Translated from the original French by Bernard Sheehan; Edited and with an introduction by Dr. William Sheehan, a neuroscientist and amateur astronomer who is also a research fellow of the Lowell Observatory in Flagstaff, Arizona
Le Verrier was a superb scientist. His discovery of Neptune in 1846 made him the most famous astronomer of his time. He produced a complete theory of the motions of the planets which served as a basis for planetary ephemeris for a full century. Doing this, he discovered an anomaly in the motion of Mercury which later became the first proof of General Relativity. He also founded European meteorology. However his arrogance and bad temper created many enemies, and he was even fired from his position of Director of the Paris Observatory.

James Lequeux completed his PhD thesis in radioastronomy in 1962 and was an assistant, then associate, professor of physics and astronomy at Paris University until 1966. He was an Astronomer from 1966-1999 and an invited scientist at CalTech from 1968-1969. Dr. Lequeux was also the Director of the Marseilles Observatory from 1983-1988 and was Editor-in-Chief of the journal Astronomy & Astrophysics for 15 years. He retired in 1999 and then began work on the history of astronomy, a subject he presently writes about. Dr. Lequeux has published over 403 papers and four books, including The Interstellar Medium (Springer 2005).

The young years (1811-1845).- Neptune¿s discovery (1845-1846).- Waiting for the Paris Observatory (1847-1843).- Director of the Observatory (1844-1870).- The dictator.- The fall (1870-1872).- The second reign (1873-1877).- Longitudes via telegraph.- The creator of European meteorology.- Le Verrier¿s heritage.