Initial results from the Spitzer young stellar cluster survey

We report initial results from IRAC observations of four young stellar clusters. These regions are part of a larger Spitzer Space Telescope survey of 31 young stellar groups and clusters within 1 kpc of the Sun. In each of the four clusters, there are between 39 and 85 objects with colors inconsistent with reddened stellar photospheres. We identify these objects as young stars with significant emission from circumstellar dust. Applying an analysis developed in a companion paper, we classify these objects as either pre-main-sequence stars with disks (Class II) or protostellar objects (Class I). These show that the sites of recent star formation are distributed over multiparsec size scales. In two clusters, Cepheus C and S140, we find protostars embedded in filamentary dark clouds seen against diffuse emission in the IRAC bands.