<prompt> Bhala ukuqhubeka kwalesi sigaba - Ngo - 1920 kwaba nengxoxo - mpikiswano phakathi kuka - Harlow Shapley no - Heber Curtis i - Great Debate  <response>: , ngokuphathelene nemvelo yeMilky Way, i-spiral nebulae, kanye nobukhulu bendawo yonke. Ukuze asekele isimangalo sakhe sokuthi i-Great Andromeda Nebula iyinkanyezi engaphandle, uCurtis waphawula ukubonakala kwemizila emnyama efana namafu othuli eMilky Way, kanye nokushintsha okukhulu kweDoppler. 