The Prix Jules Janssen is the highest award of the French Astronomical Society. Created in 1897 and awarded annually, it is usually given in alternate years to a French astronomer, and to an astronomer of another nationality. It is distinct from the Janssen Medal (created 1886), which is awarded by the French Academy of Sciences. Both awards are named for the French astronomer Pierre Janssen (1824-1907) (better known as Jules Janssen).
The above list is mostly sourced from the following external links: