Charles Messier

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Charles Messier

Charles Messier (June 26, 1730April 12, 1817) was a French astronomer who in 1774 published a catalogue of 45 deep sky objects such as nebulae and star clusters. The purpose of the catalogue was to help comet hunters (like himself) and other astronomical observers to distinguish between permanent and transient objects in the sky.

Messier was born in Badonviller, Meurthe-et-Moselle, Lorraine, France, the 10th of 12 children of catchpole Nicolas Messier and Francoise b. Grandblaise. Six of his brothers and sisters died young, and in 1741, his father died. Charles interest in astronomy was stimulated by the appearance of a great 6-tailed comet in 1744 and by an annular Solar eclipse visible from his hometown on July 25, 1748.

In 1751 came under the employ of the astronomer of the Navy, Joseph Nicolas Delisle, who instructed him to keep careful records of his observations. Messier's first documented observation was that of the Mercury transit of May 6, 1753.

His catalogue

By 1781 the catalogue had grown to 110 'Messier Objects'. The objects' designations, from M1 to M110, are mostly still in use today.

The catalog is not scientifically organized by object type or by location (as the later New General Catalogue would be). Nonetheless, the Messier catalog comprises examples of every known deep sky object, including galaxies, planetary nebulae, open clusters, and globular clusters. Because these objects were accessible to the relatively small aperture telescope (approximately 102mm, or 4 inches) used by Messier to study the sky, they are among the most spectacular deep sky objects available to modern amateur astronomers using much better equipment. Furthermore almost all of the Messier objects are among the closest to our planet in their respective classes, which makes them heavily studied with professional class instruments that today can resolve very small and visually spectacular details in the them. Professional astronomers still refer to objects by their Messier designation, and in amateur astronomy they are among the most frequently visited deep sky objects. The "Messier Marathon," includes the Crab Nebula (M1) to a small elliptical galaxy near Andromeda (M110). In Messier marathons, many amateur astronomers compete to view all 110 of these objects in a single dusk-to-dawn session, usually in March, when conditions are most favorable. Many of the Messier objects can be seen in binoculars or small 50mm telescopes used as finders on larger telescopes. A few Messiers are naked eye objects: examples include a globular cluster, M13 in Hercules, and more readily, M31, the Andromeda Galaxy, as well as M42, the Orion Nebula, and M45, also known as the Pleiades or Seven Sisters.

Many of the objects in the Messier catalog were discovered by his assistant Pierre Mechain. The object designated M73 is an asterism, a Y-shaped figure of stars.

Some of the Messier objects have been so frequently photographed and reproduced that they are part of the popular culture. For example, the closing credit sequence of the 1960s show "The Outer Limits," included spooky music and a photograph of M104, an edge on galaxy bisected by a dark lane of dust. M104 is nicknamed "the Sombrero Galaxy."

The Messier crater on the Moon and the asteroid 7359 Messier were named in his honor.

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