B-type MK standard stars


The table below contains classification-resolution spectra of the whole set of updated MK standards and reference stars for the B spectral type, as defined in the paper A new grid of Northern standards for the spectral classification of B-type stars in the classical classification spectral range (Negueruela et al. 2024, A&A 690, A176; an improved version can be found at arXiv:2407.04163). If you find this page useful for your work, please cite this reference.

The spectra cover the 380–510 nm spectral region and have been artificially degraded to a resolving power R = 4000 (see the paper for details). Clicking on a star's name will display its spectrum in the plotting tool below the table. Marking the checkbox next to the name selects the spectrum for download. Any number of spectra can be downloaded in a single compressed file by clicking on Download Selected. The plotting tool can also be used to compare up to seven spectra on a single screen by clicking on Plot Selected.

Spectral Class

Spectral Class /Luminosity Classes

Plotting Tool


On this screen, you can display up to seven spectra of different standards for comparison. Each spectrum is drawn in a different colour. The user can set an offset between the spectra by using the corresponding boxes. Offsets are relative to the first spectrum in units of the continuum (all spectra are continuum-normalised to unity). The Auto Increment button will automatically introduce an offset of 0.1 units between spectra.