V1401 Aquilae

Last updated
V1401 Aquilae
V1401AqlLightCurve.png
The visual band light curve of V1401 Aquilae, adapted from Waelkens & Burnet(1985) [1]
Observation data
Epoch J2000.0       Equinox J2000.0
Constellation Aquila
Right ascension 20h 05m 05.41344s [2]
Declination −11° 35′ 57.8964″ [2]
Apparent magnitude  (V)6.38 [3] (6.18 to 6.55) [4]
Characteristics
Spectral type F2II [5]
B−V color index 0.543±0.023 [3]
Variable type SRd [4]
Astrometry
Radial velocity (Rv)−12.1±2.9 [3]  km/s
Proper motion (μ)RA: −2.585 [2]   mas/yr
Dec.: +15.629 [2]   mas/yr
Parallax (π)1.3722 ± 0.0441  mas [2]
Distance 2,380 ± 80  ly
(730 ± 20  pc)
Details
Mass 4.1 [6]   M☉
Radius 35 [2]   R☉
Luminosity 656 [7]
1,309 [2]   L☉
Surface gravity (log g)1.49±0.14 [8]   cgs
Temperature 6,192±90 [8]   K
Metallicity [Fe/H]−1.12±0.08 [8]   dex
Other designations
V1401 Aql, BD−12°5641, HD  190390, HIP  98910, HR  7671, SAO  163245, WDS J20051-1136A [9]
Database references
SIMBAD data

V1401 Aquilae is a single, [10] semi-regular pulsating star in the equatorial constellation of Aquila. It has the designation HD 190390 from the Henry Draper Catalogue , and was formerly designated 64 Sagittarii. [11] The evolutionary status of the star is unclear, and it has been classified as a post-AGB object, a UU Herculis variable, or belonging to the W Virginis variable subclass of the type II Cepheids. It is dimly visible to the naked eye with an apparent visual magnitude that fluctuates around 6.38. [3] Based on parallax measurements, it is located at a distance of approximately 2,380  light years. [2] It lies 21.5° from the galactic plane. [12]

The variability of this star was announced by W. Strohmeier and associates in 1965. [13] C. Waelkens and M. Burnet in 1985 found an irregular photometric variation with a period of around a month and suggested it is a candidate UU Herculis variable. [14] J. D. Fernie in 1986 confirmed the variability and tentatively identified periods of 28.4 and 11.8 days. He found a very low gravity with shell-like features, suggesting potential mass loss. [15] An analysis of the chemical composition by R. E. Luck and associates in 1990 found a mild enhancement of s-process elements as well as lithium, indicating it may have evolved from a lithium-rich giant. [16]

The stellar classification of V1401 Aql is F2II, [5] matching an F-type bright giant. There is strong evidence that this star belongs to the population II cepheids, and it may be a W Virginis variable. [7] On the Hertzsprung–Russell diagram it lies on the blue (hot) side of the Cepheid instability strip for population II stars. [10] Membership in the UU Herculis variable class seems less likely since it has a relatively normal radial velocity and no infrared excess has been detected. [7] The pulsation period of 28.6 days has been confirmed, but the pulsational behavior of this star is complex and it is not successfully modeled using a simple harmonic radial pulsation. [10]

The star is strongly metal deficient by a factor of 40, meaning the abundances of higher mass elements is much lower than in the Sun. There is a mild enhancement of s-process elements, although this is not considered to be intrinsic. Some investigators have suspected the star to be in an evolutionary stage following the asymptotic giant branch, but this is not confirmed based on chemical abundances. [7]

Related Research Articles

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

Zeta Geminorum is a bright star with cluster components, distant optical components and a likely spectroscopic partner in the zodiac constellation of Gemini — in its south, on the left 'leg' of the twin Pollux. It is a classical Cepheid variable star, of which over 800 have been found in our galaxy. As such its regular pulsation and luminosity and its relative proximity means the star is a useful calibrator in computing the cosmic distance ladder. Based on parallax measurements, it is approximately 1,200 light-years from the Sun.

<span class="mw-page-title-main">X Sagittarii</span> Variable star and possible binary star system in the constellation Sagittarius

X Sagittarii is a variable star and candidate binary star system in the southern constellation of Sagittarius, near the western constellation boundary with Ophiuchus. It has a yellow-white hue and is visible to the naked eye with an apparent visual magnitude that fluctuates around 4.54. The star is located at a distance of approximately 950 light years from the Sun based on parallax, and is drifting closer with a radial velocity of −10 km/s. The star has an absolute magnitude of around −2.85.

<span class="mw-page-title-main">RV Tauri</span> Star in the constellation Taurus

RV Tauri is a star in the constellation Taurus. It is a yellow supergiant and is the prototype of a class of pulsating variables known as RV Tauri variables. It is a post-AGB star and a spectroscopic binary about 4,700 light years away.

<span class="mw-page-title-main">RV Tauri variable</span> Class of luminous variable star

RV Tauri variables are luminous variable stars that have distinctive light variations with alternating deep and shallow minima.

<span class="mw-page-title-main">HD 95109</span> Star in the constellation Carina

HD 95109 is a Classical Cepheid variable, a type of variable star, in the constellation Carina. Its apparent magnitude is 6.86.

<span class="mw-page-title-main">Y Carinae</span> Star in the constellation Carina

Y Carinae is a Classical Cepheid variable, a type of variable star, in the constellation Carina. Its apparent magnitude varies from 7.53 to 8.48.

<span class="mw-page-title-main">V Centauri</span> Variable star in the constellation Centaurus

V Centauri is a Classical Cepheid variable, a type of variable star, in the constellation Centaurus. It is approximately 2,350 light-years away based on parallax.

<span class="mw-page-title-main">HR 4049</span> Protoplanetary nebula in the constellation Antlia

HR 4049, also known as HD 89353 and AG Antliae, is a binary post-asymptotic-giant-branch (post-AGB) star in the constellation Antlia. A very metal-poor star, it is surrounded by a thick unique circumbinary disk enriched in several molecules. With an apparent magnitude of about 5.5, the star can readily be seen with the naked eye under ideal conditions. It is located approximately 1,700 parsecs (5,500 ly) distant.

<span class="mw-page-title-main">89 Herculis</span> Star in the constellation Hercules

89 Herculis is a binary star system located about 4,700 light years away from the Sun in the northern constellation of Hercules. It is visible to the naked eye as a faint, fifth magnitude star. The system is moving closer to the Earth with a heliocentric radial velocity of −28.5 km/s.

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

W Virginis is the prototype W Virginis variable, a subclass of the Cepheid variable stars. It is located in the constellation Virgo, and varies between magnitudes 9.46 and 10.75 over a period of approximately 17 days.

<span class="mw-page-title-main">104 Herculis</span> Star in the constellation Hercules


104 Herculis is a solitary variable star located around 560 light years away from the Sun in the northern constellation of Hercules. It has the variable star designation V669 Herculis and the Bayer designation A Herculis, while 104 Herculis is the Flamsteed designation. This object is visible to the naked eye as a dim, red-hued point of light with a baseline apparent visual magnitude of 4.96. It is moving closer to the Earth with a heliocentric radial velocity of −1.2 km/s.

<span class="mw-page-title-main">R Sagittae</span> Star in the constellation Sagitta

R Sagittae is an RV Tauri variable star in the constellation Sagitta that varies from magnitude 8.0 to 10.5 in 70.77 days. It is a post-AGB low mass yellow supergiant that varies between spectral types G0Ib and G8Ib as it pulsates. Its variable star designation of "R" indicates that it was the first star discovered to be variable in the constellation. It was discovered in 1859 by Joseph Baxendell, though classified as a semi regular variable until RV Tauri variables were identified as a distinct class in 1905.

<span class="mw-page-title-main">S Trianguli Australis</span> Variable star in the constellation Triangulum Australe

S Trianguli Australis is a yellow-white hued variable star in the constellation Triangulum Australe. It is a dim star near the lower limit of visibility with the naked eye, having a typical apparent visual magnitude of 6.41. Based upon an annual parallax shift of 1.08 mas, it is located 3,030 light years from the Earth.

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

W Aquilae is a variable star in the constellation of Aquila. It is a type of evolved star known as an S-type star. Due to its relatively close distance of 1,200 light-years and equatorial location, it is easy to observe and heavily studied.

<span class="mw-page-title-main">S Cassiopeiae</span> Star in the constellation Cassiopeia

S Cassiopeiae is a Mira variable and S-type star in the constellation Cassiopeia. It is an unusually cool star, rapidly losing mass and surrounded by dense gas and dust producing masers.

<span class="mw-page-title-main">SX Centauri</span> Supergiant variable star in the constellation Centaurus

SX Centauri is a variable star in the constellation Centaurus. An RV Tauri variable, its light curve alternates between deep and shallow minima, varying its apparent magnitude from 9.1 to 12.4. From the period-luminosity relationship, it is estimated to be around 1.6 kpc from Earth. Gaia Data Release 2 gives a parallax of 0.2175 mas, corresponding to distance of about 4,600 pc.

<span class="mw-page-title-main">HR 3831</span> Binary star system in the constelaltion Vela

HR 3831, also known as HD 83368, is a binary star system in the southern constellation of Vela at a distance of 233 light years. This object is barely visible to the naked eye as a dim, blue star with an apparent visual magnitude of 6.232. It is approaching the Earth with a heliocentric radial velocity of 4.0±0.3 km/s.

<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.

<span class="mw-page-title-main">FG Virginis</span> Variable star in the constellation Virgo

FG Virginis is a well-studied variable star in the equatorial constellation of Virgo. It is a dim star, near the lower limit of visibility to the naked eye, with an apparent visual magnitude that ranges from 6.53 down to 6.58. The star is located at a distance of 273.5 light years from the Sun based on parallax measurements, and is drifting further away with a radial velocity of +16 km/s. Because of its position near the ecliptic, it is subject to lunar occultations.

<span class="mw-page-title-main">X Cygni</span> Variable star in the constellation Cygnus

X Cygni is a variable star in the northern constellation of Cygnus, abbreviated X Cyg. This is a Delta Cephei variable that ranges in brightness from an apparent visual magnitude of 5.85 down to 6.91 with a period of 16.386332 days. At it brightest, this star is dimly visible to the naked eye. The distance to this star is approximately 628 light years based on parallax measurements. It is drifting further away with a radial velocity of 8.1 km/s. This star is a likely member of the open cluster Ruprecht 173.

References

  1. ↑ Waelkens, C.; Burnet, M. (October 1985). "The Periodicity of the Photometric Variations of HR 7671 (HD 190390)". Information Bulletin on Variable Stars. 2808 (1): 1. Bibcode:1985IBVS.2808....1W . Retrieved 22 October 2021.
  2. 1 2 3 4 5 6 7 8 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.
  3. 1 2 3 4 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv: 1108.4971 . Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. S2CID   119257644.
  4. 1 2 Samus', N. N; et al. (2017). "General catalogue of variable stars". Astronomy Reports. GCVS 5.1. 61 (1): 80. Bibcode:2017ARep...61...80S. doi:10.1134/S1063772917010085. S2CID   125853869.
  5. 1 2 Houk, N.; Swift, C. (1999). "Michigan catalogue of two-dimensional spectral types for the HD Stars". Michigan Spectral Survey. 5. Bibcode:1999MSS...C05....0H.
  6. ↑ 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.
  7. 1 2 3 4 Reyniers, M.; Cuypers, J. (March 2005). "The evolutionary status of the bright high-latitude supergiant HD 190390". Astronomy and Astrophysics. 432 (2): 595–608. arXiv: astro-ph/0411493 . Bibcode:2005A&A...432..595R. doi:10.1051/0004-6361:20042097. S2CID   1645692.
  8. 1 2 3 Arentsen, Anke; et al. (July 2019). "Stellar atmospheric parameters for 754 spectra from the X-shooter Spectral Library". Astronomy & Astrophysics. 627: 14. arXiv: 1907.06391 . Bibcode:2019A&A...627A.138A. doi:10.1051/0004-6361/201834273. S2CID   196621431. A138.
  9. ↑ "V1401 Aql". SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 2021-02-23.
  10. 1 2 3 van Winckel, H.; et al. (October 2009). "Post-AGB stars with hot circumstellar dust: binarity of the low-amplitude pulsators". Astronomy and Astrophysics. 505 (3): 1221–1232. arXiv: 0906.4482 . Bibcode:2009A&A...505.1221V. doi:10.1051/0004-6361/200912332. S2CID   119299698.
  11. ↑ Wagman, M. (August 1987). "Flamsteed's Missing Stars". Journal for the History of Astronomy. 18 (3): 209–223. Bibcode:1987JHA....18..209W. doi:10.1177/002182868701800305. S2CID   118445625.
  12. ↑ Trams, N. R.; et al. (1991). "Post AGB candidates-Selection and IR properties". Astronomy and Astrophysics Supplement Series. 87: 361–382. Bibcode:1991A&AS...87..361T.
  13. ↑ Strohmeier, W.; et al. (February 1965). "Bright Southern BV-Stars". Information Bulletin on Variable Stars. 81: 1. Bibcode:1965IBVS...81....1S.
  14. ↑ Waelkens, C.; Burnet, M. (October 1985). "The Periodicity of the Photometric Variations of HR 7671 (HD 190390)". Information Bulletin on Variable Stars. 2808: 1. Bibcode:1985IBVS.2808....1W.
  15. ↑ Fernie, J. D. (February 1986). "HR 7671: Another UU Herculis Star?". Astrophysical Journal. 301: 302. Bibcode:1986ApJ...301..302F. doi: 10.1086/163899 .
  16. ↑ Luck, R. Earle; et al. (July 1990). "Chemical Compositions of Four High-Latitude A--F Supergiants". Astrophysical Journal. 357: 188. Bibcode:1990ApJ...357..188L. doi: 10.1086/168904 .
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.