h Orionis

The object was found in the following catalogues:
  1. The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version)

  2. SKY2000 - Master Star Catalog

  3. Smithsonian Astrophysical Observatory Star Catalog

  4. The Washington Visual Double Star Catalog, 1996.0

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

catalogues and names h Ori, eta Ori, 28 Ori, HR 1788, HD 35411, SAO 132071, WDS 05245-0224A
constellation Orion

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

position, motion, parallax:

position (J2000) RA: 5h 24min 28,6sec DEC: -2 23' 49''
position (J1900) RA: 5h 19min 26,9sec DEC: -2 29' 21''
proper motion (J2000) RA: 0,002 arcsec/a DEC: 0 arcsec/a
radial velocity 20 km/s
note: spectroscopic binaries, double lined spectra
note: orbital data avaible
rotational velocity 46 km/s (uncertain) (variable)
trigonometric parallax 0,007 arcsec
note (category: radial and/or rotational velocities): Expanding circumstellar shell.
note (category: dynamical parallaxes): 0.005".


visual magnitude 3,36
(V on UBV Johnson system)

spectral / color information

spectral class B1V+B2e
B-V-magnitude -0,17
U-B-magnitude -0,92
R-I-magnitude -0,23

variability information

variable star identification Eta Ori
note (category: variability): EA + Beta C 3.31 - 3.60V, 3.14 - 3.35B, 7.989268d. Also sinusoidal pulsation period, amp. 0.05V, 0.30197 or 0.30145d.

double/multiple star system information

number of components of multiple star system 5
separation 1,5 arcsec
mag difference (of double or brightest multiple) 1,4
component ID AB
note (category: double and multiple data): ADS 4002A is SB triple system, abc with periods 9.2y and 7.989d. Speckle interferometry gives 9.219y, a = 0.036" for for ab x c. Visual components AB, binary, 3.8, 4.8v, sep. 1.650"; C, 9.4v at 115". The total mass of the quintuple system exceeds 50 solar masses, the most massive component being about 17 solar masses.
note (category: spectroscopic binaries): ab, 7.9841d, K 145.2k/s, V0 +35.9k/s, asini 15.9. abc, 9.2y, K 17.5k/s, V0 +19.5k/s, asini 805. Resolved by speckle interferometry at 4-meter Mayall telescope, sep. 0.04"; vsini secondary 39k/s.

miscellaneous information

note (category: group membership): Ori OB1a; Orion belt; cluster CR 70.

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

position, motion, parallax:

position (J2000) RA: 5h 24min 28,633sec DEC: -2 23' 49,38'' 0,43 arcsec source: 16
proper motion (J2000) RA: 0,0001 arcsec/a DEC: 0,001 arcsec/a source: 25
radial velocity 20 km/s source: 25
trigonometric parallax 0,007 0,001 arcsec source: 25
galactic coord. (B1950) longitude: 204,87 latitude: -20,39
GCI unit vector (J2000) X: 0,154242 Y: 0,987147 Z: -0,041824


visual 3,3 (observed) source: 31
photovisual 3,4 source: 2
photographic 3,2 source: 2

spectral information:

spectral class B1 source: 96
Morgan-Keenan B1V+B2e source: 25
B-magnitude 3,19 0,05 B-V-magnitude -0,17
U-magnitude 2,27 0,05 U-B-magnitude -0,92

variability information:

source of data: 30
variability type 10
var. amplitude 0,29
var. period 7,99
var. epoch 2415762
12. January 1902, 12:00:00 UT
next max light 2451629,11
25. March 2000, 14:38:24 UT

double/multiple star system information:

source of data: 19
separation between brightest and second brightest component 1,7 arcsec
magnitude difference between brightest and second brightest component 1
position angle 78


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: 5h 21min 57,676sec DEC: -2 26' 29,58'' 0,014 arcsec
position (J2000) RA: 5h 24min 28,638sec DEC: -2 23' 49,38''
proper motion J1950 (FK4) RA: -0,0002 arcsec/a DEC: 0,001 arcsec/a 0,002 arcsec/a in RA
0,002 arcsec/a in DEC
proper motion J2000 (FK5) RA: 0,0001 arcsec/a DEC: 0 arcsec/a
source of proper motion data Determined by source catalog


visual 3,4 (accuracy: 2 decimals)
source of visual magnitude data Combined magnitude of component stars.

spectral information:

spectral class B1
source of spectral data Taken from the HD with M stars reclassified by Miss Cannon.

remarks for duplicity and variability

Double star - see source catalog for source


source catalogue FK3, catalogue number: 200
Durchmusterung BD-02 1235
Boss General Catalogue 6655
Henry Draper Catalogue 35411

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

position and proper motion:

position (J2000) RA: 5h 24,5min DEC: -2 24'
proper motion (J2000) RA: 0,003 arcsec/a DEC: -0,001 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 1975 16 134 0,1'' 3,36 - B1V+B2e MCA 18
1988 116 -
Aa-B 1848 often 87 1'' 3,8 4,8 B1V+B2e DA 5
1989 78 1,7''
Aa-C 1904 3 51 115,1'' 3,4 9,4 B1V+B2e H 67
1977 52 116,1''

discoverer information:

discoverer code discoverer reference
MCA 18 McAlister, H.A. (Astron. J. 106, 1639; 1993.)
DA 5 Dawes, W.R. -
H 67 Herschel, W. -


note Eta Ori. A is a spectroscopic and eclipsing binary, P = 7.99d. A has been resolved into a third component by speckle interferometry. A spectroscopic period of 9.51y has been determined. H VI 67.

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


position (J1950) RA: 5h 21min 57,7sec DEC: -2 26' 30''

variability informations:

variability type EA+BCEP: close binary eclipsing system
pulsating variable star
magnitute at max. brightness 3,31
magnitute at min. brightness 3,6
photometric system visual, photovisual or Johnson's V
epoch for maximum light [JD] 2415761,826
12. January 1902, 07:49:26 UT
period [d] 7,989268
next maximum light [JD] 2451625,650052
22. March 2000, 03:36:04 UT

spectral information

spectral class B0.5Vea+B3V


to a study Vol. II GCVS
to a chart/photograph Vol. I GCVS (see Kholopov et al. 1985-1988)


ID in the GCVS catalogue 60/9007
constellation Orion
notes on existence The star is equivalent to '06090151omi 1'.
There are notes in published catalog.

variability type description

variability type description
EA 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.

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.

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.

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.
BCEP Variables of the Beta Cephei type (Beta Cep, Beta CMa), which are pulsating O8-B6 I-V stars with periods of light and radial-velocity variations in the range of 0.1 - 0.6 days and light amplitudes from 0.01 to 0.3 mag in V. The light curves are similar in shape to average radial-velocity curves but lag in phase by a quarter of the period, so that maximum brightness corresponds to
maximum contraction, i.e., to minimum stellar radius. The majority of these stars probably show radial pulsations, but some (V649 Per) display nonradial pulsations; multiperiodicity is characteristic of many of these stars.