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> Eighty years after the discovery of dark matter... This is me being pedantic, but when was dark matter 'discovered'?

• foxyv 9y ago
  I think they are referring to the first observation of differences between empirical evidence and our models that lead to the concept that we call dark matter. Unfortunately cosmology usually doesn't have discoveries so much as unanswered questions and speculation. But yeah, discovered isn't really the right word is it?
• antognini 9y ago
  They're probably referring to Fritz Zwicky's observation in 1933 that the luminous matter in the Coma Cluster couldn't support the observed velocity dispersion. Zwicky hypothesized that there was a large amount of non-luminous matter that allows the velocity dispersion to be as large as it is. Zwicky's hypothesis wasn't taken seriously until the 1970s when Vera Rubin and others found a similar effect in galactic rotation curves.