2005ApJ...622L.141M

We present Hubble Space Telescope NICMOS imaging of W3 IRS 5, a binary high-mass protostar. In addition to the two protostars, NICMOS images taken in the F222M and F160W filters show three new 2.22 µm sources with very red colors; these sources fall within a region 5600 AU in diameter and are coincident with an ∼100 M_☉, dense molecular clump. Two additional point sources are found within 0".4 (800 AU) of one of the high-mass protostars; these may be stellar companions or unresolved emission knots from an outflow. We propose that these sources constitute a nascent Trapezium system in the center of the W3 IRS 5 cluster containing as many as five proto-OB stars. This would be the first identification of a Trapezium still deeply embedded in its natal gas.