Gamma1 Caeli

Gamma¹ Caeli, Latinized from γ¹ Caeli, is a double star in the constellation Caelum. It consists of a K-type giant, and a G-type subgiant.

γ¹ Caeli

Location of γ1 Caeli
Observation data Epoch J2000      Equinox J2000
Constellation	Caelum
γ1 Caeli A
Right ascension	05h 04m 24.40s[1]
Declination	−35° 28′ 58.69″[1]
Apparent magnitude (V)	4.57±0.01[2]
γ1 Caeli B
Right ascension	05h 04m 24.19s[3]
Declination	−35° 28′ 56.85″[3]
Apparent magnitude (V)	8.07±0.01[2]
Characteristics
γ1 Caeli A
Spectral type	K2III-IIIb[4]
γ1 Caeli B
Spectral type	G8IV[5]
Astrometry
γ1 Caeli A
Radial velocity (Rv)	9.96±0.19[1] km/s
Proper motion (μ)	RA: 125.430±0.283 mas/yr[1] Dec.: −44.017±0.315 mas/yr[1]
Parallax (π)	17.6430 ± 0.1673 mas[1]
Distance	185 ± 2 ly (56.7 ± 0.5 pc)
γ1 Caeli B
Proper motion (μ)	RA: 123.083±0.075[3] mas/yr Dec.: −45.344±0.100[3] mas/yr
Parallax (π)	17.3832 ± 0.0490 mas[3]
Distance	187.6 ± 0.5 ly (57.5 ± 0.2 pc)
Details
γ1 Caeli A
Mass	1.4+1.1 −0.4[6] M☉
Radius	14.31+0.27 −0.56[1] R☉
Luminosity	69.9±0.8[1] L☉
Temperature	4411+89 −41[1] K
Metallicity [Fe/H]	-0.1[6] dex
Rotational velocity (v sin i)	<1[7] km/s
γ1 Caeli B
Mass	0.91[8] M☉
Surface gravity (log g)	4.45[8] cgs
Temperature	5,702[8] K
Metallicity [Fe/H]	-0.1[8] dex
Other designations
γ1 Cae, HIP 23595, HR 1652, SAO 195532
A: CD−35 2089A, HD 32831A, WDS J05044-3529A
B: CD−35 2089B, HD 32831B, WDS J05044-3529B
Database references
SIMBAD	The system
	A
	B

Properties

Component A

Gamma¹ Caeli A has an apparent magnitude of 4.57, which makes it barely visible to the naked eye. According to parallax, the star is located 185 light years away. Gamma¹ Caeli A has a similar mass to the Sun, but expanded to 14.3 times the Sun's girth. It radiates at 69.9 times the Sun's luminosity from its swollen photosphere at an effective temperature of 4,411 K.

Component B

Gamma¹ Caeli B has an apparent magnitude of 8.07, which makes it visible only in binoculars, and is located at a similar distance to Component A. It has 91% of the Sun's mass, and is metal poor, with 79% the abundance of heavy metals compared to the Sun.

References

1. 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.
2. Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (1 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. 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.
4. Keenan, Philip C.; McNeil, Raymond C. (1 October 1989). "The Perkins catalog of revised MK types for the cooler stars". The Astrophysical Journal Supplement Series. 71: 245–266. Bibcode:1989ApJS...71..245K. doi:10.1086/191373. ISSN 0067-0049. S2CID 123149047.
5. Corbally, C. J. (1 August 1984). "Close visual binaries. I - MK classifications". The Astrophysical Journal Supplement Series. 55: 657–677. Bibcode:1984ApJS...55..657C. doi:10.1086/190973. ISSN 0067-0049.
6. Charbonnel, C.; Lagarde, N.; Jasniewicz, G.; North, P. L.; Shetrone, M.; Krugler Hollek, J.; Smith, V. V.; Smiljanic, R.; Palacios, A.; Ottoni, G. (1 January 2020). "Lithium in red giant stars: Constraining non-standard mixing with large surveys in the Gaia era". Astronomy and Astrophysics. 633: A34. arXiv:1910.12732. Bibcode:2020A&A...633A..34C. doi:10.1051/0004-6361/201936360. ISSN 0004-6361.
7. De Medeiros, J. R.; Alves, S.; Udry, S.; Andersen, J.; Nordström, B.; Mayor, M. (1 January 2014). "A catalog of rotational and radial velocities for evolved stars. V. Southern stars". Astronomy and Astrophysics. 561: A126. arXiv:1312.3474. Bibcode:2014A&A...561A.126D. doi:10.1051/0004-6361/201220762. ISSN 0004-6361.
8. Anders, F.; Khalatyan, A.; Chiappini, C.; Queiroz, A. B.; Santiago, B. X.; Jordi, C.; Girardi, L.; Brown, A. G. A.; Matijevic, 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. (1 August 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. ISSN 0004-6361.