The Silhouette of a Protostellar Envelope
New stars are being born in the region of Swan Nebula (M17), another star-formation region that appears in this image as a bright nebula in the constellation Sagittarius. The Subaru Telescope looked at this region in infrared light and clearly captured the envelope of clouds covering the forming stars as a "silhouette." Further observation has led to a new discovery: the envelope has a complex, multi-layered structure. This study has unveiled the mechanism of how an envelope feeds material to a protostellar disk and will lead to a deeper understanding of the early stages of our solar system.