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Unformatted text preview: Trumpler (1920's): star counts are deceptive because of
Now ver y well characterize d w ith infrare d an d other
means. Stars, Galaxies and the Universe Maruša Bradač “Spiral Nebulae” known since 1700's
w ith telescopes of the time, not clearly different from planetar y
nebulae an d star -for ming regions
Kant (1755): “islan d universes” like the Milky Way?
Shapley an d Curtis debate d this hypothesis in 1920...how would
you ju dge it? M31 Stars, Galaxies and the Universe Maruša Bradač Argument in favor: This lo oks just like our mo del of the Milky Way,
so the Milky Way is just one of many.
Rebuttal: For something as large as the Milky Way to lo ok this
small, the universe would have to be unimaginably, ridiculously
large M31 Stars, Galaxies and the Universe Maruša Bradač Shapley-Curtis Debate Argument oppose d: a nova appeare d in M31, which had a large
apparent brightness, proving that M31 is not distant.
Rebuttal: all other novae in M31 were much fainter than the one
Shapley cites. Who you...
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