NGC 7293
planetary nebula
The Helix Nebula is a planetary nebula (PN) located in the constellation Aquarius. Discovered by Karl Ludwig Harding, most likely before 1824, this object is one of the closest to Earth of all the bright planetary nebulae. The distance, measured by the Gaia mission, is 655±13 light-years. It is similar in appearance to the Cat's Eye Nebula and the Ring Nebula, whose size, age, and physical characteristics are in turn similar to the Dumbbell Nebula, differing only in their relative proximity and…