Discovery of Helium During the 1868 Eclipse
French astronomer Pierre Jules César Janssen observed a total solar eclipse from India, pointing a spectroscope at the Sun's atmosphere. He detected a yellow spectral line that matched no known element on Earth. British astronomer Joseph Norman Lockyer independently observed the same line and named the mysterious element 'helium' after the Greek word for Sun.
Scientists initially doubted that an element could exist only on the Sun. The finding challenged assumptions about the composition of celestial bodies.
Helium was eventually discovered on Earth in 1895, trapped in uranium ore. It became essential for cryogenics, medical imaging, and aerospace. The discovery demonstrated that eclipses could reveal entirely new physics.
The 2026 Antarctic eclipse continues the tradition of using rare observational windows to gather data impossible to obtain under normal conditions.