The Laniakea Supercluster (/ˌlæni.əˈkeɪ.ə/; Hawaiian for “open skies” or “immense heaven”) is the galaxy supercluster that is home to the Milky Way and approximately 100,000 other nearby galaxies.
Nuclear bomb detonation produces a small amount of local I-131 fallout. Most I-131 distributes over large distances, typically with only 10% making its way to the earth’s surface before undergoing spontaneous radioactive decay to stable xenon-131.