Glowing Waves Make 4

Credit: ESA/Hubble and NASA

Glow­ing waves of mate­r­ial ejected from a dying star trace out the num­ber four in this image of IC 4634 from NASA’s Hub­ble Space Telescope.

The end of a star’s life is any­thing but peace­ful. Once the fuel source of hydro­gen and helium run out for a star like our Sun, it swells to enor­mous size and becomes a red giant. Dur­ing this process, the star puffs off bub­bles of gas and becomes a plan­e­tary neb­ula. If the star is spin­ning, as seen with IC 4634, sym­met­ri­cal rings of mate­r­ial are thrown off. Far away from the star, S-shaped bars of mate­r­ial were flung off first. More recently, mate­r­ial was cast away as well as a donut-shaped bub­ble of gas. All that is left behind is the hot-white core of the dying star called a white dwarf. The intense ultra­vi­o­let light from this core causes the gas in the neb­ula to glow.

IC 4634 is located about 7,500 light-years away toward the con­stel­la­tion Ophi­uchus, the Ser­pent Holder. Plan­e­tary neb­u­lae have noth­ing to do with plan­ets. Astronomers search­ing for plan­ets in the 18th and 19th cen­turies encoun­tered many objects in the sky that had faint rounded disks sim­i­lar to the dis­tant plan­ets of Uranus and Neptune.