Pi¹ Columbae

Pi¹ Columbae, Latinized from π¹ Columbae, is a star in the southern constellation of Columba. With an apparent visual magnitude of 6.13,[2] it is a dim, white-hued star that is near the limit of visibility for the naked eye. It is located approximately 280 light years from the Sun based on parallax,[1] and has an absolute magnitude of +1.55.[5]

Pi¹ Columbae

Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Columba
Right ascension	06^h 06^m 41.03304^s[1]
Declination	−42° 17′ 55.5846″[1]
Apparent magnitude (V)	6.13[2]
Characteristics
Spectral type	A2mA5-A9[3]
U−B color index	+0.11[2]
B−V color index	+0.25[2]
Astrometry
Radial velocity (Rv)	2.0±4.3[4] km/s
Proper motion (μ)	RA: −26.957[1] mas/yr Dec.: −5.880[1] mas/yr
Parallax (π)	11.6365 ± 0.1653[1] mas
Distance	280 ± 4 ly (86 ± 1 pc)
Absolute magnitude (MV)	+1.55[5]
Details
Radius	2.49+0.15 −0.11[1] R☉
Luminosity	20.237+0.23 −0.33[1] L☉
Temperature	7,765+171 −228[1] K
Rotational velocity (v sin i)	70[6] km/s
Other designations
π^1 Col, CPD−42°2343, GC 7785, HD 42078, HIP 28957, HR 2171, SAO 217720[7]
Database references
SIMBAD	data

This is an Am star with a stellar classification of A2mA5-A9.[3] It has 2.5 times the Sun's radius and shines with 20 times the luminosity of the Sun at an effective temperature of 7,765 K.[1] The star is spinning with a projected rotational velocity of 70 km/s.[6]

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. Feinstein, A. (1974), "Photoelectric UBVRI observations of AM stars", Astronomical Journal, 79: 1290, Bibcode:1974AJ.....79.1290F, doi:10.1086/111675.
3. Houk, Nancy (1978), Michigan catalogue of two-dimensional spectral types for the HD stars, 2, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode:1978mcts.book.....H.
4. de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics, 546: 14, arXiv:1208.3048, Bibcode:2012A&A...546A..61D, doi:10.1051/0004-6361/201219219, A61.
5. 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.
6. Levato, O. H. (August 1972), "Rotational Velocities and Spectral Types of Some A-Type Stars", Publications of the Astronomical Society of the Pacific, 84 (500): 584, Bibcode:1972PASP...84..584L, doi:10.1086/129336
7. "pi01 Col". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-10-14.