The folks at Hubble just released this picture, in time for the Fourth of July:
That is a seriously cool image. It shows a ribbon of gas, compressed and glowing due to a shock wave that slammed into it. The shock came from Supernova 1006, a star that detonated 7000 light years away from us. This was not a massive star that exploded, but a low-mass white dwarf, the dense core left over when a star like the Sun runs out of fuel. Still, the forces are roughly the same, with a titanic explosion ripping the star apart and creating eerie, unearthly beauty even in death.
White dwarfs don't have much if any hydrogen in them. The gas in the image is mostly hydrogen (that's what gives it that red hue), meaning this material must be just random gas floating in the galaxy that got in the way of the expanding blast wave. The remnant itself, the expanding debris from the supernova, is now so spread out -- it's 60 light years across! -- that it's mostly invisible to telescopes. But the wave is still moving outward at about 10 million kph, so when it hits gas like this the matter compresses and glows.
I enhanced the color and contrast of the image a bit here to show off the incredibly narrow filaments in the ribbon, as well as letting you see faint background stars and even a galaxy or ten way off in the background. Too bad there aren't any obviously blue stars or galaxies in the image, given the holiday. Oh well, the universe doesn't care much for our mundane lives or freedoms. But it's those very things that allow us to observe the universe -- and it's the explosive fireworks of supernovae events like SN 1006 that created the calcium in our bones and the iron in our blood, scattering them throughout the galaxy, where they could gather in gas clouds, which formed stars, planets, and eventually, us.
Remeber: when we look out, we look in. That's one of the many reasons science is so cool.