In addition to his work on telescopes, Kuhn has also made contributions to the study of the Sun and its corona. He has developed various infrared instruments for solar and solar coronal spectroscopy and spectropolarimetry, and has used satellite experiments to study small changes in the Sun's shape and brightness. His work has led to a better understanding of the Sun's magnetic field and its role in solar activity, such as solar flares and coronal mass ejections.
