| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Lyra |
| Right ascension | 19h 07m 18.13251s [2] |
| Declination | +36° 06′ 00.5592″ [2] |
| Apparent magnitude (V) | 5.22 [3] |
| Characteristics | |
| Spectral type | B6IV [4] |
| Variable type | Be star [5] |
| Astrometry | |
| Radial velocity (Rv) | −26.0±4.6 [6] km/s |
| Proper motion (μ) |
RA: −1.437
[2]
mas/
yr Dec.: −3.876 [2] mas/ yr |
| Parallax (π) | 3.5858 ± 0.1924 mas [2] |
| Distance | 910 ± 50
ly (280 ± 10 pc) |
| Absolute magnitude (MV) | −1.94 [7] |
| Orbit [8] | |
| Period (P) | 216.93 yr |
| Semi-major axis (a) | 0.172″ |
| Eccentricity (e) | 0.637 |
| Inclination (i) | 145.5° |
| Longitude of the node (Ω) | 171.4° |
| Periastron epoch (T) | B 1997.28 |
|
Argument of periastron (ω) (secondary) | 201.2° |
| Details | |
| Mass | 5.2 [9] M☉ |
| Radius | 6.7 [10] R☉ |
| Luminosity | 854 [10] L☉ |
| Surface gravity (log g) | 3.54 [9] cgs |
| Temperature | 12,059 [10] K |
| Metallicity [Fe/H] | −0.11 [9] dex |
| Rotational velocity (v sin i) | 224 [11] km/s |
| Age | 168 [12] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
ι Lyrae, Latinised as Iota Lyrae, is a binary star [3] in the northern constellation of Lyra. It is visible to the naked eye as a dim, blue-white hued star with an apparent visual magnitude that fluctuates around 5.22. [3] This object is located approximately 910 light years distant from the Sun based on parallax, but is drifting nearer with a radial velocity of −26 km/s. [6]
This is a wide binary system with a computed orbital period of 217 years and an eccentricity of 0.6. [8] The primary component has a stellar classification of B6IV, [4] matching a B-type subgiant star. It is a Be star, [14] displaying emission lines in its spectrum, and is spinning rapidly with a projected rotational velocity of 224 km/s. [11] The star ranges in brightness from magnitude 5.20 down to 5.27. [5] It has about five times the mass of the Sun and is radiating 854 times the Sun's luminosity from its photosphere at an effective temperature of 12,059 K.
References
- ^ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 3 January 2023.
- ^ a b c d e 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.
- ^ a b c 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.
- ^ a b 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.
- ^ a b 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.
- ^ a b Gontcharov, G. A. (November 2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv: 1606.08053. Bibcode: 2006AstL...32..759G. doi: 10.1134/S1063773706110065. S2CID 119231169.
- ^ Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv: 1108.4971. Bibcode: 2012AstL...38..331A. doi: 10.1134/S1063773712050015. S2CID 119257644.
- ^ a b "Sixth Catalog of Orbits of Visual Binary Stars". United States Naval Observatory. Archived from the original on 1 August 2017. Retrieved 15 March 2017.
- ^ a b c Anders, F.; et al. (August 2019). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18". Astronomy & Astrophysics. 628: A94. arXiv: 1904.11302. Bibcode: 2019A&A...628A..94A. doi: 10.1051/0004-6361/201935765. eISSN 1432-0746. ISSN 0004-6361.
- ^ a b c McDonald, I.; Zijlstra, A. A.; Watson, R. A. (15 June 2017). "Fundamental parameters and infrared excesses of Tycho–Gaia stars". Monthly Notices of the Royal Astronomical Society. 471 (1): 770–791. arXiv: 1706.02208. Bibcode: 2017MNRAS.471..770M. doi: 10.1093/mnras/stx1433. eISSN 1365-2966. ISSN 0035-8711.
- ^ a b Zorec, J.; Royer, F. (2012). "Rotational velocities of A-type stars. IV. Evolution of rotational velocities". Astronomy & Astrophysics. 537: A120. arXiv: 1201.2052. Bibcode: 2012A&A...537A.120Z. doi: 10.1051/0004-6361/201117691. S2CID 55586789.
- ^ Gontcharov, G. A. (December 2012). "Dependence of kinematics on the age of stars in the solar neighborhood". Astronomy Letters. 38 (12): 771–782. arXiv: 1606.08814. Bibcode: 2012AstL...38..771G. doi: 10.1134/S1063773712120031. ISSN 0320-0108. S2CID 255201789.
- ^ "iot Lyr". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-09-04.
- ^ Abt, H. A.; Cardona, O. (October 1984), "Be stars in binaries", Astrophysical Journal, 285: 190–194, Bibcode: 1984ApJ...285..190A, doi: 10.1086/162490