Astronomy Picture of the Day

Explanation: This pretty nebulalies some 1,500 light-years away,its shape and color in this telescopic viewreminiscent of a robin's egg.The cosmic cloud spans about 3 light-years, nestled securely within theboundaries of the southern constellation of the Furnace (Fornax).Recognized as a planetary nebula, egg-shaped NGC 1360 doesn't represent a beginning, though.Instead, it corresponds to a brief and final phase in theevolution of an aging star.In fact,visible at the center of the nebula, the central star of NGC 1360is known to be a binary star system likely consisting of two evolvedwhite dwarf stars,less massive but much hotter than the Sun. Their intense and otherwise invisible ultraviolet radiation has stripped away electrons from the atoms in their mutually surrounding gaseous shroud.The blue-green hue inside of NGC 1360 seen here is thestrong emission produced as electrons recombine withdoubly ionized oxygen atoms.