Theta¹ Orionis C

Theta¹ Orionis C

Theta1 Orionis C and companions in the Trapezium cluster
Observation data Epoch J2000      Equinox J2000
Constellation	Orion
Right ascension	05h 35m 16.46375s[1]
Declination	−05° 23′ 22.8486″[1]
Apparent magnitude (V)	5.13[2]
Characteristics
Spectral type	θ1 Orionis C1: O6Vp[3] θ1 Orionis C2: B0V[4]
U−B color index	−0.95[2]
B−V color index	+0.02[2]
Variable type	suspected[5]
Distance		410 ± 20[7] pc
Absolute magnitude (MV)	−4.9[8]
Details
C1
Myr
C2
Mass	11 ± 5[4] M☉
Argument of periastron (ω) (secondary)		290.9 ± 2.5°
BD –05° 1315C
Database references
SIMBAD	data

Theta¹ Orionis consists of multiple components, primarily the four stars of the Trapezium cluster, all within one arc-minute of each other. Theta² Orionis is a more distant grouping of three main stars plus several fainter companions, 1-2 arc-minutes from Theta¹.

Theta¹ C is itself a binary of two massive stars, C1 and C2, plus a very close fainter companion apparently escaping the system.^[9]

Theta¹ Orionis C1 is responsible for generating most of the ultraviolet light that is slowly ionizing (and perhaps photoevaporating) the Orion Nebula. This UV light is also the primary cause of the glow that illuminates the Orion Nebula. The star emits a powerful stellar wind that is a hundred thousand times stronger than the Sun's, and the outpouring gas moves at 1,000 km/s.

References