Revised MK Spectral Atlas
for Stars Earlier than the Sun

W.W. Morgan, H.A. Abt and J.W. Tapscott

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The Revised MK Atlas

Since its publication in 1943, the MKK Atlas has been the fundamental reference for the MK system of spectral classification of normal stars. In 1978, an update, for stars earlier than the Sun, was published in response to improved classification and observational techniques. This revised Atlas was distributed as a series of 32 photographic plates showing standard spectra for each class with accompanying notes. There is also a booklet giving some commentary on the MK system. As this Atlas is both rare and delicate, digital copies of both the plates and the booklet are here made available to the astronomical community. The MKK Atlas is also available from this site and should be read in parallel with the Revised MK Atlas.

Photographic Plates

Revised MK Atlas Booklet  (PDF  PostScript  G'zipped PostScript)

Preface to the ULO Version

This version of the Revised MK Atlas was produced by M. M. Dworetsky and W. R. Reece at the University of London Observatory, University College London, with permission from one of the authors, H.A. Abt.

While every effort has been made to ensure that this version of the Atlas is a faithful copy of the original, mistakes may have occurred. Please submit corrections to mmd AT

This version includes a table of contents and a star name index not included in the original version of the Atlas.

High resolution scans of the catalogue plates are available on the World Wide Web. The home page for these is /library/catalogues/mkrevised/. We thank Mr Sam Levison for performing the plate scanning.

University of London Observatory,
Mill Hill Park, London.
July 2004.

Copyright Information

This site, the electronic booklet and all plate scans are copyright University College London. Anyone wishing to mirror this site will need permission from University College London and H.A. Abt.

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