Theta1 Orionis D

For other stars with this Bayer designation, see θ Orionis.
θ1 Orionis D

Theta1 Orionis D and companions in the Trapezium cluster
Observation data
Epoch J2000      Equinox J2000
Constellation Orion
Right ascension 05h 35m 17.24645s[1]
Declination −05° 23′ 16.5707″[1]
Apparent magnitude (V) 6.70[2]
Characteristics
Spectral type B1.5 Vp[3]
U−B color index −0.71[2]
B−V color index +0.09[2]
Astrometry
Radial velocity (Rv)+32.4[4] km/s
Proper motion (μ) RA: +1.822[1] mas/yr
Dec.: _0.393[1] mas/yr
Parallax (π)2.2820 ± 0.0207 mas[1]
Distance1,430 ± 10 ly
(438 ± 4 pc)
Absolute magnitude (MV)−3.3[5]
Details
Mass18±6[5] M☉
Radius5.6±0.8[5] R☉
Luminosity29,500[5] L☉
Surface gravity (log g)4.2±0.1[5] cgs
Temperature32,000±1,000[5] K
Rotational velocity (v sin i)49.0±0.9[5] km/s
Age2.5±0.5[5] Myr
Other designations
θ1 Orionis D, 41 Orionis D, HR 1896, HD 37023, HIP 26224, WDS J05353-0523D
Database references
SIMBADdata

Theta1 Orionis D (θ1 Orionis D) is a member of the Trapezium open cluster that lies within the Orion Nebula. It is a B class blue main sequence star with several faint companions.

θ1 Orionis consists of multiple components, primarily the four stars of the Trapezium cluster (A, B, C, and D) all within one arc-minute of each other. θ2 Orionis is a more distant grouping of three main stars plus several fainter companions, 1-2 arc-minutes from θ1.

θ1 D itself has a faint optical companion 1.4" away and a spectroscopic companion in a 40-day orbit. Infrared Optical Telescope Array observations suggest another companion at 18.6 mas.[6]

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  2. ^ a b c Cite error: The named reference ducati was invoked but never defined (see the help page).
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