U Lacertae

U Lacertae
Location of U Lacertae (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Lacerta
Right ascension 22h 47m 43.42677s[1]
Declination 55° 09′ 30.3036″[1]
Apparent magnitude (V) 9.40[2]
Characteristics
Spectral type M4epIab + B[3]
U−B color index +1.46[2]
B−V color index +2.34[2]
Variable type SRc[3]
Astrometry
Radial velocity (Rv)−68[4] km/s
Proper motion (μ) RA: −3.207 [5] mas/yr
Dec.: −3.150 [5] mas/yr
Parallax (π)0.3519 ± 0.0708 mas[5]
Distance2,750[6] pc
Absolute magnitude (MV)−5.6[7]
Details
Mass22[7] M☉
Radius1,013[8] R☉
Luminosity152,000[8] L☉
Temperature3,535[8] K
Other designations
U Lac, HIP 112545, PPM 411, GSC 03988-01641, IRC+50446, TYC 3988-1641-1, BD+54 2863, HD 215924, 2MASS J22474341+5509303, AAVSO 2243+54
Database references
SIMBADdata

U Lacertae is a spectroscopic binary star in the constellation Lacerta.

Despite being in the constellation of Lacerta, U Lacertae is considered to be a member of the Cepheus OB1 association.[9] It has been listed as a member of the open cluster ASCC 123.[10]

U Lacertae is a binary star consisting of a red supergiant and a small hot companion, similar to VV Cephei. The companion has been identified from a high excitation component in the spectrum and from radial velocity variations, but the orbit is unknown.[11]

A visual band light curve for U Lacertae, plotted from AAVSO data[12]

U Lacertae is a variable star classified as a semiregular variable.[3] The periodicity is uncertain but a main period of 150 days and a long secondary period of 550 – 690 days have been suggested.[13] A study of Hipparcos satellite photometry found an amplitude of 0.77 magnitudes and found no periodicity.[14] The General Catalogue of Variable Stars lists an amplitude of 2.7 magnitudes.[3]

Water masers have been detected around U Lacertae, common in the extended atmospheres of very luminous cool stars.[15]

See also

References

  1. ^ a b Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600.
  2. ^ a b c Ducati, J. R. (2002). "VizieR On-line Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues. 2237. Bibcode:2002yCat.2237....0D.
  3. ^ a b c d U Lac, database entry, The combined table of GCVS Vols I-III and NL 67-78 with improved coordinates, General Catalogue of Variable Stars Archived 2017-06-20 at the Wayback Machine, Sternberg Astronomical Institute, Moscow, Russia. Accessed on line November 12, 2010.
  4. ^ Gontcharov, G. A. (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. S2CID 119231169.
  5. ^ 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.
  6. ^ Reiter, Megan; Marengo, Massimo; Hora, Joseph L.; Fazio, Giovanni G. (2015). "A Spitzer/IRAC characterization of Galactic AGB and RSG stars". Monthly Notices of the Royal Astronomical Society. 447 (4): 3909. arXiv:1501.02749. Bibcode:2015MNRAS.447.3909R. doi:10.1093/mnras/stu2725. S2CID 118515353.
  7. ^ a b Stothers, R.; Leung, K. C. (1971). "Luminosities, masses and periodicities of massive red supergiants". Astronomy and Astrophysics. 10: 290. Bibcode:1971A&A....10..290S.
  8. ^ a b c Healy, Sarah; Horiuchu, Shunsaku; Colomer Moller, Marta; Milisavljevic, Dan; Tseng, Jeff; Bergin, Faith; Weil, Kathryn; Tanaka, Masaomi (2024). "Red supergiant candidates for multimessenger monitoring of the next Galactic supernova". Monthly Notices of the Royal Astronomical Society. 529 (4): 3630–3650. arXiv:2307.08785. Bibcode:2024MNRAS.529.3630H. doi:10.1093/mnras/stae738.
  9. ^ Garmany, C. D.; Stencel, R. E. (1992). "Galactic OB associations in the northern Milky Way Galaxy. I - Longitudes 55 deg to 150 deg". Astronomy and Astrophysics Supplement Series. 94: 211. Bibcode:1992A&AS...94..211G.
  10. ^ Zejda, M.; Paunzen, E.; Baumann, B.; Mikulášek, Z.; Liška, J. (2012). "Catalogue of variable stars in open cluster fields". Astronomy & Astrophysics. 548: A97. arXiv:1211.1153. Bibcode:2012A&A...548A..97Z. doi:10.1051/0004-6361/201219186. S2CID 54789717.
  11. ^ Burki, G.; Mayor, M. (1983). "Nineteen new spectroscopic binaries and the rate of binary stars among F-M supergiants". Astronomy and Astrophysics. 124: 256. Bibcode:1983A&A...124..256B.
  12. ^ "Download Data". aavso.org. AAVSO. Retrieved 1 October 2021.
  13. ^ Houk, N. (1963). "V1280 Sagttarii and the other long-period variables with secondary period". Astronomical Journal. 68: 253. Bibcode:1963AJ.....68..253H. doi:10.1086/108948.
  14. ^ Adelman, Saul J. (2001). "Stars with the Largest Hipparcos Photometric Amplitudes". Baltic Astronomy. 10 (4): 589. Bibcode:2001BaltA..10..589A. doi:10.1515/astro-2001-0403. S2CID 116386247.
  15. ^ Yoon, Dong-Hwan; Cho, Se-Hyung; Kim, Jaeheon; Yun, Young joo; Park, Yong-Sun (2014). "SiO and H2O Maser Survey toward Post-asymptotic Giant Branch and Asymptotic Giant Branch Stars". The Astrophysical Journal Supplement. 211 (1): 15. Bibcode:2014ApJS..211...15Y. doi:10.1088/0067-0049/211/1/15. S2CID 73561291.

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