. . "109394797"^^ . . "planetary nebula"@en-us . "09394797-n"^^ . . "0"^^ . . "0"^^ . . . . "planetary nebula"^^ . . "a nebula that was once thought to be a star with its planets but is now thought to be a very hot star surrounded by an expanding envelope of ionized gases that emit a fluorescent glow because of intense radiation from the star"@en-us . "108805314"@en-us .