Mitchel's career lasted barely two decades. His scientific contributions may seem relatively slight, but one must consider the difficulties he overcame. First, in order to validate his credentials as an astronomer he had to transform his observatory into a research institution, which eventually cost him community support despite the innovation and resiliency of the CAS. Second, the same qualities that made him a brilliant lecturer--his quick mind and powerful ego--led to conflicts with his peers that were difficult to reconcile, given the fluidity of antebellum scientific organizations. His mercurial relationships made it hard to undertake long-term research projects. His peers did, however, recognize his contributions--his election to the Royal Astronomical Society in 1850 proceeded from a solid contribution to astronomy. To view his life as reaching an apex in astronomy misses the mark: his first love was the stage, and applause motivated him more than income. His contemporaries honored him because they recognized that, despite his failings, he accomplished more than anyone had dreamed possible.
Philip S. Shoemaker, "Mitchel, Ormsby Macknight," American National Biography Online, February 2000, http://www.anb.org/articles/13/13-01147.html.