LAPLACE

Set to 3 different clues across 3 published puzzles, most often "Mécanique Céleste" astronomer — The New York Times, Friday, 11 July 2008.

7 letters

Every clue on record, most used first

"Mécanique Céleste" astronomeronce
The New York Times — Friday, 11 July 2008
French astronomer who wrote the seminal "Celestial Mechanics"once
The New York Times — Saturday, 17 March 2007
French pioneer in planetary orbital theoryonce
The New York Times — Saturday, 14 April 2001