I have obtained one of the finest and least expected results—Spectra of the stars!—and beautiful spectra with colors and magnificent lines. Just one more step and the chemical composition of the universe will be revealed,” wrote astrophysicist Pierre Jules César Janssen to his wife from an observatory in Italy in December 1862. Armed with the latest technology of the day and observations made by other Western astrophysicists, Janssen was determined to pry open the secrets of the galaxy.
On August 18, 1868, Janssen managed to do just that. He became the first person to observe helium, an element never before seen on Earth, in the solar spectrum. At the time, though, Janssen didn't know what he'd seen—just that it was something new.
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