RV Caeli

RV Caeli

Location of RV Caeli (circled)
Observation data Epoch J2000      Equinox J2000
Constellation	Caelum
Right ascension	04^h 28^m 09.46368^s[1]
Declination	−41° 51′ 35.4013″[1]
Apparent magnitude (V)	6.4±0.01[2]
Characteristics
Evolutionary stage	AGB[3]
Spectral type	M1 III[4]
B−V color index	+1.64[5]
Variable type	semiregular[6]
Astrometry
Radial velocity (Rv)	97.9±0.5[7] km/s
Proper motion (μ)	RA: −14.75 mas/yr[8] Dec.: +2.87 mas/yr[8]
Parallax (π)	2.4402 ± 0.0229 mas[1]
Distance	1,340 ± 10 ly (410 ± 4 pc)
Absolute magnitude (MV)	−1.36[9]
Details
Mass	1.14[10] M☉
Radius	107[11] R☉
Luminosity	976±30[12] L☉
Surface gravity (log g)	0.67[10] cgs
Temperature	3,843±122[13] K
Metallicity [Fe/H]	−0.15[10] dex
Other designations
4 G. Caeli[14], CD−42°1510, CPD−42°469, GC 5451, HD 28552, HIP 20856, HR 1429, SAO 216821[15]
Database references
SIMBAD	data

RV Caeli, also known as HD 28552, is a solitary, red hued variable star located in the southern constellation Caelum, the chisel. It has an apparent magnitude of 6.4,^[2] placing it near the limit for naked eye visibility. The object is located at a distance of 1,340 light years based on parallax measurements from Gaia DR3,^[1] but is rapidly receding with a heliocentric radial velocity of 98 km/s.^[7]

A visual band light curve for RV Caeli, adapted from Tabur et al. (2009).^[16]

Hipparcos has found it to vary between its photometric values of 6.44 and 6.56,^[6] which roughly corresponds with the magnitude as seen with the naked eye. It was first suspected of variability in 1970,^[17] and a 1982 survey also identified suspected variations. However, it could not confirm it was a variable star.^[18] It was confirmed as a variable star in 1999 on the basis of the Hipparcos photometry and given the variable star designation RV Caeli.^[19]

RV Caeli is an evolved red giant star with a stellar classification of M1 III.^[4] It is currently on the asymptotic giant branch,^[3] generating energy via hydrogen and helium shell fusion around an inert carbon core. It has 114% the mass of the Sun^[10] but has expanded to over 100 times its girth.^[11] It radiates 976 times the luminosity of the Sun^[12] from its photosphere at an effective temperature of 3,843 K.^[13] RV Caeli is metal deficient, having an iron abundance 70% that of the Sun.

References

1. 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.
2. Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (March 2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27 – L30. Bibcode:2000A&A...355L..27H. ISSN 0004-6361.
3. Eggen, Olin J. (July 1992). "Asymptotic giant branch stars near the sun". The Astronomical Journal. 104: 275. Bibcode:1992AJ....104..275E. doi:10.1086/116239. ISSN 0004-6256.
4. Houk, Nancy (1978). Michigan catalogue of two-dimensional spectral types for the HD stars Volume II: Declinations −52° to −41°. Bibcode:1978mcts.book.....H.
5. Johnson, H. L.; Mitchell, R. I.; Iriarte, B.; Wisniewski, W. Z. (1966). "UBVRIJKL Photometry of the Bright Stars". Communications of the Lunar and Planetary Laboratory. 4: 99–110. Bibcode:1966CoLPL...4...99J.
6. VSX (25 August 2009). "RV Cae". International Variable Star Index. American Association of Variable Star Observers. Retrieved 30 June 2014.
7. Gontcharov, G. A. (November 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. eISSN 1562-6873. ISSN 1063-7737. S2CID 119231169.
8. van Leeuwen, Floor (13 August 2007). "Validation of the new Hipparcos reduction". Astronomy & Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. eISSN 1432-0746. ISSN 0004-6361. Hipparcos record for this source at VizieR.
9. Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331–346. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. eISSN 1562-6873. ISSN 1063-7737. S2CID 119257644.
10. Anders, F.; et al. (August 2019). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18". Astronomy & Astrophysics. 628: A94. arXiv:1904.11302. Bibcode:2019A&A...628A..94A. doi:10.1051/0004-6361/201935765. eISSN 1432-0746. ISSN 0004-6361.
11. Kervella, Pierre; Arenou, Frédéric; Thévenin, Frédéric (2022). "Stellar and substellar companions from Gaia EDR3". Astronomy & Astrophysics. 657: A7. arXiv:2109.10912. Bibcode:2022A&A...657A...7K. doi:10.1051/0004-6361/202142146. eISSN 1432-0746. ISSN 0004-6361.
12. 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.
13. Stassun, Keivan G.; et al. (9 September 2019). "The Revised TESS Input Catalog and Candidate Target List". The Astronomical Journal. 158 (4): 138. arXiv:1905.10694. Bibcode:2019AJ....158..138S. doi:10.3847/1538-3881/ab3467. eISSN 1538-3881.
14. Gould, Benjamin Apthorp (1878). "Uranometria Argentina : brillantez y posicion de las estrellas fijas, hasta la septima magnitud, comprendidas dentro de cien grados del polo austral : con atlas". Resultados del Observatorio Nacional Argentino. 1. Bibcode:1879RNAO....1.....G.
15. "HD 28552". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved September 28, 2022.
16. Tabur, V.; Bedding, T. R.; Kiss, L. L.; Moon, T. T.; Szeidl, B.; Kjeldsen, H. (December 2009). "Long-term photometry and periods for 261 nearby pulsating M giants". Monthly Notices of the Royal Astronomical Society. 400 (4): 1945–1961. arXiv:0908.3228. Bibcode:2009MNRAS.400.1945T. doi:10.1111/j.1365-2966.2009.15588.x. S2CID 15358380.
17. Eggen, O. J.; Stokes, N. R. (July 1970). "Narrow-Band and Broad-Band Photometry of Red Stars. III. Southern Giants". The Astrophysical Journal. 161: 199. Bibcode:1970ApJ...161..199E. doi:10.1086/150525. eISSN 1538-4357. ISSN 0004-637X.
18. Rufener, F.; Bartholdi, P. (June 1982). "List of 333 variable, microvariable or suspected variable stars detected in the Geneva photometry". Astronomy and Astrophysics Supplement Series. 48: 503. Bibcode:1982A&AS...48..503R.
19. Kazarovets, E. V.; Samus, N. N.; Durlevich, O. V.; Frolov, M. S.; Antipin, S. V.; Kireeva, N. N.; Pastukhova, E. N. (January 1999). "The 74th Special Name-list of Variable Stars". Information Bulletin on Variable Stars. 4659: 1. Bibcode:1999IBVS.4659....1K. ISSN 0374-0676.