Abstract:Josef Johann von Littrow, Austrian astronomer in the early 19 th , and Rudolf Kippenhahn, German astrophysicist in the late 20 th century, were both quite successful as authors in popularizing astronomical topics. Subject of the following essay will be a discussion about some questions of which nearly all, during Littrow's lifetime , were not yet resolved. Kippenhahn, some hundred and fifty years later, could give the solution of many of them. But really of all?
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