Studies of Extremely Young Clusters. III. IC 5146.

Three-color photoelectric and photographic observations of stars in IC 5146 have been obtained to about V = 17. The color-magnitude diagram, like those for NGC 2264, NGC 6530, and the Orion Nebula cluster, consists of a normal main sequence from B1 to about A0, beyond which the stars lie above the main sequence and are presumably still in the gravitational contraction stage. Like these other ekisters, IC 5146 contains a number of faint variable stars, presumably late-type Orion variables.