X Crucis

Last updated
X Crucis
XCruLightCurve.png
A light curve for X Crucis, plotted from TESS data [1]
Observation data
Epoch J2000       Equinox J2000
Constellation Crux
Right ascension 12h 46m 22.2678s [2]
Declination −59° 07′ 29.120″ [2]
Apparent magnitude  (V)8.1 - 8.7 [3]
Characteristics
Spectral type G1Ib [4]
B−V color index +0.87 [5]
Variable type δ Cep [3]
Astrometry
Radial velocity (Rv)-25.0 [6]  km/s
Proper motion (μ)RA: -8.2 [7]   mas/yr
Dec.: -0.9 [7]   mas/yr
Parallax (π)0.5235 ± 0.0459  mas [8]
Distance 6,200 ± 500  ly
(1,900 ± 200  pc)
Absolute magnitude  (MV)−3.9 [9]
Details
Mass 4.3 [9]   M☉
Radius 50 [10]   R☉
Luminosity 2,884 [9]   L☉
Surface gravity (log g)1.69 [9]   cgs
Temperature 5,180 - 6,029 [11]   K
Other designations
X  Crucis, X Cru, HD  110945, SAO  240231, CPD −58°4490, 2MASS  J12462227-5907290, TYC  8659-1943-1, AN  186.1906, GCRV  63538, PPM  341282, AAVSO  1240-58, CD −58°4731, GSC  08659-01943, CPC  20 3918, HV  1298, Gaia DR2 6059764002146656128
Database references
SIMBAD data

X Crucis is a classical Cepheid variable star in the southern constellation of Crux.

X Crucis is a pulsating variable star with am extremely regular amplitude and period. Its apparent magnitude varies from 8.1 to 8.7 every 6.22 days. This type of variable is known as a Cepheid after δ Cephei, the first example to be discovered. X Crucis is a population I star and so is a classical or type I Cepheid variable, to be distinguished from older low-mass stars called type II Cepheid variables. [3]

Classical Cepheids pulsate radially so that their size varies. X Crucis pulsates in its fundamental mode and its properties indicate that it is crossing the instability strip for the third time as its evolves back to cooler temperatures. [9] Its radius varies by about 5 R☉ during each cycle, approximately 8% of its mean radius. At the same time its temperature varies between 5,180 and 6,029 K. The radius and temperature do not vary in sync, with the smallest size occurring as the temperature is approaching its maximum. The brightness increases rapidly to a maximum when the star is hottest, then decreases more slowly. This is one of the properties that indicate fundamental mode pulsation. [10] [11]

Related Research Articles

<span class="mw-page-title-main">W Sagittarii</span> Star in the constellation Sagittarius

W Sagittarii is a multiple star system star in the constellation Sagittarius, and a Cepheid variable star.

<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">HD 84810</span> Star in the constellation Carina

HD 84810, also known as l Carinae, is a star in the southern constellation of Carina. Its apparent magnitude varies from about 3.4 to 4.1, making it readily visible to the naked eye and one of the brightest members of Carina. Based upon parallax measurements, it is approximately 1,600 light-years from Earth.

<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">RS Puppis</span> Variable star in the constellation Puppis

RS Puppis is a Cepheid variable star around 6,000 ly away in the constellation of Puppis. It is one of the biggest and brightest known Cepheids in the Milky Way galaxy and has one of the longest periods for this class of star at 41.5 days.

<span class="mw-page-title-main">DL Crucis</span> Star in the constellation Crux

DL Crucis is a variable star in the constellation Crux.

<span class="mw-page-title-main">TT Aquilae</span> Star in the constellation Aquila

TT Aquilae is a Classical Cepheid variable star in the constellation Aquila.

<span class="mw-page-title-main">V602 Carinae</span> Star in the constellation Carina

V602 Carinae is a red supergiant and variable star of spectral type of M3 in the constellation Carina. It is one of largest known stars.

<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">BG Crucis</span> Star system in the Crux constellation

BG Crucis is a suspected binary star system in the southern constellation of Crux. It is visible to the naked eye as a faint yellow-white hued point of light with an apparent visual magnitude that fluctuates around 5.49. The system is located at a distance of approximately 1,830 light years from the Sun based on parallax, and is drifting closer with a radial velocity of −19 km/s.

<span class="mw-page-title-main">S Crucis</span> Variable star in the constellation Crux

S Crucis is a star in the constellation Crux. A Cepheid variable, its apparent magnitude ranges from 6.22 to 6.92 over 4.68997 d. It is a yellow-white supergiant that pulsates between spectral types F6Ib-II and G1Ib-II.

<span class="mw-page-title-main">R Crucis</span> Variable star in the constellation Crux

R Crucis is a variable star in the southern constellation of Crux. It has a yellow-white hue and is often too faint to see with the naked eye, having an apparent visual magnitude that fluctuates around 6.89. This object is located at a distance of approximately 1,600 light years from the Sun based on parallax, but it is drifting closer with a radial velocity of −13.5 km/s.

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

W Crucis is a single-lined eclipsing variable star system in the constellation Crux. It has a spectral class of F8/G1Ia/abe indicating a yellow supergiant with emission lines in its spectrum.

<span class="mw-page-title-main">S Vulpeculae</span> Variable star in the constellation Vulpecula

S Vulpeculae is a variable star located in the constellation Vulpecula. A supergiant star, it is around 382 times the diameter of the Sun.

<span class="mw-page-title-main">SV Vulpeculae</span> Star in the constellation Vulpecula

SV Vulpeculae is a classical Cepheid variable star in the constellation Vulpecula. It is a supergiant at a distance of 8,700 light years.

<span class="mw-page-title-main">RU Camelopardalis</span> Star in the constellation Camelopardalis

RU Camelopardalis, or RU Cam, is a W Virginis variable in the constellation of Camelopardalis. It is also a Carbon star, which is very unusual for a Cepheid variable.

<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">AZ Phoenicis</span> A type variable star in the constellation Phoenix

AZ Phoenicis is a variable star in the constellation of Phoenix. It has an average visual apparent magnitude of 6.47, so it is at the limit of naked eye visibility. From parallax measurements by the Gaia spacecraft, it is located at a distance of 322 light-years from Earth. Its absolute magnitude is calculated at 1.65.

<span class="mw-page-title-main">Iota Mensae</span> Star in the constellation Mensa

Iota Mensae is a single star about 880 light years away in the faint constellation Mensa. It has a very slightly variable apparent magnitude of 6.0, making it visible with the naked eye under good skies.

References

  1. ↑ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 8 December 2021.
  2. 1 2 Hog, E.; Kuzmin, A.; Bastian, U.; Fabricius, C.; Kuimov, K.; Lindegren, L.; Makarov, V. V.; Roeser, S. (1998). "The TYCHO Reference Catalogue". Astronomy and Astrophysics. 335: L65. Bibcode:1998A&A...335L..65H.
  3. 1 2 3 Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1. Bibcode:2009yCat....102025S.
  4. ↑ Houk, Nancy (1979). Michigan catalogue of two-dimensional spectral types for the HD stars. Vol. 1. Ann Arbor: University of Michigan. Bibcode:1978mcts.book.....H.
  5. ↑ Dean, J.F. (1977). "B, V, I, photometry of Southern Cepheids". University of Michigan Catalogue of Two-dimensional Spectral Types for the HD Stars. Volume I. Declinations -90_ to -53_ƒ0. Ann Arbor: University of Michigan. Bibcode:1975mcts.book.....H.
  6. ↑ Evans, D. S. (1967). "The Revision of the General Catalogue of Radial Velocities". Determination of Radial Velocities and Their Applications. 30: 57. Bibcode:1967IAUS...30...57E.
  7. 1 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.
  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.
  9. 1 2 3 4 5 Opolski, A. (1984). "Observational determination of pulsation modes and photometric masses of Cepheid variables". Acta Astronomica. 34: 225. Bibcode:1984AcA....34..225O.
  10. 1 2 Tsvetkov, Ts. G. (1988). "Absolute and relative amplitudes of variations in radius of classical Cepheids". Astrophysics and Space Science. 150 (2): 223–234. Bibcode:1988Ap&SS.150..223T. doi:10.1007/BF00641718. S2CID   120067995.
  11. 1 2 Pel, J. W. (1978). "Intrinsic colours and physical properties of Cepheids". Astronomy and Astrophysics. 62: 75. Bibcode:1978A&A....62...75P.
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.