Iridescent Eye

Credit: NASA & ESA

Shin­ing with iri­des­cent hues of red and blue, the Helix Neb­ula resem­bles an eye in this image from NASA’s Hub­ble Space Tele­scope. Plan­e­tary neb­ula come in all shapes and sizes. In the case of the Helix Neb­ula, and the Ring Neb­ula, we are look­ing down a trillion-mile-long bar­rel of gas and dust; all that is left over when the cen­tral star shed its outer lay­ers near the end of its life. A plan­e­tary neb­ula is the final stage of a Sun-like star’s life. As a star like our Sun reaches the end of its life, it bal­loons to a red giant star. While this gives the star new life, pro­vid­ing extra energy to burn it’s hydro­gen and helium fuel for nuclear fusion, it can­not last for­ever. Even­tu­ally the star col­lapses on itself. The outer lay­ers of the star are thrown into space cre­at­ing a bub­ble around the star.

The Helix Neb­ula, or NGC 7293, is one of the clos­est plan­e­tary neb­ula to Earth at only 650 light-years away toward the con­stel­la­tion Aquar­ius. Explore the comet-like tad­poles point­ing toward the super-hot white dwarf at the cen­ter of the neb­ula. These gas ten­ta­cles, float­ing in a sea of blue gas, form when the super-hot and fast solar wind plows into the cooler shells of dust and gas. Ultra­vi­o­let light from the hot cen­tral star causes the gas to glow. Explore also the color shifts through­out the neb­ula. Dif­fer­ent gases give off dif­fer­ent col­ors when excited by the pow­er­ful ultra­vi­o­let light.

Our Sun will not enter this stage of its life for another 4 bil­lion years giv­ing us plenty of time to study it and plan­e­tary nebula.