Theta1 Orionis D
# Theta1 Orionis D

$Theta^1$ Orionis D $(θ^1$ 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.

$θ^1$ 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. $θ^2$ Orionis is a more distant grouping of three main stars plus several fainter companions, 1-2 arc-minutes from $θ^1.$

$θ^1$ 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.

