparison star" . Monthly Notices of the Royal Astronomical Society . 454 (1): 724– 740. arXiv :1508.05250 Bibcode :2015MNRAS.454..724J . doi :10.1093/mnras/stv1958 S2CID 119220117 . ↑ Samus, N. N.; et al. (2017). "General Catalogue of Variable Stars". Astronomy Reports . 5.1. 61 (1): 80– 88. Bibcode :2017ARep...61...80S . doi :10.1134/S1063772917010085 . S2CID 125853869 . 1 2 Pourbaix, D.; et al. (2004). "SB9: The Ninth Catalogue of Spectroscopic Binary Orbits". Astronomy & Astrophysics . 424 : 727– 732. arXiv :astro-ph/0406573 Bibcode :2004A& A...424..727P . doi :10.1051/0004-6361:20041213 . S2CID 119387088 . ↑ Lehmann, H.; et al. (February 2001). "A new analysis of the radial velocity variations of the eclipsing and spectroscopic binary EN Lacertae" . Astronomy and Astrophysics . 367 : 236– 249. Bibcode :2001A& A...367..236L . doi :10.1051/0004-6361:20000344 1 2 Nieva, M.-F.; Przybilla, N. (2012). "Present-day cosmic abundances. A comprehensive study of nearby early B-type stars and implications for stellar and Galactic evolution and interstellar dust models". Astronomy & Astrophysics . 539 : A143. arXiv :1203.5787 Bibcode :2012A& A...539A.143N . doi :10.1051/0004-6361/201118158 . S2CID 119206639 . ↑ "16 Lac" . SIMBAD Centre de données astronomiques de Strasbourg . Retrieved 2019-02-02 .↑ Struve, O.; Bobrovnikoff, N. T. (September 1925). "Orbit of the spectroscopic binary 16 Lacertae". Astrophysical Journal . 62 : 139– 143. Bibcode :1925ApJ....62..139S . doi :10.1086/142919 .
