OBAFGKM

Spectral classification

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This picture compares the spectra of different classifications of star, in the visual range from 400 to 700 nanometers (4000 to 7000 Angstroms). Thirteen regular types are shown, and at the bottom are three special cases, all selected from the spectrophotometric atlas by Jacoby, Hunter and Christian, 1984, which used data from the Kitt Peak National Observatory's 0.9-meter telescope.

From top to bottom, the stars and their type are: HD12993, O6.5; HD158659, B0; HD30584, B6; HD116608, A1; HD9547, A5; HD10032, F0; BD 61 0367, F5; HD28099, G0; HD70178, G5; HD23524, K0; SAO76803, K5; HD260655, M0; and YALE 1755, M5. The three special cases are HD94028, an F4 type but especially metal poor, SAO81292, an M4.5 with emission lines, and HD13256, a B1 with emission lines.

A labelled version of the image is also available (3072x1536 1.1Mb JPEG), or in two smaller versions (799x400 49kb JPEG or 400x200 18kb JPEG).

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