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8 Leonis Minoris

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8 Leonis Minoris
Location of 8 Leonis Minoris (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Leo Minor
Right ascension 09h 31m 32.41045s[1]
Declination +35° 06′ 11.7793″[1]
Apparent magnitude (V) 5.37[2]
Characteristics
Evolutionary stage AGB[3]
Spectral type M1 IIIab[4]
U−B color index +1.81[2]
B−V color index +1.53[2]
Variable type suspected[5]
Astrometry
Radial velocity (Rv)39.83±0.18[6] km/s
Proper motion (μ) RA: −54.488 mas/yr[1]
Dec.: −97.434 mas/yr[1]
Parallax (π)6.6271 ± 0.0238 mas[1]
Distance492 ± 2 ly
(150.9 ± 0.5 pc)
Absolute magnitude (MV)−0.43[7]
Details
Mass1.59[8] M
Radius48.5[9] R
Luminosity417±17[10] L
Surface gravity (log g)1.153[11] cgs
Temperature3,978±122[12] K
Metallicity [Fe/H]−0.25[1] dex
Other designations
8 Leonis Minoris, AG+35°938, BD+35°2015, GC 13133, HD 82198, HIP 46735, HR 3769, SAO 61450[13]
Database references
SIMBADdata

8 Leonis Minoris (8 LMi) is a solitary,[14] red hued star located in the northern constellation Leo Minor. It has an apparent magnitude 5.37,[2] making it faintly visible to the naked eye. Based on parallax measurements from the Gaia satellite, the object is estimated to be 492 light years distant.[1] It is receding with a heliocentric radial velocity of 40 km/s.[6] At its current distance, 8 LMi is diminshed by 0.12 magnitudes due to interstellar dust.[15]

This is an asymptotic giant branch star[3] with stellar classification of M1 IIIab.[4] It has 1.59 times the mass of the Sun[8] but has expanded to 48.5 times its girth.[9] It radiates 417 times the luminosity of the Sun[10] from its enlarged photosphere at an effective temperature of 3,978 K.[12] 8 LMi has an iron abundance only half of the Sun's, making it metal deficient.[1]

8 LMi's variability was first observed to be variable in 1930 by Joel Stebbins.[16] However, Eggen (1967) instead lists it as an ordinary M-type giant and used the object for comparison.[17] In 1978-9, 8 LMi was again listed as a variable star but did not provide further insight.[18] As of 2017, the star has not been confirmed to be variable.[5]

References

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  1. ^ a b c d e f g 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 d Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". VizieR Online Data Catalog. 2237. Bibcode:2002yCat.2237....0D.
  3. ^ a b Eggen, Olin J. (July 1992). "Asymptotic giant branch stars near the sun". The Astronomical Journal. 104: 275. Bibcode:1992AJ....104..275E. doi:10.1086/116239. ISSN 0004-6256.
  4. ^ a b Yamashita, Y. (1967). "MK Spectral Types of Bright M-Type Stars". Publications of the Dominion Astrophysical Observatory Victoria. 13: 44. Bibcode:1967PDAO...13...47Y. ISSN 0078-6950.
  5. ^ a b Samus’, N. N.; Kazarovets, E. V.; Durlevich, O. V.; Kireeva, N. N.; Pastukhova, E. N. (January 2017). "General catalogue of variable stars: Version GCVS 5.1". Astronomy Reports. 61 (1): 80–88. Bibcode:2017ARep...61...80S. doi:10.1134/S1063772917010085. eISSN 1562-6881. ISSN 1063-7729. S2CID 125853869.
  6. ^ a b Famaey, B.; Pourbaix, D.; Frankowski, A.; Van Eck, S.; Mayor, M.; Udry, S.; Jorissen, A. (18 February 2009). "Spectroscopic binaries among Hipparcos M giants". Astronomy & Astrophysics. 498 (2): 627–640. arXiv:0901.0934. Bibcode:2009A&A...498..627F. doi:10.1051/0004-6361/200810698. eISSN 1432-0746. ISSN 0004-6361.
  7. ^ 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. eISSN 1562-6873. ISSN 1063-7737. S2CID 119257644.
  8. ^ a b Kervella, Pierre; Arenou, Frédéric; Mignard, François; Thévenin, Frédéric (March 2019). "Stellar and substellar companions of nearby stars from Gaia DR2". Astronomy & Astrophysics. 623 (4): A72. arXiv:1901.09170. Bibcode:2019MNRAS.484.4619G. doi:10.1051/0004-6361/201834371. eISSN 1432-0746. ISSN 0004-6361.
  9. ^ a b Kervella, Pierre; Arenou, Frédéric; Thévenin, Frédéric (20 December 2021). "Stellar and substellar companions from Gaia EDR3". Astronomy & Astrophysics. 657: A7. arXiv:2109.10912. Bibcode:2022A&A...657A...7K. doi:10.1051/0004-6361/202142146. eISSN 1432-0746. ISSN 0004-6361.
  10. ^ a b 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.
  11. ^ Ghosh, Supriyo; Mondal, Soumen; Das, Ramkrishna; Khata, Dhrimadri (29 January 2019). "Spectral Calibration of K−M Giants from medium resolution near-infrared HK-band spectra". Monthly Notices of the Royal Astronomical Society. 484 (4): 4619. arXiv:1901.09170. Bibcode:2019MNRAS.484.4619G. doi:10.1093/mnras/stz299. eISSN 1365-2966. ISSN 0035-8711.
  12. ^ a b 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. eISSN 1538-3881. hdl:1721.1/124721. S2CID 166227927.
  13. ^ "8 Leonis Minoris". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved November 13, 2022.
  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.
  15. ^ Gontcharov, George A.; Mosenkov, Aleksandr V. (28 September 2017). "Verifying reddening and extinction for Gaia DR1 TGAS main sequence stars". Monthly Notices of the Royal Astronomical Society. 472 (4): 3805–3820. arXiv:1709.01160. Bibcode:2017MNRAS.472.3805G. doi:10.1093/mnras/stx2219. eISSN 1365-2966. ISSN 0035-8711.
  16. ^ Stebbins, Joel; Huffer, Charles Morse (1930). "The constancy of the light of red stars". Publications of the Washburn Observatory. 15: 140–174. Bibcode:1930PWasO..15..140S.
  17. ^ Eggen, Olin J. (September 1967). "- and Broad-Band Photometry of Red Stars. Northern Giants". The Astrophysical Journal Supplement Series. 14: 307. Bibcode:1967ApJS...14..307E. doi:10.1086/190158. eISSN 1538-4365. ISSN 0067-0049.
  18. ^ Pyl'skaja, O. P.; Zakharova, P. E.; Polushina, T. S. (December 1978). "V-R Colours of Red Variable Stars". Information Bulletin on Variable Stars. 1513: 1. Bibcode:1978IBVS.1513....1P. ISSN 0374-0676.