Iota Mensae

ι Mensae
Location of ι Mensae (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Mensa
Right ascension 05h 35m 36.1787s[1]
Declination −78° 49′ 15.129″[1]
Apparent magnitude (V) 6.00 - 6.05[2]
Characteristics
Spectral type B8 III[3]
B−V color index −0.022[4]
Variable type Ellipsoidal?[2]
Astrometry
Radial velocity (Rv)12.6±4.3[5] km/s
Proper motion (μ) RA: +5.547[1] mas/yr[1]
Dec.: +25.710[1] mas/yr[1]
Parallax (π)3.7076 ± 0.1819 mas[1]
Distance880 ± 40 ly
(270 ± 10 pc)
Absolute magnitude (MV)−1.03[6]
Details
Mass3.6[1] M
Radius9.5[1] R
Luminosity301[1] L
Surface gravity (log g)3.4[7] cgs
Temperature11,272±264[8] K
Metallicity [Fe/H]+0.13[9] dex
Age203[1] Myr
Other designations
ι Men, CD−78°216, HD 38602, HIP 26264, HR 1991, SAO 256214[10]
Database references
SIMBADdata

Iota Mensae is a single star about 880 light years away in the faint constellation Mensa. It has a very slightly variable apparent magnitude of 6.0, making it visible with the naked eye under good skies.

Iota Mensae has a spectral type of B8III, indicating that it has exhausted hydrogen at its core and expanded away from the main sequence. It is about 3.6 times the mass (M), 301 times as luminous, and has swollen to 9.5 times the radius of the Sun (R). It is calculated to be 314 million years old.

It has been catalogued as a chemically peculiar star with abnormally strong lines of silicon in its spectrum but this classification is now considered doubtful.[11] Its brightness varies by a few hundredths of a magnitude. Its period was initially measured at 2.6 days,[12] but this is now considered to be a period of 5.3 days with primary and secondary minima of a similar depth. The variability is thought to be due to the rotation of the star.[2]

References[edit]

  1. ^ a b c d e f g h i j 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 c Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1: B/gcvs. Bibcode:2009yCat....102025S.
  3. ^ Houk, Nancy (1975). "Michigan catalogue of two-dimensional spectral types for the HD stars". University of Michigan Catalogue of Two-Dimensional Spectral Types for the Hd Stars. Volume I. Declinations -90_ to -53_Ƒ0. 1. Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan. Bibcode:1975mcts.book.....H.
  4. ^ 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.
  5. ^ 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. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. S2CID 119257644.
  7. ^ Lafrasse, Sylvain; Mella, Guillaume; Bonneau, Daniel; Duvert, Gilles; Delfosse, Xavier; Chesneau, Olivier; Chelli, Alain (16 July 2010). "Building the 'JMMC Stellar Diameters Catalog' using SearchCal". Optical and Infrared Interferometry II. Vol. 7734. pp. 77344E. arXiv:1009.0137. Bibcode:2010SPIE.7734E..4EL. doi:10.1117/12.857024. S2CID 32097037.
  8. ^ 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. ^ Anders, F.; et al. (February 2022). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia EDR3 stars brighter than G = 18.5". Astronomy & Astrophysics. 658: A91. arXiv:2111.01860. Bibcode:2022A&A...658A..91A. doi:10.1051/0004-6361/202142369. eISSN 1432-0746. ISSN 0004-6361.
  10. ^ "Iota Men". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2021-02-18.
  11. ^ Renson, P.; Manfroid, J. (2009). "Catalogue of Ap, HGMN and Am stars". Astronomy and Astrophysics. 498 (3): 961. Bibcode:2009A&A...498..961R. doi:10.1051/0004-6361/200810788.
  12. ^ Grønbech, B.; Naqvi, S. I. H. (1976). "HR 1991. A new variable B star". Astronomy and Astrophysics Supplement Series. 26: 147. Bibcode:1976A&AS...26..147G.