Rubuta ci gaba don wannan sakin layi - Kafin zuwan cosmology na zamani, an yi magana mai yawa game da girman da siffar sararin samaniya. A cikin 1920, muhawarar Shapley <unk> Curtis
ya faru tsakanin Harlow Shapley da Heber D. Curtis a kan wannan batu. Shapley ya yi jayayya da ƙaramar sararin samaniya kamar girman Milky Way galaxy, kuma Curtis ya yi jayayya cewa sararin samaniya ya fi girma. An warware batun a cikin shekaru goma masu zuwa tare da ingantaccen lura na Hubble.