Qor faahfaahin faahfaahsan oo ku saabsan faqradan - ka hor inta aan la fahmin in galaxyada wareega ay ka jiraan meel ka baxsan galaxyada Milky Way, waxaa badanaa loo yaqaanay "nebulae wareega". Su'aasha ah in waxyaabaha noocaas ahi ay yihiin galaxy-yo gooni ah oo ka madax banaan Milky Way, ama nooc ka mid ah nebula oo ka jira galaxy-deena, ayaa ahaa mawduuca doodda weyn
1920-kii, Heber Curtis oo ka tirsan Lick Observatory iyo Harlow Shapley oo ka tirsan Mt. Xarunta kormeerka ee Wilson. Laga soo bilaabo 1923, Edwin Hubble wuxuu arkay Cepheid variables dhowr nebula spiral ah, oo ay kujirto waxa loogu yeero "Andromeda Nebula", isagoo cadeeyay in ay yihiin, run ahaantii, galaxyada oo dhan oo ka baxsan kuweena. Ereyga "Nebula spiral" tan iyo markaas lama isticmaalin.