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We present infrared observations of the ultra-compact H II region W3(OH) madeby the FORCAST instrument aboard SOFIA and by Spitzer/IRAC. We contribute newwavelength data to the spectral energy distribution, which constrains theoptical depth, grain size distribution, and temperature gradient of the dustyshell surrounding the H II region. We model the dust component as a sphericalshell containing an inner cavity with radius ~ 600 AU, irradiated by a centralstar of type O9 and temperature ~ 31,000 K. The total luminosity of this systemis 71,000 L_solar. An observed excess of 2.2 - 4.5 microns emission in the SEDcan be explained by our viewing a cavity opening or clumpiness in the shellstructure whereby radiation from the warm interior of the shell can escape. Weclaim to detect the nearby water maser source W3 (H2O) at 31.4 and 37.1 micronsusing beam deconvolution of the FORCAST images. We constrain the flux densitiesof this object at 19.7 - 37.1 microns. Additionally, we present in situobservations of four young stellar and protostellar objects in the SOFIA field,presumably associated with the W3 molecular cloud. Results from the model SEDfitting tool of Robitaille et al. (2006, 2007} suggest that two objects (2MASSJ02270352+6152357 and 2MASS J02270824+6152281) are intermediate-luminosity (~236 - 432 L_solar) protostars; one object (2MASS J02270887+6152344) is either ahigh-mass protostar with luminosity 3000 L_solar or a less massive young starwith a substantial circumstellar disk but depleted envelope; and one object(2MASS J02270743+6152281) is an intermediate-luminosity (~ 768 L_solar)protostar nearing the end of its envelope accretion phase or a young starsurrounded by a circumstellar disk with no appreciable circumstellar envelope.

SOFIA/FORCAST and Spitzer/IRAC Imaging of the Ultra Compact H II Region W3(OH) and Associated Protostars in W3