... An Extraordinary Spiral from LL Pegasi . ... Credit Copyright: ESA , Hubble , R. Sahai ( JPL ), NASA Explanation: What created the strange spiral structure on the left? No one is sure, although it is likely related to a star in a binary star system entering the planetary nebula phase, when its outer atmosphere is ejected. ... NASA Official: Jay Norris. ... Publications with keywords: planetary nebula . Publications with words: planetary nebula . ... The Red Rectangle Nebula from Hubble . ...