Massive Young Stellar Objects (MYSOs) are not found in isolation, but rather have a predilection for forming in clustered environments with other protostars. Therefore, the study of MYSOs necessarily requires the study of proto-clusters as a whole. Extended Green Objects (EGOs) are massive young protoclusters believed to be in an evolutionary state just prior to the emergence of UC HII regions - a phase which is critical for distinguishing between competing theories of massive star formation. I have been conducting a multiwavelength (near-infrared to radio) study of a sample of 9 nearby EGOs with the goal of determining source bolometric luminosity, massive-source multiplicity, and evolutionary state of the most massive protocluster members. In this talk, I will present results from our infrared (near-IR to submillimeter) analysis of source bolometric luminosity and mass, including how these results vary according to which radiative-transfer modeling package is used. I will also discuss source multiplicity as revealed by infrared through radio data, implications of the predominantly weak (several tens of uJy) and compact radio continuum flux densities measured towards these targets, and planned future projects exploring line emission from outflows in these EGOs.
Investigating the Early Stages of Massive Star Formation in Protocluster Environments: Multiwavelength Studies of Extended Green Objects