SPACE.com invites experts in space exploration, science & technology to provide insightful commentary and informed perspective on news, current events, innovations, big ideas and ongoing research. Expert Voices includes Op-Ed analysis and opinion as well as interesting observations from the field and space exploration efforts around the world.
Nebulas come in all sorts of shapes, sizes, colors and configurations, from almost-perfect spheres and shells to dazzlingly complex helices to tangled wrecks. But where exactly do they come from? And, perhaps more importantly, where are they going?
We're told that the supreme iron law of the universe is that nothing can go faster than the speed of light, but astronomers have shown that some galaxies break that speed limit as they move away from us. What gives?