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

4th Catalog of Orbits of Visual Binaries

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

catalogues and names

catalogues and names	Mira, o Cet, omi Cet, 68 Cet, HR 681, HD 14386, SAO 129825, BD -3 353, WDS 02193-0259Aa
constellation	Cetus

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

note (category: star names):

MIRA.

position, motion, parallax:

position (J2000)	RA: 2h 19min 20.7sec	DEC: -2° 58' 39''
position (B1900)	RA: 2h 14min 17.6sec	DEC: -3° 25' 54''
proper motion (J2000)	RA: -0.008 arcsec/a	DEC: -0.237 arcsec/a
radial velocity	64 km/s note: variable radial velocity
trigonometric parallax	0.024 arcsec
galactic coordinates	longitude: 167.75°	latitude: -57.98°

note (category: dynamical parallaxes):

0.0058". Masses A 15.7, P 4.0 solar.

magnitude

visual magnitude

3.04 (V on UBV Johnson system)

spectral / color information

spectral class	M7IIIe+Bep
B-V-magnitude	1.42
U-B-magnitude	1.09
R-I-magnitude
IR-note	object is infrared source (NASA merged infrared catalogue, Schmitz et al., 1978)

note (category: spectra):

Stratoscope II observations indicate infrared H2O bands. SiO maser source. Technetium found in spectrum. Also classified M5e-M9e.

note (category: colors):

The tabulated magnitude and colors refer to a time near maximum. Another determination at 6.99V gives B-V +1.56, U-B +0.12, R-I +3.08.

variability information

variable star identification

Omi Cet

note (category: variability):

Two variables: Mira and VZ Cet. Mira, ADS 1778A, M 2.0 - 10.1v, 331.96d; var. CO emission from circumstellar envelope. Speckle interferometry indicates large abrupt variation of diameter as a function of wavelength. Hydrogen lines vary on time scale of 1-2 days. Mira was discovered to be variable by Fabricius in 1596, the first such variable discovered. ADS 1778P, Ne "Novoides" class, VZ Cet, 9.5 - 12.0v, dBe.

double/multiple star system information

number of components of multiple star system	4
separation	118.7 arcsec
mag difference (of double or brightest multiple)	7.3
component ID	AC

note (category: double and multiple data):

AP var. M7IIIe, var. dBe, 400y, a = 0.85". The faint companion was first predicted in 1920 by Joy on the basis of a slightly displaced blue secondary spectrum. First seen by Aitken in 1923. Visible only when Mira is faint. Light variations on scale of hours superimposed by variations of 10-15 min. and rare flares of 2 min. duration. Components B, 13v at 73" and C, optical.

miscellaneous information

note (category: polarization):

Polarization possibly due to circumstellar dust scattering.

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

position, motion, parallax:

position (J2000)	RA: 2h 19min 20.787sec	DEC: -2° 58' 39.68''	±0.35 arcsec	source: 17
proper motion (J2000)	RA: 0.0001 arcsec/a	DEC: -0.24 arcsec/a		source: 25
radial velocity	64 km/s			source: 25
trigonometric parallax	0.024 arcsec		±0.002 arcsec	source: 25
galactic coord. (B1950)	longitude: 167.76°	latitude: -57.98°

magnitude:

visual

3.04 (observed)

source: 25

spectral information:

spectral class	M0		source: 96
Morgan-Keenan	M5.5-9IIIe+Bep		source: 25
B-magnitude	4.46 ±0.2	B-V-magnitude	1.42
U-magnitude	5.55 ±0.2	U-B-magnitude	1.09

variability information:

source of data: 30

variability type	180
var. amplitude	8.1
var. period	331.96
var. epoch	2444839 22. August 1981, 12:00:00 UT
next max light	2452474.08 18. July 2002, 13:55:12 UT

double/multiple star system information:

source of data: 19

separation between brightest and second brightest component	0.5 arcsec
position angle	116 °

component	magnitude	spectral class	catalogue(s)/name(s)
A	3.04	M0	Mira, o Ceti, 68 Cet, HR 681, HD 14386, SAO 129825
B	9.33	M0

sources:

17	ACRS
Corbin, T.E., and S.E. Urban, Astrographic Catalog Reference Stars, United States Naval Observatory, 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: 2h 16min 49.045sec	DEC: -3° 12' 13.39''	±0.009 arcsec
position (J2000)	RA: 2h 19min 20.729sec	DEC: -2° 58' 39.42''
proper motion B1950 (FK4)	RA: -0.0008 arcsec/a	DEC: -0.233 arcsec/a	±0.002 arcsec/a in RA ±0.002 arcsec/a in DEC
proper motion J2000 (FK5)	RA: -0.0005 arcsec/a	DEC: -0.237 arcsec/a
source of proper motion data	Determined by source catalog

magnitude:

visual	2 (accuracy: 1 decimal)
source of visual magnitude data	Source cited in source catalog introduction.

spectral information:

spectral class	M5e
source of spectral data	Taken from the Henry Draper Catalogue or no spectrum in source catalog.

remarks for duplicity and variability

Variable star in visual magnitude in source catalog

catalogues

source catalogue	GC, catalogue number: 2796
Durchmusterung	BD-03 353
Boss General Catalogue	2796
Henry Draper Catalogue	14386

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

position and proper motion:

position (J2000)	RA: 2h 19.3min	DEC: -2° 59'
proper motion (J2000)	RA: 0.002 arcsec/a	DEC: -0.24 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
Aa	1923	62	132°	0.9''	-	9.6	M7IIIe	JOY 1
	1993		116°	0.5''
Aa-B	1878	-	90°	74.7''	-	13	-	BU 1371
	1911		85°	73.1''
Aa-C	1782	18	92°	114.6''	-	9.3	-	H 1
	1925		78°	118.7''
Aa-D	1921	2	318°	148.3''	-	9.3	-	STG 1
BC	1911	1	69°	45.5''	13	9.3	-	H 1

discoverer information:

discoverer code	discoverer	reference
JOY 1	-	-
BU 1371	Burnham, S.W.	-
H 1	Herschel, W.	(Mem. R. Astron. Soc. 35, 21; 1867.)
STG 1	Struve, G.	-

notes:

note	Omicron Ceti. Prototype of the Mira-type variables. "Orbits" have been computed for the visual pair, but are most likely false. All distant companions are optical. B is a Cepheid, VZ Cet. H VI 1. C is BD-03@355.

data from 4th Catalog of Orbits of Visual Binaries (Worley+, 1983)

position:

position (B1900)

RA: 2h 14.3min

DEC: -3° 26'

magnitudes, spectral classes, orbital elements:

author:	P. Baize
date of observation:	1976
spectral class component B:	gM7e
spectral class component B:	gM7e
period [y]:	400
semi-major axis [arcsec]:	0.85
inclination [deg]:	111.3
node [deg]:	118.5
eccentricity:	0.66
time of periastron passage:	2001.5
dates of ephemeris:	1975-2000
grade:	indeterminate
reference:	Astron. Astrophys. Suppl. 39, 83; 1980.

notes

The primary is Mira Ceti. The companion is probably also variable.

other name(s)

JOY 1, Omicron Cet

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

position:

position (equinox 1950.0)

RA: 2h 16min 49sec

DEC: -3° 12' 13''

variability informations:

variability type	M	pulsating variable star
magnitute at max. brightness	2
magnitute at min. brightness	10.1
photometric system	visual, photovisual or Johnson's V
epoch for maximum light [JD]	2444839 22. August 1981, 12:00:00 UT
period [d]	331.96
next maximum light [JD]	2452474.08 18. July 2002, 13:55:12 UT
rising time	38 % of period

spectral information

spectral class

M5e-M9e

references

to a study	the main characteristics of the star was determined by the authors themselves
to a chart/photograph	Vol. I GCVS (see Kholopov et al. 1985-1988)

miscanellous

ID in the GCVS catalogue	21/9015
constellation	Cetus
notes on existence	The star is equivalent to '0220001 R'.
There are notes in published catalog.

variability type description

variability type

description

M

Mira (Omicron) Ceti-type variables. These are long-period variable giants with characteristic late-type emission spectra (Me, Ce, Se) and light amplitudes from 2.5 to 11 mag in V. Their periodicity is well pronounced, and the periods lie in the range between 80 and 1000 days. Infrared amplitudes are usually less than in the visible and may be <2.5 mag. For example, in the K band they usually do not exceed 0.9 mag. If the amplitudes exceed 1 - 1.5 mag , but it is not certain that the true light amplitude exceeds 2.5 mag, the symbol "M" is followed by a colon, or the star is attributed to the semiregular class with a colon following the symbol for that type (SR).