Wax ka sii qor faqradan - Sanadkii 1920, Dooddii Weyneyd
dhexmaray Harlow Shapley iyo Curtis oo ku saabsanaa dabeecada Wadada Caanaha, Nebulae spiral ah, iyo cabirka caalamka. Si uu u taageero sheegashadiisa ah in Nebula weyn ee Andromeda ay tahay, xaqiiqdii, galaxy dibadeed, Curtis wuxuu sidoo kale xusay muuqaalka wadooyinka mugdiga ah ee ku dhex yaal Andromeda oo u ekaa daruuraha boodhka ee galaxy-keena, iyo sidoo kale aragtiyo taariikhi ah oo ku saabsan wareejinta Doppler ee muhiimka ah ee Galaxy Andromeda. Sannadkii 1922 Ernst Öpik wuxuu soo bandhigay hab lagu qiyaaso masaafada Andromeda iyadoo la adeegsanayo xawaaraha la cabiray ee xiddigaheeda. Natiijadiisa waxa ay dhigatay Nebula Andromeda meel ka baxsan Galaxy-deena masaafo u dhiganta qiyaastii. Edwin Hubble wuxuu xaliyay dooda sanadii 1925 markii uu markii ugu horeysay ku ogaaday xiddigaha cepheid ee galaxyada ka baxsan ee laga beddeli karo sawirada astronomical ee Andromeda. Sawiradan waxaa lagu sameeyay qalabka Hooker telescope, waxaana loo isticmaalay in la ogaado masaafada u dhaxeysa Nebula weyn ee Andromeda. Cabiritaankiisa wuxuu si cad u muujiyay in muuqaalkan uusan aheyn xiddig iyo gaas oo ku jira galaxyadeena, laakin gabi ahaanba galaxyada gooni ah oo ku taal meel aad uga fog Milky Way.