Electron shell jumping is an interesting phenomena of the Quantum world and one that interests me from the point of view of light (photon) passage. The interesting idea of the excited electrons in the calcium atom propulsion sequence was the colour of the 'agitated electrons' thus the photons given off. I would be interested to hear of any experimentation that associates atomic elements with laser excitation (to cause electron valence shell jumps) and the differences in photon colour generated as a consequence of the element atom stimulated. Likewise the phonon emissions and the possible detection of the heat magnitude for the different atomic elements.