Astronomy:Lambda Mensae
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Mensa |
| Right ascension | 05h 47m 48.13340s[1] |
| Declination | −72° 42′ 08.0993″[1] |
| Apparent magnitude (V) | 6.53[2] |
| Characteristics | |
| Spectral type | K0 III[3] |
| Apparent magnitude (B) | 7.614[4] |
| Apparent magnitude (J) | 4.820[5] |
| Apparent magnitude (H) | 4.163[5] |
| Apparent magnitude (K) | 4.119[5] |
| U−B color index | +0.97[2] |
| B−V color index | +1.08[2] |
| Astrometry | |
| Radial velocity (Rv) | 15.35±0.13[6] km/s |
| Proper motion (μ) | RA: -7.013[6] mas/yr Dec.: +24.451[6] mas/yr |
| Parallax (π) | 6.9890 ± 0.0139[6] mas |
| Distance | 466.7 ± 0.9 ly (143.1 ± 0.3 pc) |
| Absolute magnitude (MV) | +0.84[7] |
| Details | |
| Radius | 10[8] R☉ |
| Luminosity | 54[9] L☉ |
| Surface gravity (log g) | 2.43[10] cgs |
| Temperature | 4,713[10] K |
| Other designations | |
| Database references | |
| SIMBAD | data |
Lambda Mensae, Latinized from λ Mensae, is an orange-hued star in the southern constellation of Mensa. It has an apparent visual magnitude of 6.53,[2] which places it at or near the limit on stars visible to the naked eye. According to the Bortle scale, it requires a dark night from rural skies for this star to be viewed. Though it has the designation Lambda, it is actually the twenty-fourth-brightest star in the constellation and not the eleventh-brightest.
This is an evolved K-type giant star with a stellar classification of K0 III.[3] It is a red clump star, which means it is generating energy through helium fusion at its core.[5] The measured angular diameter is 0.68±0.01 mas.[12] At an estimated distance of the star, this yields a physical size of about 10 times the radius of the Sun.[8] It is radiating 54[9] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,713 K.[10]
References
- ↑ 1.0 1.1 van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, doi:10.1051/0004-6361:20078357, Bibcode: 2007A&A...474..653V.
- ↑ 2.0 2.1 2.2 2.3 Johnson, H. L. et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory 4 (99): 99, Bibcode: 1966CoLPL...4...99J.
- ↑ 3.0 3.1 Houk, Nancy; Cowley, A. P. (1979), Michigan catalogue of two-dimensional spectral types for the HD stars, 1, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode: 1978mcts.book.....H.
- ↑ Høg, E. et al. (2000), "The Tycho-2 catalogue of the 2.5 million brightest stars", Astronomy and Astrophysics 355: L27, doi:10.1888/0333750888/2862, Bibcode: 2000A&A...355L..27H.
- ↑ 5.0 5.1 5.2 5.3 Laney, C. D. et al. (January 2012), "A new Large Magellanic Cloud K-band distance from precision measurements of nearby red clump stars", Monthly Notices of the Royal Astronomical Society 419 (2): 1637–1641, doi:10.1111/j.1365-2966.2011.19826.x, Bibcode: 2012MNRAS.419.1637L.
- ↑ 6.0 6.1 6.2 6.3 Brown, A. G. A. (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics 649: A1. doi:10.1051/0004-6361/202039657. Bibcode: 2021A&A...649A...1G. Gaia EDR3 record for this source at VizieR.
- ↑ Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode: 2012AstL...38..331A.
- ↑ 8.0 8.1 Lang, Kenneth R. (2006), Astrophysical formulae, Astronomy and astrophysics library, 1 (3rd ed.), Birkhäuser, ISBN 3-540-29692-1, https://books.google.com/books?id=OvTjLcQ4MCQC&pg=PA41. The radius (R*) is given by:
- [math]\displaystyle{ \begin{align} 2\cdot R_* & = \frac{(138.7\cdot 0.68\cdot 10^{-3})\ \text{AU}}{0.0046491\ \text{AU}/R_{\bigodot}} \\ & \approx 20\cdot R_{\bigodot} \end{align} }[/math]
- ↑ 9.0 9.1 McDonald, I. et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society 427 (1): 343–57, doi:10.1111/j.1365-2966.2012.21873.x, Bibcode: 2012MNRAS.427..343M.
- ↑ 10.0 10.1 10.2 Kordopatis, G. et al. (November 2013), "The Radial Velocity Experiment (RAVE): Fourth Data Release", The Astronomical Journal 146 (5): 36, doi:10.1088/0004-6256/146/5/134, 134, Bibcode: 2013AJ....146..134K.
- ↑ "lam Men". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=lam+Men.
- ↑ Richichi, A. et al. (February 2005), "CHARM2: An updated Catalog of High Angular Resolution Measurements", Astronomy and Astrophysics 431 (2): 773–777, doi:10.1051/0004-6361:20042039, Bibcode: 2005A&A...431..773R.
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