Wolf 424
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Virgo |
| Right ascension | 12h 33m 17.38s[1] |
| Declination | +09° 01′ 15.8″[1] |
| Apparent magnitude (V) | A: 13.22 ± 0.01 B: 13.21 ± 0.01[2] |
| Characteristics | |
| Spectral type | dM6e/dM6e[3] |
| U−B color index | 1.19/ |
| B−V color index | 1.84/ |
| Variable type | Flare stars |
| Astrometry | |
| Radial velocity (Rv) | −2[4] km/s |
| Proper motion (μ) | RA: −1730[5] mas/yr Dec.: +203[5] mas/yr |
| Parallax (π) | 227.90 ± 4.60[6] mas |
| Distance | 14.3 ± 0.3 ly (4.39 ± 0.09 pc) |
| Absolute magnitude (MV) | 15.03/15.02[7] |
| Orbit[2] | |
| Primary | GJ 473 A |
| Companion | GJ 473 B |
| Period (P) | 15.532 ± 0.096 yr |
| Semi-major axis (a) | 0.9257 ± 0.0049" (4.062 ± 0.098 AU) |
| Eccentricity (e) | 0.2950 ± 0.0035 |
| Inclination (i) | 103.00 ± 0.15° |
| Longitude of the node (Ω) | 143.48 ± 0.19° |
| Periastron epoch (T) | 1992.297 ± 0.056 |
| Argument of periastron (ω) (secondary) | 347.2 ± 1.5° |
| Details | |
| Mass | A: 0.143 ± 0.011 B: 0.131 ± 0.010[2] M☉ |
| Other designations | |
Wolf 424 is a binary star system comprising two red dwarf stars at a distance of approximately 14.2 light years from the Sun. It is located in the constellation Virgo, between the stars ε Virginis and ο Virginis.
The close binary nature of this star was discovered by Dutch American astronomer Dirk Reuyl in 1941, based upon an elongation of the star found in photographs.[2] The two stars in the Wolf 424 system orbit about each other with a semi-major axis of 4.1 AU and an eccentricity of 0.3. The stars have an orbital period of 15.5 years and have a combined apparent magnitude of about 12.5.
Wolf 424A is a cool main sequence red dwarf star of approximately 0.14 solar masses (147 Jupiters) and a radius of 0.17 solar radii. Its companion, Wolf 424B, is a cool main sequence red dwarf star of approximately 0.13 solar masses (136 Jupiters) and a radius of 0.14 solar radii. They are two of the dimmest known objects within 15 light years of the Sun. In 1967, it was discovered that both are flare stars that undergo random increases in luminosity. The system has been designated FL Virginis, and may experience sunspot activity. The stars may undergo variation in the level of flare activity over periods lasting several years.[3]
Distance
Wolf 424 distance estimates
| Source | Parallax, mas | Distance, pc | Distance, ly | Distance, Pm | Ref. |
|---|---|---|---|---|---|
| Woolley et al. (1970) | 231±5 | 4.33+0.1 −0.09 |
14.12+0.31 −0.3 |
133.6+3 −2.8 |
[8] |
| Gliese & Jahreiß (1991) | 232.2±4.3 | 4.31±0.08 | 14.05+0.27 −0.26 |
132.9+2.5 −2.4 |
[9] |
| van Altena et al. (1995) | 227.9±4.6 | 4.39±0.09 | 14.31+0.29 −0.28 |
135.4+2.8 −2.7 |
[10] |
| RECONS TOP100 (2012) | 227.9±4.6[note 1] | 4.39±0.09 | 14.31+0.29 −0.28 |
135.4+2.8 −2.7 |
[11] |
Non-trigonometric distance estimates are marked in italic. The most precise estimate is marked in bold.
See also
- List of nearest stars
References
- ↑ 1.0 1.1 Cutri, R. M. et al. (March 2003). "2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)". VizieR On-line Data Catalog: II/246. University of Massachusetts and Infrared Processing and Analysis Center, IPAC/California Institute of Technology. Bibcode:2003yCat.2246....0C.
- ↑ 2.0 2.1 2.2 2.3 Torres, Guillermo et al. (January 1999). "The Nearby Low-Mass Visual Binary Wolf 424". The Astronomical Journal 117 (1): 562–573. Bibcode:1999AJ....117..562T. doi:10.1086/300708.
- ↑ 3.0 3.1 Pettersen, B. R. (May 2006). "Flare variability in the close binary FL Vir". Monthly Notices of the Royal Astronomical Society 368 (3): 1392–1394. Bibcode:2006MNRAS.368.1392P. doi:10.1111/j.1365-2966.2006.10210.x.
- ↑ Wilson, Ralph Elmer (1953). General Catalogue of Stellar Radial Velocities. Washington: Carnegie Institution of Washington. Bibcode:1953QB901.W495.....
- ↑ 5.0 5.1 Lépine, Sébastien; Shara, Michael M. (March 2005). "A Catalog of Northern Stars with Annual Proper Motions Larger than 0.15" (LSPM-NORTH Catalog)". The Astronomical Journal 129 (3): 1483–1522. arXiv:astro-ph/0412070. Bibcode:2005AJ....129.1483L. doi:10.1086/427854.
- ↑ van Altena, W. F.; Lee, J. T.; Hoffleit, E. D. (1995). The General Catalogue of Trigonometric [Stellar] Parallaxes (4th ed.). New Haven, CT: Yale University Observatory. Bibcode:1995GCTP..C......0V.
- ↑ Staff (January 1, 2010). "List of the Nearest 100 Stellar Systems". Research Consortium on Nearby Stars. Retrieved 2011-07-01.
- ↑ Woolley R.; Epps E. A.; Penston M. J.; Pocock S. B. (1970). "Woolley 473". Catalogue of stars within 25 parsecs of the Sun. Retrieved 2014-10-22.
- ↑ Gliese, W. and Jahreiß, H. (1991). "Gl 473". Preliminary Version of the Third Catalogue of Nearby Stars. Retrieved 2014-10-22.
- ↑ Van Altena W. F., Lee J. T., Hoffleit E. D. (1995). "GCTP 2890". The General Catalogue of Trigonometric Stellar Parallaxes (Fourth ed.). Retrieved 2014-10-22.
- ↑ "RECONS TOP100". THE ONE HUNDRED NEAREST STAR SYSTEMS brought to you by RECONS (Research Consortium On Nearby Stars). 2012. Retrieved 2014-10-22.
- W. D. Heintz, "Astrometric study of 4 binary stars", 1972, Astronomical Journal, 77, 160.
- Cohen, E. Richard; David R. Lide; George L. Trigg (2003). AIP Physics Desk Reference. Birkhäuser. p. 100. ISBN 0-387-98973-0.
Notes
- ↑ Parallax from van Altena et al. (1995).
External links
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