This month’s segment of 365 Days of Astronomy called Singing the Ultraviolet Blues, and produced by me and Mark, is on ultraviolet astronomy. It’s one of those parts of astronomy that doesn’t get a lot of attention because … well, because you can’t SEE ultraviolet sources with the naked eye, and so they don’t “exist” for us. Yet, there they are — blazing away at wavelengths more energetic than our eyes can see. And, UV comes from everything from the Sun to distant quasars and all else in between. Want to see active starbirth in distant galaxies? Look for their UV radiation. It’s there!
Some galaxies, like M81 over there at the left, are brimming with stuff that’s giving off ultraviolet wavelengths. Everywhere you look, you’ll find UV emitting objects. But, it’s tough to do from Earth’s surface. Our atmosphere blocks most of the UV coming in, except for the few wavelengths that get through to give us sunburns.
So, in order to study these wavelengths of UV light that are given off by astrophysical objects, astronomers have been sending space-based instruments out beyond our planet. Their data have revealed the UV universe in exquisite detail.
Here are links to the UV missions and their teams. You can learn a lot just by browsing their pages to see what ultraviolet astronomy has revealed over the past decades.