HR 4177, also called t² Carinae (t²Car), is a double star^[2] in the southern constellationofCarina. It is faintly visible to the naked eye with a combined apparent visual magnitude of +4.77.^[2] The two components are HD 92397 and HD 92398. The primary component is located at a distance of approximately 1,600 light years from the Sun based on parallax, and is drifting further away with a radial velocity of +11 km/s.^[3] It has a peculiar velocityof24.3+9.9
−16.1 km/s and may be a runaway star.^[4] The star is a member of the BH 99 cluster.^[7]

The magnitude 4.85^[2] primary, component A, is a massive K-type supergiantorbright giant with a stellar classification of K4.5Ib-II.^[3] Houk (1978) instead listed it with a class of K4/5III: but with some uncertainty about the classification.^[8] It has 12^[4] times the mass of the Sun and has expanded to 202^[1] times the Sun's radius. The star is radiating 8,478^[1] times the luminosity of the Sun from its bloated photosphere at an effective temperature of 3,900 K.^[1]

The magnitude 7.48 companion star, component B, was discovered by J. Dunlop in 1829. As of 2015, it was located at an angular separationof14.60″ along a position angle of 21°, relative to the primary.^[9] It is a B-type giant/bright giant star with a class of B9II/III.^[3] The pair show a common proper motion and roughly similar parallax measurements,^[1] but it remains unclear whether they form a gravitationally-bound pair.^[2]

References[edit]

^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p
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.
- A: 5350588691654540544

B: 5350588691654545792

^ ^a ^b ^c ^d ^e Eggleton, P. P.; Tokovinin, A. A. (2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.

^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ 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 ^c ^d Tetzlaff, N.; et al. (January 2011), "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun", Monthly Notices of the Royal Astronomical Society, 410 (1): 190–200, arXiv:1007.4883, Bibcode:2011MNRAS.410..190T, doi:10.1111/j.1365-2966.2010.17434.x, S2CID 118629873.

^ ^a ^b "HD 92397". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-07-13.

^ "HD 92398". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-07-13.

^ Cantat-Gaudin, T.; et al. (October 2018), "A Gaia DR2 view of the open cluster population in the Milky Way", Astronomy & Astrophysics, 618: 16, arXiv:1805.08726, Bibcode:2018A&A...618A..93C, doi:10.1051/0004-6361/201833476, S2CID 56245426, A93.

^ Houk, Nancy (1978), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 1, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode:1975mcts.book.....H.

^ Mason, B. D.; et al. (2014), The Washington Visual Double Star Catalog, Bibcode:2001AJ....122.3466M, doi:10.1086/323920, retrieved 2015-07-22