38 Arietis (abbreviated 38 Ari) is a variable star in the northern constellation of Aries. 38 Arietis is the Flamsteed designation. It was once designated 88 Ceti,[12] forming part of the neighboring constellation of Cetus. With an apparent visual magnitude of +5.18,[3] it is bright enough to be viewed with the naked eye. The measured annual parallax shift of 27.52 mas[2] is equivalent to a distance of approximately 119 light-years (36 parsecs) from Earth.
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Aries |
| Right ascension | 02h 44m 57.57945s[2] |
| Declination | +12° 26′ 44.7297″[2] |
| Apparent magnitude (V) | +5.178[3] |
| Characteristics | |
| Spectral type | A7 III-IV[4] |
| U−B color index | +0.121[3] |
| B−V color index | +0.235[3] |
| Variable type | δ Sct[5] |
| Astrometry | |
| Radial velocity (Rv) | -1.5[6] km/s |
| Proper motion (μ) | RA: +120.49[2] mas/yr Dec.: -85.78[2] mas/yr |
| Parallax (π) | 27.52 ± 0.40 mas[2] |
| Distance | 119 ± 2 ly (36.3 ± 0.5 pc) |
| Absolute magnitude (MV) | 2.22[7] |
| Details | |
| Radius | 2.1[8] R☉ |
| Luminosity | 11[7] L☉ |
| Surface gravity (log g) | 4.04[7] cgs |
| Temperature | 7,638[7] K |
| Rotational velocity (v sin i) | 86[9] km/s |
| Age | 0.58[10] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
The spectrum of this star matches a stellar classification of A7 III-IV,[4] with the luminosity class of III-IV indicating it shows traits part way between the subgiant and giant star stages of its evolution. It is a Delta Scuti variable with a period of 0.0355 days (51 minutes) and a magnitude change of 0.040.[5] This star is larger than the Sun, with more than double the Sun's radius and 11 times the luminosity.[7] This energy is being radiated into outer space from the atmosphere at an effective temperature of 7,638 K,[7] giving it the white-hued glow of an A-type star.
References
edit- ^ Valtier, J. C.; Sareyan, J. P.; Le Contel, J. M.; Zribi, G. (January 1974). "Photometric observations of delta Scuti stars. II. HR 432, HR 515, HR 812". Astronomy & Astrophysics Supplement Series. 18: 235–249. Retrieved 28 October 2021.
- ^ a b c d e f 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, S2CID 18759600.
- ^ a b c d Gutierrez-Moreno, Adelina; et al. (1966), "A System of photometric standards", Publications of the Department of Astronomy University of Chile, 1, Publicaciones Universidad de Chile, Department de Astronomy: 1–17, Bibcode:1966PDAUC...1....1G.
- ^ a b Cowley, A.; et al. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal, 74: 375–406, Bibcode:1969AJ.....74..375C, doi:10.1086/110819.
- ^ a b Rodríguez, E.; López-González, M. J.; López de Coca, P. (June 2000), "A revised catalogue of delta Sct stars", Astronomy and Astrophysics Supplement Series, 144 (3): 469–474, Bibcode:2000A&AS..144..469R, doi:10.1051/aas:2000221, hdl:10261/226673.
- ^ Wilson, R. E. (1953), "General Catalogue of Stellar Radial Velocities", Carnegie Institute Washington D.C. Publication, Carnegie Institute of Washington D.C., Bibcode:1953GCRV..C......0W.
- ^ a b c d e f Paunzen, E.; et al. (September 2002), "On the Period-Luminosity-Colour-Metallicity relation and the pulsational characteristics of lambda Bootis type stars", Astronomy and Astrophysics, 392 (2): 515–528, arXiv:astro-ph/0207494, Bibcode:2002A&A...392..515P, doi:10.1051/0004-6361:20020854, S2CID 54666586.
- ^ Pasinetti Fracassini, L. E.; Pastori, L.; Covino, S.; Pozzi, A. (February 2001). "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics". Astronomy and Astrophysics. 367 (2): 521–524. arXiv:astro-ph/0012289. Bibcode:2001A&A...367..521P. doi:10.1051/0004-6361:20000451. S2CID 425754.
- ^ Royer, F.; et al. (October 2002), "Rotational velocities of A-type stars in the northern hemisphere. II. Measurement of v sin i", Astronomy and Astrophysics, 393: 897–911, arXiv:astro-ph/0205255, Bibcode:2002A&A...393..897R, doi:10.1051/0004-6361:20020943, S2CID 14070763.
- ^ Vican, Laura (June 2012), "Age Determination for 346 Nearby Stars in the Herschel DEBRIS Survey", The Astronomical Journal, 143 (6): 135, arXiv:1203.1966, Bibcode:2012AJ....143..135V, doi:10.1088/0004-6256/143/6/135, S2CID 118539505.
- ^ "38 Ari". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2012-07-18.
- ^ Wagman, M. (August 1987), "Flamsteed's Missing Stars", Journal for the History of Astronomy, 18 (3): 215, Bibcode:1987JHA....18..209W, doi:10.1177/002182868701800305, S2CID 118445625.