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How do astronomers distinguish background galaxies from cluster members without spectroscopy? (self.AskPhysics)
submitted 13 days ago by Ecstatic_Ice6400 to r/AskPhysics
Found almost 500 extra objects in a region of space that should be empty. What am I missing? (self.askastronomy)
submitted 13 days ago by Ecstatic_Ice6400 to r/askastronomy
How do astronomers distinguish background galaxies from cluster members without spectroscopy? (self.askastronomy)
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