R Chamaeleontis

Last updated
R Chamaeleontis
RChaLightCurve.png
Visual band light curves for R Chamaeleontis. The upper plot shows AAVSO data, [1] and the lower plot shows ASAS-SN data [2] folded with the star's period of 338 days. [3]
Observation data
Epoch J2000.0        Equinox J2000.0 (ICRS)
Constellation Chamaeleon
Right ascension 08h 21m 46.4589s [4]
Declination −76° 21′ 18.302″ [4]
Apparent magnitude  (V)7.5 - 14.1 [5]
Characteristics
Spectral type M4e-M8e [5]
Variable type Mira [5]
Astrometry
Radial velocity (Rv)−21.893±6.065 [6]  km/s
Proper motion (μ)RA: −16.420  mas/yr [4]
Dec.: +14.578  mas/yr [4]
Parallax (π)1.0761 ± 0.0617  mas [4]
Distance 3,000 ± 200  ly
(930 ± 50  pc)
Details
Mass 2.5 [7]   M☉
Radius 588 [4]   R☉
Luminosity 3,908 [8]   L☉
Surface gravity (log g)−0.77 [7]   cgs
Temperature 2,569 [7]   K
Metallicity [Fe/H]0.00 [7]   dex
Other designations
R Cha, HD  71793, TYC  9394-1962-1, GSC  09394-01962
Database references
SIMBAD data

R Chamaeleontis (abbreviated to R Cha), also known as HD 71793, is a Mira variable located in the southern circumpolar constellation Chamaeleon. It has an apparent magnitude that ranges from 7.5 to 14.1, which is below the limit for naked eye visibility. Gaia DR3 parallax measurements place it about 3,000 light years away and it is currently approaching with a heliocentric radial velocity of 22  km/s .

This star was first reported to be variable in 1906, the first to be discovered in the constellation of Chamaeleon. [9]

R Cha has a stellar classification that has been recorded between M4e near maximum and M8e near minimum. [10] It is an asymptotic giant branch star that has exhausted its core hydrogen and helium and is now fusing hydrogen and helium in separate shells outside its core. [11] It has expanded to about 588  R☉ although this varies as it pulsates. [4] It radiates about 4,000  L☉ despite its relatively low surface temperature around 2,500  K . The effective temperature also varies as the star pulsates, corresponding to the change in the spectral class. [12]

Related Research Articles

<span class="mw-page-title-main">T Andromedae</span> Variable star in the constellation Andromeda

T Andromedae is a variable star of the Mira type in the constellation Andromeda. Like all the stars of this kind, T And is a cool asymptotic giant branch star of spectral type M4e-M7.5e. Its brightness varies periodically, completing a cycle in 281 days. The peak luminosity, however, is different every variability cycle, but can reach a peak magnitude mv=7.70.

<span class="mw-page-title-main">U Aquarii</span> Star in the constellation of Aquarius

U Aquarii, abbreviated U Aqr, is a variable star in the equatorial constellation of Aquarius. It is invisible to the naked eye, having an apparent visual magnitude that ranges from 10.6 down to as low as 15.9. Based on parallax measurements, the distance to this star is approximately 38 kly (12 kpc). In 1990, W. A. Lawson and associates provided a distance estimate of 43 kly (13.2 kpc) based on the assumption of a bolometric magnitude of −5. It appears to lie several kiloparsecs below the galactic plane, and thus may belong to an old stellar population.

<span class="mw-page-title-main">Z Apodis</span> Variable star in the constellation Apus

Z Apodis (Z Aps) is a variable star in the constellation of Apus. It has an apparent visual magnitude which varies between 10.8 and 12.8, over a period of 39.37 days. Although described in the General Catalogue of Variable Stars as a cataclysmic variable star, it appears that it is a pulsating variable star, and has been classed as an RV Tauri variable star, type RVa. Other sources classify it is a type II Cepheid.

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

R Reticuli, also listed under the duplicate variable star designation S Reticuli, is a Mira variable star in the southern constellation Reticulum. It is an aging red giant star on the asymptotic giant branch with a stellar classification that varies between M4e to M7.5e, being hottest near maximum visual magnitude. The brightness of the star varies between apparent visual magnitudes 6.35 and 14.2 with an average period of 281.08±0.58 d. The mean maximum magnitude is 7.57 and the mean minimum magnitude 13.80.

<span class="mw-page-title-main">HD 183144</span> Suspected variable star in the constellation Aquila

HD 183144 is suspected variable star in the equatorial constellation of Aquila. It is a hot giant star about 1,130 light years away.

HD 156768 is a double star in the southern constellation of Ara, with a combined apparent magnitude of 5.86. The brighter component is a sixth magnitude bright giant or supergiant star with a stellar classification of G8Ib/II. The magnitude 9.6 companion lies at an angular separation of 1.81″ along a position angle of 184°.

HD 118508 is a suspected variable star in the northern constellation of Boötes. Its apparent magnitude may vary with an amplitude of 0.04, discovered during a search for small-amplitude red variables. It is a red giant about 552 light years away.

<span class="mw-page-title-main">HD 135530</span> Suspected variable star in the northern constellation Boötes

HD 135530 is a suspected variable star in the northern constellation of Boötes.

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

W Andromedae is a variable star in the constellation of Andromeda. It is classified as a Mira variable and S-type star, and varies from an apparent visual magnitude of 14.6 at minimum brightness to a magnitude of 6.7 at maximum brightness, with a period of approximately 397.3 days. The star is losing mass due to stellar winds at a rate of 2.79×10−7M☉/yr.

<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.

<span class="mw-page-title-main">Zeta Chamaeleontis</span> Variable star in the constellation Chamaeleon

Zeta Chamaeleontis, Latinized from ζ Chamaeleontis, is a star located in the constellation Chamaeleon. Located around 540 light-years distant, it shines with a luminosity approximately 522 times that of the Sun and has a surface temperature of 15,655 K.

<span class="mw-page-title-main">R Equulei</span> Star in the constellation of Equuleus

R Equulei is a class M Mira variable star in the constellation Equuleus. Its brightness varies between a minimum magnitude of 15.0 to a maximum of 8.7 with an average period of 261 days.

<span class="mw-page-title-main">Eta Piscis Austrini</span> Star in the constellation Piscis Austrinus

Eta Piscis Austrini is binary star system in the southern constellation of Piscis Austrinus. As of 2000, the two components had an angular separation of 1.818 arc seconds along a position angle of 113.4°. The pair have a combined apparent visual magnitude of +5.43, which is bright enough to be seen with the naked eye. Based upon an annual parallax shift of 3.99 mas as seen from the Earth, the system is located roughly 820 light years from the Sun.

<span class="mw-page-title-main">S Canis Minoris</span> Variable star in the constellation Canis Minor

S Canis Minoris is a variable star in the equatorial constellation Canis Minor. It has a peak apparent visual magnitude of 6.5, so not normally visible to the naked eye. The star is located at a distance of approximately 1,360 light-years from the Sun based on stellar parallax, and is drifting further away with a radial velocity of about +68 km/s.

ι2 Muscae, Latinised as Iota2 Muscae, is a blue-white-hued star in the southern constellation Musca, near the constellation's southern border with Chamaeleon. It has an apparent visual magnitude of 6.62, which is just below the normal limit of stellar brightness visible to the naked eye. Based upon parallax measurements, it is located around 492 light-years from the Sun. It is a member of the Hyades Stream, but is not part of the Hyades or Praesepe open clusters.

<span class="mw-page-title-main">R Ursae Minoris</span> Star in the constellation Ursa Minor

R Ursae Minoris is a star in the constellation Ursa Minor. A red giant of spectral type M7IIIe, it is a semiregular variable ranging from magnitude 8.5 to 11.5 over a period of 325 days.

<span class="mw-page-title-main">BI Cygni</span> Star in the constellation Cygnus

BI Cygni(BI Cyg, IRC +40408, BD+36 4025) is a red supergiant in the constellation Cygnus. It is an irregular variable star with a maximum brightness of magnitude 8.4 and a minimum of magnitude 9.9. It is considered a member of the stellar Cygnus OB1 association, its distance is around 2,600 parsecs (8,500 ly) of the Solar System. It is less than a degree south of another variable red supergiant, BC Cygni.

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

NR Vulpeculae is a red supergiant and irregular variable star in the constellation Vulpecula. It has an effective temperature around 4,000 K, a radius of 553 times larger than the sun, which means that if it were in the place of the Sun, its surface would reach beyond Mars's orbit. Consequently, NR Vulpeculae is also a luminous star, radiating 111,000 - 223,000 times as much energy as the sun. It is considered a likely member of the Vulpecula OB1 stellar association.

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

HD 62058, is a variable star in the constellation Puppis. It is a rare yellow hypergiant and a candidate member of the open cluster NGC 2439. It is also an MK spectral standard for the class G2 0-Ia.

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

R Fornacis is a Mira variable and carbon star located in the constellation Fornax. It is around 1,800 light years away based on parallax measurements.

References

  1. ↑ "Download Data". aavso.org. AAVSO. Retrieved 8 March 2023.
  2. ↑ "ASAS-SN Variable Stars Database". ASAS-SN Variable Stars Database. ASAS-SN. Retrieved 8 March 2023.
  3. ↑ "R Cha". The International Variable Star Index. AAVSO. Retrieved 9 March 2023.
  4. 1 2 3 4 5 6 7 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.
  5. 1 2 3 Samus’, N. N.; Kazarovets, E. V.; Durlevich, O. V.; Kireeva, N. N.; Pastukhova, E. N. (January 2017). "General catalogue of variable stars: Version GCVS 5.1". Astronomy Reports. 61 (1): 80–88. Bibcode:2017ARep...61...80S. doi:10.1134/S1063772917010085. eISSN   1562-6881. ISSN   1063-7729. S2CID   125853869.
  6. ↑ Kunder, Andrea; Kordopatis, Georges; Steinmetz, Matthias; Zwitter, Tomaž; McMillan, Paul J.; Casagrande, Luca; Enke, Harry; Wojno, Jennifer; Valentini, Marica; Chiappini, Cristina; Matijevič, Gal; Siviero, Alessandro; De Laverny, Patrick; Recio-Blanco, Alejandra; Bijaoui, Albert; Wyse, Rosemary F. G.; Binney, James; Grebel, E. K.; Helmi, Amina; Jofre, Paula; Antoja, Teresa; Gilmore, Gerard; Siebert, Arnaud; Famaey, Benoit; Bienaymé, Olivier; Gibson, Brad K.; Freeman, Kenneth C.; Navarro, Julio F.; Munari, Ulisse; et al. (2017). "The Radial Velocity Experiment (RAVE): Fifth Data Release". The Astronomical Journal. 153 (2): 75. arXiv: 1609.03210 . Bibcode:2017AJ....153...75K. doi: 10.3847/1538-3881/153/2/75 . S2CID   118835808.
  7. 1 2 3 4 Anders, F.; Khalatyan, A.; Queiroz, A. B. A.; Chiappini, C.; Ardevol, J.; Casamiquela, L.; Figueras, F.; Jimenez-Arranz, O.; Jordi, C.; Monguio, M.; Romero-Gomez, M.; Altamirano, D.; Antoja, T.; Assaad, R.; Cantat-Gaudin, T.; Castro-Ginard, A.; Enke, H.; Girardi, L.; Guiglion, G.; Khan, S.; Luri, X.; Miglio, A.; Minchev, I.; Ramos, P.; Santiago, B. X.; Steinmetz, M. (2022). "VizieR Online Data Catalog: StarHorse2, Gaia EDR3 photo-astrometric distances (Anders+, 2022)". Vizier Online Data Catalog. Bibcode:2022yCat.1354....0A.
  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. ↑ Pickering, E. C.; Colson, H. R.; Fleming, W. P.; Wells, L. D. (1901). "Sixty-four new variable stars". The Astrophysical Journal. 13: 226. Bibcode:1901ApJ....13..226P. doi:10.1086/140808.
  10. ↑ Skiff, B. A. (October 2014). "Catalogue of Stellar Spectral Classifications". Lowell Observatory. VizieR On-line Data Catalog: B/mk. Bibcode:2014yCat....1.2023S.
  11. ↑ Lançon, A.; Mouhcine, M. (2002). "The modelling of intermediate-age stellar populations. II. Average spectra for upper AGB stars, and their use". Astronomy and Astrophysics. 393: 167. arXiv: astro-ph/0206252 . Bibcode:2002A&A...393..167L. doi:10.1051/0004-6361:20020585. S2CID   15944377.
  12. ↑ Celis s., L. (1977). "Light and colour variations of the Mira stars". Astronomy and Astrophysics Supplement Series. 29: 15. Bibcode:1977A&AS...29...15C.
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.