A planetary nebula (PN, plural PNe), is a type of emission nebula consisting of an expanding, glowing shell of ionized gas ejected from red giant stars late in their lives. The term "planetary nebula" ...
A nebula is a luminescent giant cloud of dust and gas in space that could be from a supernova or could be a star-forming region. The "dumbbell nebula," also known as Messier 27, is what astronomers ...
A fresh investigation of the planetary nebula NGC 6563 has revealed that its most unusual structures are far older than the ...