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	Aliioth, e UMa, eps UMa, 77 UMa, HR 4905, HD 112185, SAO 28553, BD +56 1627, FK5: 483, WDS 12540+5558
other names	Alioth, Aliath
constellation	Ursa Major

data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)

note (category: star names):

ALIOTH; Aliath.

position, motion, parallax:

position (J2000)	RA: 12h 54min 1.7sec	DEC: +55° 57' 35''
position (2000.72)	RA: 12h 54min 4sec	DEC: +55° 57' 21''
position (B1900)	RA: 12h 49min 37.8sec	DEC: +56° 30' 9''
proper motion (J2000)	RA: 0.112 arcsec/a	DEC: -0.006 arcsec/a
radial velocity	-9 km/s note: spectroscopic binaries
rotational velocity	38 km/s (uncertain) (variable)
trigonometric parallax	0.009 arcsec
galactic coordinates	longitude: 122.18°	latitude: 61.16°

magnitude

visual magnitude

1.77 (V on UBV Johnson system)

spectral / color information

spectral class	A0pCr
B-V-magnitude	-0.02
U-B-magnitude	0.02
R-I-magnitude
IR-note	object is infrared source (NASA merged infrared catalogue, Schmitz et al., 1978)

note (category: spectra):

Also classified A0pCrMn.

variability information

variable star identification

Eps UMa

note (category: variability):

Alpha CV 1.76 - 1.79V, 5.0887d. Spectrum variable. Photometric var. due to UV absorption from overabundant metals.

double/multiple star system information

note (category: spectroscopic binaries):

0.95d and 4.15y. SB unresolved by speckle interferometry 1980.47. Binary nature questioned. Rotational period 5.09d.

miscellaneous information

note (category: group membership):

"Dipper Stars;" Sirius group; UMa stream; UMa moving cluster.

note (category: stellar radii or diameters):

4 solar radii.

data from SKY2000 - Master Star Catalog (Myers+ 1997)

position, motion, parallax:

position (J2000)	RA: 12h 54min 1.748sec	DEC: +55° 57' 35.47''	±0.06 arcsec	source: 15
position (2000.72)	RA: 12h 54min 4sec	DEC: +55° 57' 21''	JD: 2451809.24
proper motion (J2000)	RA: 0.0133 arcsec/a	DEC: -0.006 arcsec/a		source: 25
radial velocity	-9 km/s			source: 25
trigonometric parallax	0.009 arcsec		±0.001 arcsec	source: 25
galactic coord. (B1950)	longitude: 122.18°	latitude: 61.16°

magnitude:

visual	1.77 (observed)	source: 25
photovisual	1.7	source: 2

spectral information:

spectral class	A0		source: 96
Morgan-Keenan	A0pCr		source: 25
B-magnitude	1.75 ±0.05	B-V-magnitude	-0.02
U-magnitude	1.77 ±0.05	U-B-magnitude	0.02

variability information:

source of data: 30

variability type	160
var. amplitude	0.02
var. period	5.09
var. epoch	2426437 5. April 1931, 12:00:00 UT
next max light	2451810.65 23. September 2000, 03:36:00 UT

double/multiple star system information:

source of data: 19

separation between brightest and second brightest component	0.1 arcsec
position angle	94 °

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
15	FK5, FK5 Extension and FK5 Supplement
Fricke, W., H. Schwan and T. Lederle, "Fifth Fundamental Catalogue (FK5), Part I. The Basic Fundamental Stars," Veroff. Astronomisches Recheninstitut, No. 32, Heidelberg, Germany, 1988, and Fricke, W., H. Schwan, and T.E. Corbin, "Fifth Fundamental Catalogue (FK5), Part II. The FK5 Extension," Veröff. Astronomisches Recheninstitut, No. 33, Heidelberg, Germany, 1991
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
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: 12h 51min 50.084sec	DEC: +56° 13' 51.14''	±0.004 arcsec
position (2000.72)	RA: 12h 54min 3sec	DEC: +55° 57' 21''	JD: 2451809.24
position (J2000)	RA: 12h 54min 1.757sec	DEC: +55° 57' 35.55''
proper motion B1950 (FK4)	RA: 0.0131 arcsec/a	DEC: -0.01 arcsec/a	±0.001 arcsec/a in RA ±0.001 arcsec/a in DEC
proper motion J2000 (FK5)	RA: 0.0134 arcsec/a	DEC: -0.005 arcsec/a
source of proper motion data	Determined by source catalog

magnitude:

visual	1.7 (accuracy: 2 decimals)
source of visual magnitude data	Taken from the "Henry Draper Catalogue".

spectral information:

spectral class	A0p
source of spectral data	Taken from the Henry Draper Catalogue or no spectrum in source catalog.

catalogues

source catalogue	FK4, catalogue number: 483
Durchmusterung	BD+56 1627
Boss General Catalogue	17518
Henry Draper Catalogue	112185

data from The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996)

position and proper motion:

position (J2000)	RA: 12h 54min	DEC: +55° 58'
proper motion (J2000)	RA: 0.112 arcsec/a	DEC: -0.006 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
-	1975	1	94°	0.1''	1.77	-	A0p	BLM

discoverer information:

discoverer code	discoverer	reference
BLM	Morgan, B. et al

notes:

note	Epsilon UMa. An Alpha CVn-type variable and eclipsing system.

data from Combined General Catalogue of Variable Stars (Vol. I-III) (Kholopov+ 1998)

position:

position (equinox 1950.0)

RA: 12h 51min 50.1sec

DEC: +56° 13' 51''

variability informations:

variability type	ACV	rotating variable star
magnitute at max. brightness	1.76
magnitute amplitude	0.02
photometric system	visual, photovisual or Johnson's V
epoch for maximum light [JD]	2426437.01 5. April 1931, 12:14:24 UT
period [d]	5.0887
next maximum light [JD]	2451809.2682 21. September 2000, 18:26:12 UT

spectral information

spectral class

A0p(Cr-Eu)

references

to a study	Vol. I GCVS (see Kholopov et al. 1985-1988)
to a chart/photograph	no chart is avaible, but the star is contained in the 'Bonner Durchmusterung'

miscanellous

ID in the GCVS catalogue	83/9005
constellation	Ursa Major
notes on existence	The star is equivalent to '0839014 ksi'.
There are notes in published catalog.

variability type description

variability type

description

ACV

Alpha2 Canum Venaticorum variables. These are main-sequence stars with spectral types B8p-A7p and displaying strong magnetic fields. Spectra show abnormally strong lines of Si, Sr, Cr, and rare earths whose intensities vary with rotation. They exhibit magnetic field and brightness changes (periods of 0.5-160 days or more). The amplitudes of the brightness changes are usually withine 0.01-0.1 mag in V. ACVO Rapidly oscillating Alpha2 CVn variables. These are nonradially pulsating, rotating magnetic variables of Ap spectral type (DO Eri). Pulsation periods are in the range of 6-12 mmag (0.004-0.01 days), while amplitudes of light variation caused by the pulsation are about 0.01 mag in V. The pulsational variations are superposed on those caused by rotation.