U Lacertae

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U Lacertae
Lacerta constellation map.svg
Red circle.svg
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]
Distance 2,750 [6]   pc
Absolute magnitude  (MV)−5.6 [7]
Details
Mass 22 [7]   M☉
Radius 1,013 [8]   R☉
Luminosity 152,000 [8]   L☉
Temperature 3,535 [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
SIMBAD data

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 ULacLightCurve.png
A visual band light curve for U Lacertae, plotted from AAVSO data

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

Related Research Articles

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<span class="mw-page-title-main">27 Canis Majoris</span> Binary star system in the constellation Canis Major

27 Canis Majoris is a binary star system in the northern constellation of Canis Major, located approximately 1,700 light years away from the Sun. It has the variable star designation EW Canis Majoris; 27 Canis Majoris is the Flamsteed designation. This system is visible to the naked eye as a dim, blue-white hued star with an apparent visual magnitude of +4.65. It is moving away from the Earth with a heliocentric radial velocity of 16 km/s.

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<span class="mw-page-title-main">Zeta Cephei</span> Star in the constellation Cepheus

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<span class="mw-page-title-main">W Cephei</span> Variable star in the constellation Cepheus

W Cephei is a spectroscopic binary and variable star located in the constellation Cepheus. It is thought to be a member of the Cep OB1 stellar association at about 8,000 light years. The supergiant primary star is one of the largest known stars and as well as one of the most luminous red supergiants.

2 Vulpeculae is a binary star system in the northern constellation of Vulpecula, located around 1,800 light years away from the Sun. It is visible to the naked eye as a faint, blue-white hued star with an apparent visual magnitude of 5.43.

<span class="mw-page-title-main">V381 Cephei</span> Triple star system in the constellation Cepheus

V381 Cephei is a triple star system in the northern constellation of Cepheus. Its apparent magnitude is slightly variable between 5.5 and 5.7.

Chi<sup>2</sup> Orionis Star in the constellation Orion

Chi2 Orionis is a B-type blue supergiant star in the constellation of Orion. It has an apparent visual magnitude of 4.63 but being quite distant, and heavily extinguished it burns with the greatest absolute visual light magnitude among stars in Orion within the near reaches of the galaxy, 0.9 of a magnitude brighter than Rigel. Since 1943, the spectrum of this star has served as one of the stable anchor points by which other stars are classified. It is considered to be a member of the Gemini OB1 association.

<span class="mw-page-title-main">5 Lacertae</span> Star in the constellation Lacerta

5 Lacertae is a spectroscopic binary in the constellation Lacerta. Its apparent magnitude is 4.36.

4 Lacertae is a single blue supergiant star in the northern constellation Lacerta, located about 2,600 light years away. This object visible to the naked eye as a white-hued star with an apparent visual magnitude of 4.55. It is moving closer to the Earth with a heliocentric radial velocity of −26 km/s. This star is a suspected member of the Lac OB1 association.

<span class="mw-page-title-main">V424 Lacertae</span> Star in the constellation Lacerta

V424 Lacertae is a red supergiant variable star in the constellation Lacerta. It is a member of the Lacerta OB1 stellar association.

<span class="mw-page-title-main">AX Circini</span> Binary star system in the constellation Circinus

AX Circini is a binary star system in the southern constellation of Circinus. It has a nominal magnitude of 5.91, which is bright enough to be visible to the naked eye. Based upon an annual parallax shift of 1.7 mas, it is located roughly 1,900 light-years from the Earth. The system is moving closer with a heliocentric radial velocity of −21 km/s.

<span class="mw-page-title-main">KQ Puppis</span> Binary star in the constellation Puppis

KQ Puppis is a spectroscopic binary located about 2,700 light-years from Earth in the constellation Puppis. A red supergiant star and a B-type main-sequence star orbit each other every 27 years. Its apparent magnitude varies between 4.82 and 5.17, making it faintly visible to the naked eye.

<span class="mw-page-title-main">V1073 Scorpii</span> Variable star in the constellation Scorpius

V1073 Scorpii is a variable star in the constellation Scorpius. It has a non-Greek Bayer designation of k Scorpii. The star has a blue-white hue and is visible to the naked eye with an apparent visual magnitude that fluctuates around +4.87. Parallax measurements yield a distance estimate of approximately 2,920 ly (896 pc) from the Sun, and it is drifting further away with a radial velocity of +7 km/s. It has an absolute magnitude of −6.8

<span class="mw-page-title-main">16 Lacertae</span> Triple star system in the constellation Lacerta

16 Lacertae is a triple star system in the northern constellation of Lacerta, located about 1,580 light years from the Sun. It has the variable star designation EN Lacertae; 16 Lacertae is the Flamsteed designation. This system is visible to the naked eye as a faint blue-white hued star with a maximum apparent visual magnitude of +5.587. It is moving closer to the Earth with a heliocentric radial velocity of –12 km/s.

<span class="mw-page-title-main">V419 Cephei</span> Star in the constellation Cepheus

V419 Cephei is an irregular variable star in the constellation of Cepheus with an apparent magnitude that varies between 6.54 and 6.89.

Psi<sup>2</sup> Orionis Spectroscopic binary system in the constellation of Orion

Psi2 Orionis a binary star system in the equatorial constellation of Orion. It has an apparent visual magnitude of 4.6, indicating that it is visible to the naked eye. Based upon an annual parallax shift of 2.87 mass, it is roughly 1,100 light years distant from the Sun.

<span class="mw-page-title-main">12 Lacertae</span> Star in the constellation Lacerta

12 Lacertae is a wide binary star system in the northern constellation of Lacerta, located roughly 1,260 light years away from the Sun based on parallax. It is visible to the naked eye as a dim, blue-white hued point of light with a baseline apparent visual magnitude of 5.23. The system is drifting closer to the Earth with a mean heliocentric radial velocity of –12.5. It is a probable member of the I Lacertae OB association.

<span class="mw-page-title-main">SZ Tauri</span> Variable star in Taurus

SZ Tauri is a variable star in the equatorial constellation of Taurus. The brightness of this star varies from an apparent visual magnitude of 6.39 down to 6.69 with a period of 3.149 days, which is near the lower limit of visibility to the naked eye. The distance to this star is approximately 2,070 light years based on parallax measurements. There is some indication this may be a binary system, but the evidence is inconclusive.

References

  1. 1 2 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. 1 2 3 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. 1 2 3 4 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. 1 2 3 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. 1 2 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. 1 2 3 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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