An avid reader of the works of
Camille Flammarion, he became a member of the
Société Astronomique de France in 1915 and made his first observations using the society's telescope on rue Serpente in Paris. He soon acquired a telescope and soon upgraded to a . From graduation in 1918 until 1929, he worked as a demonstrator at the
École Polytechnique and studied
engineering,
physics, and
chemistry at the
University of Paris. From 1920 until his death he worked for the
Meudon Observatory, where in 1930 he earned the title of
Joint Astronomer of the Observatory. After gaining the title, he earned a reputation of being an expert of polarized and monochromatic light. Throughout the 1930s, he labored to perfect the
coronagraph, which he invented to observe the
corona without having to wait for a solar eclipse. Most of this work implied painstaking long observations at the
Pic du Midi Observatory. It was an exceptionally good site, free of both air pollution and
light pollution but it came with a disadvantage: In the interwar period access to the peak implied mountaineering skills and physical fitness, especially in winter when access was only gained with a long and tiresome
ski touring trek on sealskin-fitted skis, a technique mastered by Lyot, a keen sportsman and mountaineer. Accommodation on site can only be described as spartan, before a powerline, a bigger refuge and a cablecar were built in the early 1950s. In 1938, he showed a movie of the corona in action to the
International Astronomical Union. In 1939, he was elected to the
French Academy of Sciences. He became Chief Astronomer at the Meudon Observatory in 1943 and received the
Bruce Medal in 1947. Lyot was the President of the
Société astronomique de France, the French astronomical society, from 1945-1947. He suffered a heart attack while returning from an eclipse expedition in Sudan and died on 2 April 1952, at the age of 55. ==Observations and Achievements on Pic du Midi==