Charles Messier ( – ) was a
French astronomer most notable for publishing an
astronomical catalogue consisting of
deep sky objects such as
nebulae and
star clusters that came to be known as the 103 "
Messier objects". The purpose of the catalogue was to help
comet hunters, as he was, and to help other astronomical observers to distinguish between permanent and transient objects in the sky.
Messier's life
Messier was born in
Badonviller in the
Lorraine region of
France, being the tenth of twelve children of Francoise B. Grandblaise and Nicolas Messier, a
Court usher. Six of his brothers and sisters died while young and in 1741, his father died. Charles' interest in astronomy was stimulated by the appearance of the spectacular,
great six-tailed comet in 1744 and by an annular
solar eclipse visible from his hometown on July 25,
1748.
In 1751 he entered the employ of
Joseph Nicolas Delisle, the astronomer of the
French Navy, 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.
In 1764, he was made a fellow of the
Royal Society, in 1769, he was elected a foreignmember of the
Royal Swedish Academy of Sciences, and on June 30, 1770, he was elected to the
French Academy of Sciences.
Messier discovered thirteen comets :
His catalogue
The first version of Messier's catalogue contained 45 objects and was published in
1774 in the journal of the
French Academy of Sciences in
Paris. The final version of the catalogue was published in
1781, in
Connoissance des Temps for 1784. The final
list of Messier objects had grown to 103.
On several different occasions between 1921 and 1966, astronomers and historians discovered evidence of another seven deep-sky objects that were observed either by Messier or his friend and assistant,
Pierre Mechain, shortly after the final version was published. These seven objects,
M104 through
M110, are accepted by astronomers as "official" Messier objects.
The objects' Messier designations, from
M1 to
M110, still are in use by professional and
amateur astronomers today.
The catalogue is not organized scientifically by object type or by location, as the later
New General Catalogue would be. Nonetheless, the Messier catalogue 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 102 mm, or four 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 them. Professional astronomers still refer to objects by their Messier designation, and in amateur astronomy they are among the most frequently observed deep sky objects.
Many of the objects in the Messier catalogue were discovered by his assistant,
Pierre Mechain.
The crater
Messier on the
Moon and the
asteroid 7359 Messier were named in his honor.
Footnotes
Sources
- O'Meara, Stephen James (1998). Deep Sky Companions: The Messier Objects. Cambridge University Press.
- Biography at Students for the Exploration and Development of Space. Accessed July 2007
- by Jon Zander at OurDarkSkies.com . Accessed July 2007
- Professor Mark Brake and Martin Griffiths, Astrobiology Magazine European Edition, Spring 2007. Accessed July 2007
See also
