Career
He worked at the Paris Observatory from 1879 to 1887, and as the assistant astronomer at the Algiers Observatory from 1887 to 1918. Sy was responsible for the discovery and naming of two asteroids, 858 El Djezaïr and 859 Bouzaréah. The names were drawn from locations near the Algiers Observatory.
He was awarded the Valz Prize (Prix Valz) in 1919 by the French Academy of Sciences.
The asteroid 1714 Sy was named after him in 1951.
