Spiru Haret

Spiru C. Haret (Romanian pronunciation: [ˈspiru haˈret]; 15 February 1851 – 17 December 1912) was a Romanian mathematician, astronomer, and politician. He made a fundamental contribution to the n-body problem in celestial mechanics by proving that using a third degree approximation for the disturbing forces implies instability of the major axes of the orbits, and by introducing the concept of secular perturbations in relation to this. As a politician, during his three terms as Minister of Educat...