1 Boötis

1 Boötis

Observation data Epoch J2000      Equinox J2000
Constellation	Boötes
Right ascension	13^h 40^m 40.46926^s[1]
Declination	+19° 57′ 20.5839″[1]
Apparent magnitude (V)	5.71[2] (5.78 + 9.60)[3]
Characteristics
Spectral type	A1 V[4] + Am[3]
U−B color index	+0.02[2]
B−V color index	+0.02[2]
Astrometry
Radial velocity (Rv)	−26[5] km/s
Proper motion (μ)	RA: −46.759[1] mas/yr Dec.: +23.302[1] mas/yr
Parallax (π)	10.2412 ± 0.0898 mas[1]
Distance	318 ± 3 ly (97.6 ± 0.9 pc)
Absolute magnitude (MV)	+0.79[6]
Details
1 Boö A
Mass	2.54 ± 0.09[6] M☉
Luminosity	56[6] L☉
Temperature	9,863[6] K
Rotational velocity (v sin i)	60[4] km/s
Age	323[6] Myr
1 Boö B
Mass	1.02[6] M☉
Luminosity	0.76[6] L☉
Temperature	5,370[6] K
Other designations
BD+20°2858, HD 119055, HIP 66727, HR 5144, SAO 82942, CCDM J13407+1958, WDS J13407+1957[7]
Database references
SIMBAD	data

1 Boötis (1 Boo) is a binary star^[3] system in the northern constellation of Boötes, located 318 light years away from the Sun. It is visible to the naked eye as a dim, white-hued star with a combined apparent visual magnitude of 5.71.^[2] The pair had an angular separation of 4.660″ as of 2008. It is moving closer to the Earth with a heliocentric radial velocity of −26 km/s.^[5]

The magnitude 5.78^[3] primary component is an A-type main-sequence star with a stellar classification of A1 V.^[4] This star has 2.5^[6] times the mass of the Sun and is radiating 56^[6] times the Sun's luminosity from its photosphere at an effective temperature of 9,863 K.^[6] It is 323^[6] million years old and is spinning with a projected rotational velocity of 60 km/s.^[4]

The system is a source for X-ray emission, which is most likely coming from the companion star. This magnitude 9.60^[3] component is a possible pre-main sequence star with a mass similar to the Sun. It is radiating 76% of the Sun's luminosity at an effective temperature of 6,370 K.^[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. Lutz, T. E.; Lutz, J. H. (June 1977), "Spectral classification and UBV photometry of bright visual double stars", Astronomical Journal, 82: 431–434, Bibcode:1977AJ.....82..431L, doi:10.1086/112066
3. Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
4. Royer, F.; Zorec, J.; Gómez, A. E. (February 2007), "Rotational velocities of A-type stars. III. Velocity distributions", Astronomy and Astrophysics, 463 (2): 671–682, arXiv:astro-ph/0610785, Bibcode:2007A&A...463..671R, doi:10.1051/0004-6361:20065224, S2CID 18475298
5. Evans, D. S. (June 24, 1966), "The Revision of the General Catalogue of Radial Velocities", in Batten, Alan Henry; Heard, John Frederick (eds.), Determination of Radial Velocities and their Applications, Proceedings from IAU Symposium no. 30 (June 20–24), University of Toronto: International Astronomical Union, Bibcode:1967IAUS...30...57E
6. Hubrig, S.; et al. (June 2001), "Search for low-mass PMS companions around X-ray selected late B stars", Astronomy and Astrophysics, 372: 152–164, arXiv:astro-ph/0103201, Bibcode:2001A&A...372..152H, doi:10.1051/0004-6361:20010452, S2CID 17507782
7. "1 Boo". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-04-01.

External links

• HR 5144
• CCDM J13407+1958
• Image 1 Boötis