When the moon blocks the sun and day turns to night on April 8, the sky will take on an otherworldly appearance for those in the path of totality — the roughly 115-mile-wide swath from Texas to Maine. Stars will emerge from their midday slumber, the horizon in all directions will be bathed in a peachy twilight, and — spectacularly — the solar corona will shine from behind the jet-black silhouette of the moon.