One of the most active stellar nurseries in the galaxy has already given birth to thousands of stars, and is forming many more stars even now. Yet its days as a nursery are numbered, because its brightest stars are blowing away the supplies of gas and dust that make stars. IC 1396 stands about a third of the way up the northwestern sky at nightfall. It’s visible through binoculars high above Deneb, the bright star at the tail of the swan. IC 1396 is a complex of diffuse gas, dense blobs of gas, and newborn stars that spans dozens of light-years. A hot, vigorous star at its center, and a few others that are only slightly less impressive, produce enormous amounts of radiation. The energy heats the edges of dense blobs of gas and dust embedded in the cloud. The energy also creates shockwaves that travel through the blobs, causing pockets of gas and dust to collapse and form new stars. Most are found in two clusters, each of which contains many hundreds of stars of varying size, mass, and
