39 Arietis
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Aries |
| Right ascension | 02h 47m 54.54142s[1] |
| Declination | +29° 14′ 49.6132″[1] |
| Apparent magnitude (V) | 4.514[2] |
| Characteristics | |
| Spectral type | K1.5 III[3] |
| U−B color index | +1.083[2] |
| B−V color index | +1.118[2] |
| R−I color index | 0.58 |
| Astrometry | |
| Radial velocity (Rv) | –15.53 ± 0.14[4] km/s |
| Proper motion (μ) | RA: +149.47 ± 0.25[1] mas/yr Dec.: –127.05 ± 0.18[1] mas/yr |
| Parallax (π) | 19.01 ± 0.21[1] mas |
| Distance | 172 ± 2 ly (52.6 ± 0.6 pc) |
| Details | |
| Mass | 1.6[5] M☉ |
| Radius | 11.1 ± 0.8[3] R☉ |
| Luminosity | 56[4] L☉ |
| Surface gravity (log g) | 2.7[4] cgs |
| Temperature | 4,603[4] K |
| Metallicity [Fe/H] | –0.02[4] dex |
| Rotational velocity (v sin i) | 4.5[4] km/s |
| Other designations | |
39 Arietis (abbreviated 39 Ari) is a star in the northern constellation of Aries. 39 Arietis is the Flamsteed designation. It is visible to the naked eye with an apparent visual magnitude of +4.5.[2] The distance to this star, as determined from an annual parallax shift of 19.01 mas,[1] is approximately 172 light-years (53 parsecs).
This is a giant star with a stellar classification of K1.5 III.[3] It is currently at an evolutionary stage known as a red clump, indicating that it is generating energy through the fusion of helium at its core.[5] 39 Arietis has 1.6[5] times the mass of the Sun, but its outer envelope has expanded to around 11[3] times the Sun's radius. It shines with 56 times the luminosity of the Sun.[4] This energy is being radiated into outer space from its outer atmosphere at an effective temperature of 4,603 K,[4] giving it the cool orange-hued glow of a K-type star.[7]
References
- 1 2 3 4 5 6 van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752
, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357. - 1 2 3 4 Oja, T., "UBV photometry of stars whose positions are accurately known. III", Astronomy and Astrophysics Supplement Series, 65 (2): 405–4.
- 1 2 3 4 Nordgren, Tyler E.; et al. (December 1999), "Stellar Angular Diameters of Late-Type Giants and Supergiants Measured with the Navy Prototype Optical Interferometer", The Astronomical Journal, 118 (6): 3032–3038, Bibcode:1999AJ....118.3032N, doi:10.1086/301114
- 1 2 3 4 5 6 7 8 Massarotti, Alessandro; et al. (January 2008), "Rotational and Radial Velocities for a Sample of 761 HIPPARCOS Giants and the Role of Binarity", The Astronomical Journal, 135 (1): 209–231, Bibcode:2008AJ....135..209M, doi:10.1088/0004-6256/135/1/209.
- 1 2 3 Tautvaišienė, G.; et al. (December 2010), "C, N and O abundances in red clump stars of the Milky Way", Monthly Notices of the Royal Astronomical Society, 409 (3): 1213–1219, arXiv:1007.4064, Bibcode:2010MNRAS.409.1213T, doi:10.1111/j.1365-2966.2010.17381.x.
- ↑ "NLTT 8982 -- High proper-motion Star", SIMBAD Astronomical Database, Centre de Données astronomiques de Strasbourg, retrieved 2012-07-18.
- ↑ "The Colour of Stars", Australia Telescope, Outreach and Education, Commonwealth Scientific and Industrial Research Organisation, December 21, 2004, retrieved 2012-01-16