What fundamental conclusion resulted from Edwin Hubble's 1925 publication regarding the Andromeda Nebula?

Answer

Andromeda was an independent galaxy, fundamentally changing the scale of the cosmos.

Hubble's finding that Andromeda was hundreds of thousands of light-years away—exceeding the size of the Milky Way—settled the Great Debate by proving Andromeda was an external galaxy, transitioning the view of the cosmos from one galaxy to a vast expanse of many.

What fundamental conclusion resulted from Edwin Hubble's 1925 publication regarding the Andromeda Nebula?
measurementHubblegalaxyDistanceCepheid