1898 – Born on December 21st in Seneca Falls, New York. American astrophysicist whose explanation of the strong green emission from nebulae (clouds of rarefied gas) led to major advances in the study of celestial composition.
1921 – He taught physics at the California Institute of Technology.
1926 – At the age of 28, he published evidence that the entire universe is composed of the same elements that are found on earth.
1927 – His investigation of the ultraviolet spectra of highly ionized atoms led to his identification of the mysterious "nebulium" spectral lines of gaseous nebulae as forbidden lines of ionized oxygen and nitrogen.
1929 – Married to Mary Jane Howard on July 12th.
1931 – He became a professor in the California Institute of Technology.
1942 – Bowen was awarded the Henry Draper Medal of the National Academy of Sciences.
1946 – He was the director of the Mount Wilson Observatory.
1948 – He directed the completion of the Hale Telescope and the 48-inch Schmidt telescope and designed many of their instruments, including a novel spectrograph.
1973 – Died on February 6th in Los Angeles, California.