The List of mnemonics for star classification reference article from the English Wikipedia on 24-Apr-2004
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List of mnemonics for star classification

The following is a list of mnemonics for stellar classification. Stars are classified as O, B, A, F, G, K, M, and sometimes R, N, S, C, L and T depending on their size and composition. The classifications R, N, S and C are given to stars with high carbon content and L and T are given to stars that are so small they do not generate enough heat to begin nuclear fusion. These "unusual" classifications are usually not included in mnemonics.