Description:
French astrophysicist Jules Janssen used spectroscopy to analyse the light spectra data from the solar prominences during totality. He observed the expected Fraunhofer lines due to presence of hydrogen and sodium in the Sun. However, he also noticed another emission line that did not align with any other known Fraunhofer lines. Months later, British scientist Norman Lockyer confirmed this observation and announced that this is due to an unknown element which we now call Helium.
