The
Bayer designation
A Bayer designation is a stellar designation in which a specific star is identified by a Greek or Latin letter followed by the genitive form of its parent constellation's Latin name. The original list of Bayer designations contained 1,564 stars. ...
θ Orionis (Theta Orionis) is shared by several astronomical objects, located near
RA DEC :
*
θ1 Orionis (41 Orionis), the Trapezium Cluster, an open star cluster, the ''Orion OB Association 1d''
**
θ1 Orionis A (41 Orionis A, HD 37020, V1016 Orionis), a trinary star system
**
θ1 Orionis B (41 Orionis B, HD 37021), a quintet star system
*** θ
1 Orionis B West (COUP 766, MAX 97), an astronomical X-ray source
*** θ
1 Orionis B East (COUP 778, MAX 101), an astronomical X-ray source
**
θ1 Orionis C (41 Orionis C, HD 37022), a binary star system
**
θ1 Orionis D (41 Orionis D, HD 37023), a B0.5Vp variable star
**
θ1 Orionis E (COUP 732), a spectroscopic binary star system
**
θ1 Orionis F, a B8 variable star at 11th magnitude
**
θ1 Orionis G (COUP 826, MAX 116), a young stellar object
**
θ1 Orionis H (COUP 746, MAX 87), a young stellar object
*
θ2 Orionis (43 Orionis)
** θ
2 Orionis A (43 Orionis, HD 37041), a spectroscopic trinary
** θ
2 Orionis B (HD 37042), a B1V variable star
** θ
2 Orionis C (HD 37062), a binary star system
The various components are spread over several
arc-minute
A minute of arc, arcminute (arcmin), arc minute, or minute arc, denoted by the symbol , is a unit of angular measurement equal to of one degree. Since one degree is of a turn (or complete rotation), one minute of arc is of a turn. The na ...
s in and near the
Orion Nebula
The Orion Nebula (also known as Messier 42, M42, or NGC 1976) is a diffuse nebula situated in the Milky Way, being south of Orion's Belt in the constellation of Orion. It is one of the brightest nebulae and is visible to the naked eye in the nig ...
.
{{Set index article , astronomical objects
Orionis, Theta
Orion (constellation)