Spectra of K2I star (blue), K2III (orange) and K2V (green) stars at 4000—7000 angstroms, showing luminosity effects. Flux normalized to 5556 angstroms flux, spectra separated by 0.6 continuum units for clarity.
<a href="//commons.wikimedia.org/wiki/User:Vallastro" title="User:Vallastro">Vallastro</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>