Biography Pierre Mechain

    Pierre Méchain was born August 16, 1744 in Laon, France. He was the son of Pierre-François Méchain, who was an architect, and Marie-Marguerite Roze, and early in his life wanted to follow his father in a career in architecture. He studied mathematics and physics, but due to financial difficulties he ended up leaving college. He then became friends with Jérôme de Lalande, who allowed him to proof-read parts of the second edition of his book, L'Astronomie.  This landed him a job as an assistant hydrographer at the Depot of Maps and Charts of the Navy in Versailles.  Pierre Méchain’s fame as an astronomer would not have started if it had not been for becoming friends in 1774 with one of his fellow co-workers, Charles Messier. The two astronomers worked together to discover deep sky objects and cataloged them in Messier’s catalog. Méchain discovered two comets in 1781 and was able to calculate their orbits. With these same calculations he was able to prove that the comets discovered in 1532 and 1661 were actually two different comets.

In 1777, Méchain married Barbe-Thérèse Marjou whom he met while working in Versailles. They had two sons: Jérôme, and Augustin. After his intrigue in the study of comets and other space objects, Mechain made at least 30 considerable deep sky objects that were most likely nebulous compounds. He made 26 of these discoveries between 1779 and 1782.  His most famous comet discovery was of Comet Encke in 1786. It is the comet with the shortest period ever discovered. He discovered the Sunflower Galaxy, the Phantom Galaxy, the Spiral Galaxy M77, the Pinwheel Galaxy, and the Coma Pinwheel Galaxy. These are included in Messier’s catalog along with M72, M75, M78, M79, M85, M94, M95, M96. However after all these discoveries some of them were received with controversies, mostly because of other astronomers asking for credit in discovering these sky objects.  Méchain disclaimed his discovery of M102 as an erroneous re-observation of M101, thereby initiating a still open discussion on the true founder of this object. He is also accredited with discovering M104, M105, M106, M107.  He sent them to Bernoulli, the editor of the Berliner Astronomisches Jahrbuch at the time. Since these four objects were not contained in the original Messier catalog, they were attributed separately to Pierre Méchain, John Herschel, and J.L.E. Dreyer.

After Mechain announced to the public his discoveries he later dedicated his life to other astronomical discoveries.  In 1787, Méchain collaborated with J.D. Cassini and Legendre on measuring the accurate longitude difference between Paris and Greenwich. In 1791, Méchain undertook the southern part of a new survey of the meridian from Dunkirk to Barcelona, together with an assistant, Tranchot. However much of his work was impeded by the french revolution. He and his partner got arrested in Essone.  Pierre returned home and became a member of the new Academy of Science and the Bureau of Longitudes. He was unsatisfied with his work for finding the meridian, so he left Paris but died in 1804 after catching yellow fever.