The Cat's Eye Nebula or NGC 6543, is a planetary nebula in the constellation of Draco. Structurally, it is one of the most complex nebulae known, with high-resolution Hubble Space Telescope observations revealing remarkable structures such as knots, jets, bubbles and sinewy arc-like features. In the center of the Cat's Eye there is a bright and hot star; around 1000 years ago this star lost its outer envelope, producing the nebula.---Wikipedia
Cartwheel Galaxy, ESO 350-40, is a lenticular galaxy about 500 mly away in the constellation Sculptor. It is an estimated 150,000 light-years across. The galaxy was once a normal spiral galaxy like the Milky Way before it apparently underwent a head-on collision with a smaller companion approximately 200 mya.
Nebula! This is a deep image of the Sword of Orion - the three stars that make up the weapon hanging off the belt of this famous celestial hunter. The image showcases the amazing mix of physical and optical processes including atomic emission, Rayleigh scattering, reflection and absorption of light, that go on in this star forming region to create this kaleidoscope of colors and details.