Dubbed a Lyman-alpha blob, an enormous cloud of hydrogen gas spans several hundred thousand light-years in this remarkable image (left), a composite of x-ray, optical, and infrared data from space and ground based observatories.

Look up into the sky tonight, and even with a good telescope you won't come across a sight quite like this one. It is a familiar object though, the grand stellar nursery known as the Orion Nebula.