Spiru Haret

Spiru C. Haret 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.

15 February 1851

Born on the same birth day (15 February): Alexander Wurz • André Dumont (geologist) • Darrell Green • Erich Eliskases • Harold Arlen • James Marshall (cricketer) • Mark Canha • Mary S. B. Shindler • Milo Đukanović • Ronald Petrovický • Rui Patrício • Sax Rohmer • Sodapoppin • Steven Michael Quezada • Yehoshua Neuwirth • Álex González (shortstop, born 1977) • Óscar Freire

Born in the same month (February 1851): Durham Stevens • José Guadalupe Posada