8 February
1677: On 8 February 1677, Jacques Cassini was born.
Cassini was a French astronomer who made direct measurement of the proper motions of the stars which disproved the ancient belief in the unchanging sphere of the stars.
He also studied the moons of Jupiter and Saturn and the structure of Saturn's rings.
He was the son of astronomer Giovanni Cassini, with whom he made numerous observations. Eventually, he took over his father's duties as head of the Paris Observatory.
