Were Galileo Galilei and Antonie van Leeuwenhoek alive at the same time?
Yes. Galileo Galilei and Antonie van Leeuwenhoek were alive at the same time for 9 years, from 1632 to 1642.
Galileo Galilei was 68 when Antonie van Leeuwenhoek was born.
Antonie van Leeuwenhoek was 9 when Galileo Galilei died, aged 77.
Antonie van Leeuwenhoek
Dutch scientist known as "the Father of Microbiology", and one of the first microscopists
Born 24 October 1632 · died 26 August 1723, aged 90