q2Tauri
| catalogues and names | q2Tau, tet 2 Tau, 78 Tau, HR 1412, HD 28319, SAO 93957, WDS 04287+1552A |
| constellation | Taurus |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
position, motion, parallax:
| position (J2000) | RA: 4h 28min 39,7sec | DEC: +15° 52' 15'' |
| position (J1900) | RA: 4h 22min 57sec | DEC: +15° 38' 57'' |
| proper motion (J2000) | RA: 0,103 arcsec/a | DEC: -0,025 arcsec/a |
| radial velocity | 40 km/s note: spectroscopic binaries, single lined spectra note: orbital data avaible |
|
| rotational velocity | 78 km/s (uncertain) (variable) | |
| trigonometric parallax | 0,029 arcsec | |
magnitude
| visual magnitude | 3,4 (V on UBV Johnson system) |
spectral / color information
| spectral class | A7III |
| B-V-magnitude | 0,18 |
| U-B-magnitude | 0,13 |
| R-I-magnitude | 0,09 |
variability information
| variable star identification | The2 Tau |
| note (category: variability): | Delta Sct, amp. 0.03V (variable), 0.080d. Possibly also eclipsing. |
double/multiple star system information
| number of components of multiple star system | 4 |
| separation | 337,4 arcsec |
| mag difference (of double or brightest multiple) | 0,4 |
| component ID | AB |
| note | Worley (1978) update of the IDS |
| note (category: double and multiple data): | CPM with HR 1411. Close occultation binary, 3.5, 5.8v, sep. 0.005". |
| note (category: spectroscopic binaries): | Sep. 0.005", 140.728d, K 31.0k/s, V0 +39.6k/s, asini 39.7, e 0.75. |
miscellaneous information
| note (category: group membership): | Member of Hyades cluster; Mel 25 #72. |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
| position (J2000) | RA: 4h 28min 39,716sec | DEC: +15° 52' 15,26'' | ±0,43 arcsec | source: 16 |
| proper motion (J2000) | RA: 0,0067 arcsec/a | DEC: -0,028 arcsec/a | source: 25 | |
| radial velocity | 40 km/s | source: 25 | ||
| trigonometric parallax | 0,029 | ±0,003 arcsec | source: 25 | |
| galactic coord. (B1950) | longitude: 180,35° | latitude: -22,01° | ||
| GCI unit vector (J2000) | X: 0,373278 | Y: 0,886497 | Z: 0,273471 | |
magnitude:
| visual | 3,4 (observed) | source: 31 |
| photovisual | 3,6 | source: 2 |
| photographic | 3,6 | source: 16 |
spectral information:
| spectral class | F0 | source: 96 | |
| Morgan-Keenan | A7III | source: 25 | |
| B-magnitude | 3,58 ±0,05 | B-V-magnitude | 0,18 |
| U-magnitude | 3,71 ±0,05 | U-B-magnitude | 0,13 |
variability information:
| variability type | 10 |
| var. amplitude | 0,07 |
| var. period | 0,08 |
double/multiple star system information:
| separation between brightest and second brightest component | 337,4 arcsec |
| position angle | 346 ° |
| component | magnitude | spectral class | catalogue(s)/name(s) |
| A | 3,4 | F0 | q2Tauri, 78 Tau, HR 1412, HD 28319, SAO 93957 |
| B | 3,84 | K0 | q1Tauri, 77 Tau, HR 1411, HD 28307, SAO 93955 |
sources:
| 2 | HD and HDE Catalogs |
| Cannon, A.J., and E.C. Pickering, Harvard Annals, Vols 91-99, 1918-24, Cambridge, Massachusetts: Harvard University; Cannon, A.J., Harvard Annals, Vol. 100, 1925-36, Cambridge, Massachusetts: Harvard University; and Cannon, A.J., and M. Walton Mayall, Harvard Annals, Vol. 112, 1949, Cambridge, Massachusetts: Harvard University | |
| 16 | PPM North and PPM South Catalogs and PPM Supplement |
| Roser, S., and U. Bastian, "Catalogue of Positions and Proper Motions," A&AS, Vol. 74, p. 449, 1988, and Bastian, U., et al., "Catalogue of Positions and Proper Motions - South," 1993 | |
| 19 | WDS Catalog |
| Worley, C.E., and G.G. Douglass, Washington Catalog of Visual Double Stars 1996.0, United States Naval Observatory, 1996 | |
| 25 | Bright Star Catalogue, 5th edition |
| Hoffleit, D. and Warren, W.H. Jr., The Bright Star Catalogue, 5th Revised Edition, Version 2, 1994 | |
| 30 | GCVS, 4th edition |
| Kholopov, P.N., et al., General Catalogue of Variable Stars, fourth edition, Moscow: Nauka Publishing House, 1985-88 | |
| 31 | CRM' (non-GCVS variable data) |
| Warren, W.H. Jr., Northern Hemisphere Catalog of Red Magnitudes, 1994 | |
| 96 | SAO or HD/HDE Catalog |
| Reference from Value 1 or Reference from Value 2 | |
data from Smithsonian Astrophysical Observatory Star Catalog (SAO Staff 1966; USNO, ADC 1990)
position and proper motion:
| position (J1950) | RA: 4h 25min 48,22sec | DEC: +15° 45' 41,8'' | ±0,014 arcsec |
| position (J2000) | RA: 4h 28min 39,715sec | DEC: +15° 52' 15,23'' | |
| proper motion J1950 (FK4) | RA: 0,0071 arcsec/a | DEC: -0,024 arcsec/a | ±0,002 arcsec/a in RA ±0,002 arcsec/a in DEC |
| proper motion J2000 (FK5) | RA: 0,0071 arcsec/a | DEC: -0,025 arcsec/a | |
| source of proper motion data | Determined by source catalog | ||
magnitude:
| visual | 3,6 (accuracy: 2 decimals) |
| source of visual magnitude data | Taken from Harvard or San Luis photometry. |
spectral information:
| spectral class | F0 |
| source of spectral data | Taken from the Henry Draper Catalogue or no spectrum in source catalog. |
catalogues
| source catalogue | GC, catalogue number: 5436 |
| Durchmusterung | BD+15 632 |
| Boss General Catalogue | 5436 |
| Henry Draper Catalogue | 28319 |
data from The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996)
position and proper motion:
| position (J2000) | RA: 4h 28,7min | DEC: +15° 52' |
| proper motion (J2000) | RA: 0,108 arcsec/a | DEC: -0,025 arcsec/a |
double/multiple star system information:
| component | year | number of measures | position angle | angular separation | magnitude of 1st component | magnitude of 2nd component | spectral class(es) | discoverer code |
| - | 1836 | 8 | 346° | 337,4'' | 3,4 | - | A7III | STF 10 |
discoverer information:
| discoverer code | discoverer | reference |
| STF 10 | Struve, F.G.W. | - |
notes:
| note | Theta (2) Tau. B is BD+15@631. Proper motion of B +082 -026. A spectroscopic and occultation binary. Also, variable, probably of Delta Scuti type. |
data from Combined General Catalogue of Variable Stars (Vol. I-III) (Kholopov+ 1998)
position:
| position (J1950) | RA: 4h 25min 48,2sec | DEC: +15° 45' 42'' |
variability informations:
| variability type | DSCTC+E: | pulsating variable star close binary eclipsing system |
| magnitute at max. brightness | 3,35 | |
| magnitute at min. brightness | 3,42 | |
| photometric system | visual, photovisual or Johnson's V | |
| period [d] | 0,07564 | |
| duration of the eclipse | 50 % of period |
spectral information
| spectral class | A7III |
references
| to a study | Vol. III GCVS |
| to a chart/photograph | no chart is avaible, but the star is contained in the 'Bonner Durchmusterung' |
miscanellous
| ID in the GCVS catalogue | 78/90082 |
| constellation | Taurus |
| notes on existence | The star is equivalent to '0789011 lam'. |
| There are notes in published catalog. | |
variability type description
| variability type | description |
| DSCTC | Variables of the Delta Scuti type. These are pulsating variables of spectral types A0-F5 III-V displaying light amplitudes from 0.003 to 0.9 mag in V (usually several hundredths of a magnitude) and periods from 0.01 to 0.2 days. The shapes of the light curves, periods, and amplitudes usually vary greatly. Radial as well as nonradial pulsations are observed. The variability of some members of this type appears sporadically and sometimes completely ceases, this being a consequence of strong amplitude modulation with the lower value of the amplitude not exceeding 0.001 mag in some cases. The maximum of the surface layer expansion does not lag behind the maximum light for more than 0.1 periods. DSCT stars are representatives of the galactic disk (flat component) and are phenomenologically close to the SX Phe variables. DSCTC Low amplitude group of Delta Sct variables (light amplitude <0.1 mag in V). The majority of this type's representatives are stars of luminosity class V; objects of this subtype generally are representative of the Delta Sct variables in open clusters. |
| E | Eclipsing binary systems. These are binary systems with orbital planes so close to the observer's line of sight (the inclination i of the orbital plane to the plane orthogonal to the line of sight is close to 90 deg) that the components periodically eclipse each other. Consequently, the observer finds changes of the apparent combined brightness of the system with the period coincident with that of the components' orbital motion. EA Algol (Beta Persei)-type eclipsing systems. Binaries with spherical or slightly ellipsoidal components. It is possible to specify, for their light curves, the moments of the beginning and end of the eclipses. Between eclipses the light remains almost constant or varies insignificantly because of reflection effects, slight ellipsoidality of components, or physical variations. Secondary minima may be absent. An extremely wide range of periods is observed, from 0.2 to >= 10000 days. Light amplitudes are also quite different and may reach several magnitudes. EB Beta Lyrae-type eclipsing systems. These are eclipsing systems having ellipsoidal components and light curves for which it is impossible to specify the exact times of onset and end of eclipses because of a continuous change of a system's apparent combined brightness between eclipses; secondary minimum is observed in all cases, its depth usually being considerably smaller than that of the primary minimum; periods are mainly longer than 1 day. The components generally belong to early spectral types (B-A). Light amplitudes are usually <2 mag in V. EW W Ursae Majoris-type eclipsing variables. These are eclipsers with periods shorter than 1 days, consisting of ellipsoidal components almost in contact and having light curves for which it is impossible to specify the exact times of onset and end of eclipses. The depths of the primary and secondary minima are almost equal or differ insignificantly. Light amplitudes are usually <0.8 mag in V. The components generally belong to spectral types F-G and later. |