catalogues and names

The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version)

SKY2000 - Master Star Catalog

Smithsonian Astrophysical Observatory Star Catalog

The Washington Visual Double Star Catalog, 1996.0

Combined General Catalogue of Variable Stars (Vol. I-III)

catalogues and names

catalogues and names	q2Tau, tet 2 Tau, 78 Tau, HR 1412, HD 28319, SAO 93957, BD +15 632, 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 (2000.73)	RA: 4h 28min 43sec	DEC: +15° 52' 21''
position (B1900)	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
galactic coordinates	longitude: 180.35°	latitude: -22.01°

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

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
position (2000.73)	RA: 4h 28min 42sec	DEC: +15° 52' 21''	JD: 2451810.88
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 arcsec		±0.003 arcsec	source: 25
galactic coord. (B1950)	longitude: 180.35°	latitude: -22.01°

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:

source of data: 30

variability type	10
var. amplitude	0.07
var. period	0.08

double/multiple star system information:

source of data: 19

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 (B1950)	RA: 4h 25min 48.22sec	DEC: +15° 45' 41.8''	±0.014 arcsec
position (2000.73)	RA: 4h 28min 42sec	DEC: +15° 52' 22''	JD: 2451810.88
position (J2000)	RA: 4h 28min 39.715sec	DEC: +15° 52' 15.23''
proper motion B1950 (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 (equinox 1950.0)

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.