Computers made their appearance during the 1950s, mainly in the United States. These machines were voluminous, complex and fragile, and less efficient than one of today’s pocket calculators. The Observatory acquired its first scientific computer, an IBM 650, in 1959. It would gradually revolutionize research, enabling long calculations to be made that had had to be done by hand with the help of logarithmic tables or with slow and noisy office calculators.

caption : The IBM 650 in Meudon - credits : Observatoire de Paris