R Boötis is a variable star in the northern constellation of Boötes. Typically the star is too faint to be readily visible to the naked eye, with a brightness that fluctuates between apparent visual magnitudes of 9.98.[5] The distance to this star is approximately 2,150 light years based on parallax measurements.[2] It is drifting closer with a radial velocity of about −58 km/s.[7]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Boötes |
| Right ascension | 14h 37m 11.57616s[2] |
| Declination | 26° 44′ 11.6562″[2] |
| Apparent magnitude (V) | 6.0 - 13.3[3] |
| Characteristics | |
| Spectral type | M4-8e[4] |
| B−V color index | 1.50±0.51[5] |
| Variable type | Mira variable[3][6] |
| Astrometry | |
| Radial velocity (Rv) | −58.0±4.7[7] km/s |
| Proper motion (μ) | RA: –25.537[2] mas/yr Dec.: 11.968[2] mas/yr |
| Parallax (π) | 1.5204 ± 0.0586 mas[2] |
| Distance | 2,150 ± 80 ly (660 ± 30 pc) |
| Details | |
| Mass | 0.86[8] M☉ |
| Radius | 245[9] R☉ |
| Luminosity | 5,900[10] L☉ |
| Surface gravity (log g) | −0.44[8] cgs |
| Temperature | 2,640[8] K |
| Metallicity [Fe/H] | 0.55[8] dex |
| Other designations | |
| Database references | |
| SIMBAD | data |
The variability of this star was discovered by German astronomer F. W. Argelander in 1857.[12] It is classified as a Mira-type pulsating variable that ranges in brightness from magnitude 6.0 down to 13.3 with a period of 223.11 days.[3][6] The stellar classification of the star ranges from M4e to M8e,[4] where the 'e' indicates emission features in the spectrum.
The angular diameter of R Boötis has been measured at 3.45±0.1 mas,[13] which at its estimated distance of 660 parsecs[2] gives a physical size 245 times solar.[9]
References
edit- ^ "Download Data". aavso.org. AAVSO. Retrieved 1 October 2021.
- ^ a b c d e f g Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
- ^ a b c Samus, N. N.; et al. (2017). "General Catalogue of Variable Stars". Astronomy Reports. 5.1. 61 (1): 80–88. Bibcode:2017ARep...61...80S. doi:10.1134/S1063772917010085. S2CID 125853869.
- ^ a b Keenan, Philip C.; et al. (1974). "Revised Catalog of Spectra of Mira Variables of Types ME and Se". Astrophysical Journal Supplement. 28: 271. Bibcode:1974ApJS...28..271K. doi:10.1086/190318.
- ^ a b 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. S2CID 119257644.
- ^ a b VSX (4 January 2010). "R Boötis". AAVSO Website. American Association of Variable Star Observers. Retrieved 26 June 2014.
- ^ a b Gontcharov, G. A. (November 2006). "Pulkovo Compilation of Radial Velocities for 35495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. S2CID 119231169.
- ^ a b c d 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. (2019-08-01). "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. S2CID 131780028.
- ^ a b Lang, Kenneth R. (2006), Astrophysical formulae, Astronomy and astrophysics library, vol. 1 (3 ed.), Birkhäuser, ISBN 3-540-29692-1. The radius (R*) is given by:
- ^ Gaia Collaboration; Brown, A. G. A.; Vallenari, A.; Prusti, T.; de Bruijne, J. H. J.; Babusiaux, C.; Bailer-Jones, C. A. L.; Biermann, M.; Evans, D. W.; Eyer, L.; Jansen, F. (2018-08-01). "Gaia Data Release 2. Summary of the contents and survey properties". Astronomy and Astrophysics. 616: A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. ISSN 0004-6361.
- ^ "R Boo". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2021-05-01.
- ^ Isles, J. E.; Saw, D. R. B. (February 1987). "106 Mira Stars, - I. R Ari, R Aur, X Aur, R Boo and S Boo". Journal of the British Astronomical Association. 97 (2): 106–116. Bibcode:1987JBAA...97..106I.
- ^ Richichi, A.; Percheron, I.; Khristoforova, M. (2005-02-01). "CHARM2: An updated Catalog of High Angular Resolution Measurements". Astronomy and Astrophysics. 431: 773–777. doi:10.1051/0004-6361:20042039. ISSN 0004-6361. R Boötis' database entry at VizieR.
