How old was Niels Bohr when he died?

Niels Bohr was 77 years old when he died on 18 November 1962.

Bohr was born in Copenhagen on 7 October 1885. Because his death came shortly after his 77th birthday, the age calculation is straightforward: he had completed 77 years and was a few weeks into his 78th year. He died at his home in the Carlsberg district of Copenhagen from heart failure.

Bohr had spent his career reshaping modern physics. His 1913 model of the atom introduced quantized electron energy levels, and his later work helped establish quantum theory and the Copenhagen interpretation. He received the Nobel Prize in Physics in 1922.

The nearby choices are plausible traps because Bohr lived well into the postwar scientific era and remained active in public discussions of nuclear energy. His son Aage Bohr later won the 1975 Nobel Prize in Physics, extending the family’s scientific legacy.