9 Cassiopeiae

9 Cassiopeiae
Location of 9 Cassiopeiae (circled)
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Cassiopeia
Right ascension 00h 04m 13.6625s[1]
Declination +62° 17′ 15.591″[1]
Apparent magnitude (V) +5.884[2]
Characteristics
Spectral type A1II-III[3]
U−B color index +0.29[4]
B−V color index +0.30[4]
Astrometry
Radial velocity (Rv)−23.43±0.16[1] km/s
Proper motion (μ) RA: −0.936[1] mas/yr
Dec.: −0.263[1] mas/yr
Parallax (π)1.3781 ± 0.0237 mas[1]
Distance2,370 ± 40 ly
(730 ± 10 pc)
Details
Mass5.1[5] M☉
Radius26[6] R☉
Luminosity2,208[6] L☉
Surface gravity (log g)2.08[5] cgs
Temperature7,719[6] K
Metallicity [Fe/H]−0.32[5] dex
Rotational velocity (v sin i)33[7] km/s
Age25.1[8] Myr
Other designations
9 Cas, HR 9100, HD 225180, BD+61°2586, HIP 330
Database references
SIMBADdata

9 Cassiopeiae (9 Cas) is a white giant star in the constellation Cassiopeia, about 2,370 light years away.

9 Cassiopeiae is classified as an A1 type giant or bright giant. One study noted peculiarities in the spectrum that could indicate a λ Boötis star,[9] but other researchers have refuted this.[10][7]

At an age of 25 million years, 9 Cassiopeiae has expanded away from the main sequence after exhausting its core hydrogen and now has a radius about 26 times that of the Sun. With an effective temperature of about 7,700 K, it emits more than two thousand times the luminosity of the Sun.

9 Cassiopeiae has a number of faint companions listed in multiple star catalogues,[11] but they all appear to be at different distances[12] and none are thought to be gravitationally associated.[13]

References

  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. ^ Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27. Bibcode:2000A&A...355L..27H. doi:10.1888/0333750888/2862.
  3. ^ Gray, R. O.; Garrison, R. F. (December 1987). "The Early A-Type Stars: Refined MK Classification, Confrontation with Stroemgren Photometry, and the Effects of Rotation". Astrophysical Journal Supplement. 65: 581. Bibcode:1987ApJS...65..581G. doi:10.1086/191237.
  4. ^ a b Hoffleit, D.; Jaschek, C., eds. (1991). The Bright Star Catalogue. New Haven: Yale University Observatory. Bibcode:1991bsc..book.....H.
  5. ^ a b c Anders, F.; Khalatyan, A.; Chiappini, C.; Queiroz, A. B.; Santiago, B. X.; Jordi, C.; Girardi, L.; Brown, A. G. A.; Matijevič, G.; Monari, G.; Cantat-Gaudin, T.; Weiler, M.; Khan, S.; Miglio, A.; Carrillo, I.; Romero-Gómez, M.; Minchev, I.; De Jong, R. S.; Antoja, T.; Ramos, P.; Steinmetz, M.; Enke, H. (2019). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18". Astronomy and Astrophysics. 628: A94. arXiv:1904.11302. Bibcode:2019A&A...628A..94A. doi:10.1051/0004-6361/201935765. S2CID 131780028.
  6. ^ a b c 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.
  7. ^ a b Murphy, Simon J.; Corbally, Christopher J.; Gray, Richard O.; Cheng, Kwang-Ping; Neff, James E.; Koen, Chris; Kuehn, Charles A.; Newsome, Ian; Riggs, Quinlin (2015). "An Evaluation of the Membership Probability of 212 λ Boo Stars. I. A Catalogue". Publications of the Astronomical Society of Australia. 32. arXiv:1508.03633. Bibcode:2015PASA...32...36M. doi:10.1017/pasa.2015.34. S2CID 59405545.
  8. ^ Tetzlaff, N.; Neuhäuser, R.; Hohle, M. M. (October 12, 2010). "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun". Monthly Notices of the Royal Astronomical Society. 410 (1). Oxford University Press (OUP): 190–200. arXiv:1007.4883. Bibcode:2011MNRAS.410..190T. doi:10.1111/j.1365-2966.2010.17434.x. ISSN 0035-8711.
  9. ^ Abt, Helmut A.; Morrell, Nidia I. (July 1995). "The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars". The Astrophysical Journal Supplement Series. 99: 135. Bibcode:1995ApJS...99..135A. doi:10.1086/192182. ISSN 0067-0049.
  10. ^ Hauck, B.; Ballereau, D.; Chauville, J. (1998). "New lambda Bootis stars with a shell". Astronomy and Astrophysics Supplement Series. 128 (3): 429. arXiv:astro-ph/9709015. Bibcode:1998A&AS..128..429H. doi:10.1051/aas:1998154. S2CID 118881330.
  11. ^ Mason, Brian D.; et al. (December 2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog". The Astronomical Journal. 122 (6): 3466–3471. Bibcode:2001AJ....122.3466M. doi:10.1086/323920.
  12. ^ 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.
  13. ^ Eggleton, P. P.; Tokovinin, A. A. (3 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. S2CID 14878976.