... One of the most identifiable nebulae in the sky, the Horsehead Nebula in Orion, is part of a large, dark, molecular cloud. ... This world was Earth's own Moon. ... Starburst Galaxy M94 . ... The Hercules Cluster of Galaxies . ... Also known as Abell 2151, this cluster is loaded with gas and dust rich, star-forming spiral galaxies but has relatively few elliptical galaxies, which lack gas and dust and the associated newborn stars. ... If Earth received this message from deep space, could we decode it...