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We use Spitzer Space Telescope observations from the Spitzer Survey of theSmall Magellanic Cloud (S3MC) to study the young stellar content of N66, thelargest and brightest HII region in the SMC. In addition to large numbers ofnormal stars, we detect a significant population of bright, red infraredsources that we identify as likely to be young stellar objects (YSOs). We usespectral energy distribution (SED) fits to classify objects as ordinary (mainsequence or red giant) stars, asymptotic giant branch stars, backgroundgalaxies, and YSOs. This represents the first large-scale attempt at blindsource classification based on Spitzer SEDs in another galaxy. We firmlyidentify at least 61 YSOs, with another 50 probable YSOs; only one embeddedprotostar in the SMC was reported in the literature prior to the S3MC. Wepresent color selection criteria that can be used to identify a relativelyclean sample of YSOs with IRAC photometry. Our fitted SEDs indicate that theinfrared-bright YSOs in N66 have stellar masses ranging from 2 Msun to 17 Msun,and that approximately half of the objects are Stage II protostars, with theremaining YSOs roughly evenly divided between Stage I and Stage III sources. Wefind evidence for primordial mass segregation in the HII region, with the mostmassive YSOs being preferentially closer to the center than lower-mass objects.Despite the low metallicity and dust content of the SMC, the observableproperties of the YSOs appear consistent with those in the Milky Way. Althoughthe YSOs are heavily concentrated within the optically bright central region ofN66, there is ongoing star formation throughout the complex and we place alower limit on the star formation rate of 3.2 x 10^-3 Msun/yr over the last ~1Myr.

The Spitzer Survey of the Small Magellanic Cloud: Discovery of Embedded Protostars in the HII Region NGC 346