Epsilon Mensae, Latinized to ε Mensae, is a single[14] star in the southern circumpolar constellation Mensa. It has an apparent magnitude of 5.52,[2] making it faintly visible to the naked eye under ideal conditions. The object has a heliocentric radial velocity of 10.5 km/s,[5] meaning it is receding from the Solar System, and is estimated to be 454 light years away.[1]

ε Mensae
Location of ε Mensae (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Mensa
Right ascension 07h 25m 38.0987s[1]
Declination −79° 05′ 39.0878″[1]
Apparent magnitude (V) 5.52±0.01[2]
Characteristics
Spectral type K2/3 III[3]
U−B color index +1.42[4]
B−V color index +1.28[4]
Astrometry
Radial velocity (Rv)10.5±2.9[5] km/s
Proper motion (μ) RA: −29.197 mas/yr[1]
Dec.: +5.181 mas/yr[1]
Parallax (π)7.1874 ± 0.0449 mas[1]
Distance454 ± 3 ly
(139.1 ± 0.9 pc)
Absolute magnitude (MV)−0.24[6]
Details
Mass1.15[7] M
Radius21.94[8] R
Luminosity170[9] L
Surface gravity (log g)1.74[7] cgs
Temperature4,657±122[8] K
Metallicity [Fe/H]−0.31[10] dex
Rotational velocity (v sin i)1.8±1.4[11] km/s
Age233[1] Myr
Other designations
ε Men, 43 G. Mensae, CPD−78°265, FK5 2583, GC 10055, HD 60816, HIP 36039, HR 2919, SAO 256415[12][13]
Database references
SIMBADdata

Epsilon Mensae has a stellar classification of K2/3 III — intermediate between a K2 and K3 giant star.[3] It has 115% the mass of the Sun[7] and an enlarged radius of 21.9 R. It shines at 170 times the luminosity of the Sun[9] from its photosphere at an effective temperature of 4,657 K,[8] giving it an orange glow. Epsilon Mensae has a metallicity 49% that of the Sun and is believed to be a member of the young disk population.[10] It spins leisurely with a projected rotational velocity of about 1.8 km/s.[11]

References

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  1. ^ a b c d e f Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  2. ^ a b Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (March 2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27–L30. Bibcode:2000A&A...355L..27H. ISSN 0004-6361.
  3. ^ a b Houk, N.; Cowley, A. P. (1975). University of Michigan Catalogue of two-dimensional spectral types for the HD stars. Volume I. Declinations -90_ to -53_ƒ0. Bibcode:1975mcts.book.....H.
  4. ^ a b Johnson, H. L.; Mitchell, R. I.; Iriarte, B.; Wisniewski, W. Z. (1966). "UBVRIJKL Photometry of the Bright Stars". Communications of the Lunar and Planetary Laboratory. 4: 99–110. Bibcode:1966CoLPL...4...99J.
  5. ^ 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. ISSN 1063-7737. S2CID 119231169.
  6. ^ Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331–346. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. ISSN 1063-7737. S2CID 255204555.
  7. ^ 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. ISSN 0004-6361.
  8. ^ a b c Stassun, Keivan G.; et al. (9 September 2019). "The Revised TESS Input Catalog and Candidate Target List". The Astronomical Journal. 158 (4): 138. arXiv:1905.10694. Bibcode:2019AJ....158..138S. doi:10.3847/1538-3881/ab3467. ISSN 0004-6256.
  9. ^ a b 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.
  10. ^ a b Eggen, Olin J. (January 1989). "Large and Kinematically Unbiased Samples of G- and K-Type Stars. III. Evolved Young Disk Stars in the Bright Star Sample". Publications of the Astronomical Society of the Pacific. 101: 54. Bibcode:1989PASP..101...54E. doi:10.1086/132404. eISSN 1538-3873. ISSN 0004-6280.
  11. ^ a b De Medeiros, J. R.; Alves, S.; Udry, S.; Andersen, J.; Nordström, B.; Mayor, M. (January 2014). "A catalog of rotational and radial velocities for evolved stars: V. Southern stars⋆⋆⋆". Astronomy & Astrophysics. 561: A126. arXiv:1312.3474. Bibcode:2014A&A...561A.126D. doi:10.1051/0004-6361/201220762. ISSN 0004-6361.
  12. ^ "eps Men". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved June 14, 2022.
  13. ^ Gould, Benjamin Apthorp (1878). "Uranometria Argentina : brillantez y posicion de las estrellas fijas, hasta la septima magnitud, comprendidas dentro de cien grados del polo austral : con atlas". Resultados del Observatorio Nacional Argentino. 1. Bibcode:1879RNAO....1.....G.
  14. ^ Eggleton, P. P.; Tokovinin, A. A. (11 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. eISSN 1365-2966. ISSN 0035-8711.