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The Perkins catalog of revised MK types for the cooler stars

Keenan, Philip C., McNeil, Raymond C.·1989·The Astrophysical Journal Supplement Series

Abstract

A catalog is presented listing the spectral types of the G, K, M, and S stars that have been classified at the Perkins Observatory in the revised MK system. Extensive comparisons have been made to ensure consistency between the MK spectral types of stars in the Northern and Southern Hemispheres. Different classification spectrograms have been gradually improved in spite of some inherent limitations. In the catalog, the full subclasses used are the following: G0, G5, G8, K0, K1, K2, K3, K4, K5, M0, M1, M2, M3, M4, M5, M6, M7, and M8. The irregularities are the price paid for keeping the general scheme of the original Henry Draper classification.

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Metadata

Authors
Keenan, P. C., & McNeil, R. C.
Venue
The Astrophysical Journal Supplement Series
Published
1989-10
Volume
71
Pages
245
ISSN
  • 0067-0049 (ISSN-L)
  • 1538-4365
OpenAlex
W2128791733
Cited by
372
References
0
Type
conference abstract
Language
en
Open access
closed

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CoChat. (2026). Citation check: The Perkins catalog of revised MK types for the cooler stars. https://app.cochat.ai/papers/10.1086/191373
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Keenan, P. C., & McNeil, R. C. (1989). The Perkins catalog of revised MK types for the cooler stars. The Astrophysical Journal Supplement Series. https://doi.org/10.1086/191373

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