Taken prior to the decommission of Hubble's Wide Field Planetary Camera 2 in 2009, this image focuses in on a region found about 4,500 light-years from Earth in the constellation of Carina.
Called Kohoutek 4-55 (otherwise known as K 4-55, after the individual who initially discovered it, Czech astronomer Luboš Kohoutek), this is a planetary nebula by nature, which means its existence was only made possible when a medium-mass star died. Unlike large stars, when Sun-like stars die, they do not explode. Instead, they swell hundreds of times larger than their original size (a period of stellar evolution called the red giant phase), before they shrink back down to size. Ultimately, they lose a significant quantity of their stellar envelope, which go on to form the nebula itself.
They come in all different shapes, sizes and colors, but most exhibit similar characteristics. Take K 4-55: it looks remarkably similar to two well-known nebulae: the Helix Nebula and the Ring Nebula. The difference is, K 4-55's central region—where the now-dead star, a white-dwarf, resides—is rather misshapen (the circular nature of the other two helps give them an eye-like quality).
Other characteristics include a bright inner ring, and a more asymmetric outer layer. They, in turn, are strange in the fact that they are surrounded by another layer, which glows as a result of ionized nitrogen gas.
See a larger image here.