Star*Points for April, 2013
The Life of Comet Hunter Charles Messier

Last month's "comet watch" star parties at all Carroll County Library branches were a success.  Although clouds forced the watch to switch to the backup date, all libraries reported successful comet sightings made possible by volunteers from the Westminster Astronomical Society.  Images of Comet 2011-L4 (PanSTARRS) and watch participants were published in two editions of the Carroll County Times - in the following morning's daily and in last Sunday's paper.

Speaking of comets, Charles Messier (pronounced messy-yay) was an 18th century French comet hunter.  We've mentioned his name more than a dozen times over the years in this column, mostly in connection with selections from the catalog of celestial objects bearing his name.  All previous references have involved one object or another from that catalog.  Today, we look at the life of the man.

Born in 1730 in a region located in France's Vosges mountains, Charles Messier was the 10th of 12 children in a wealthy family.  Six children died at an early age and so Messier only knew five of his siblings.  After his father's death, when Messier was only 11, his eldest brother became head of the household.

Messier's interest in astronomy was stoked by his early observations, including the Great Comet of 1744 with six tails, and an annular - or ring -- solar eclipse he viewed from home in 1748.   At 21, and with his brother's help, Messier landed a job working for the Astronomer of the Navy in Paris. In this job he learned to use instruments and keep careful records.

In 1757 Messier began participating in the world wide effort to recover Comet Halley which was anticipated to return.  During this time he recorded observations of different objects, discovered by others, that would later become members of his catalog.  Those objects include that eventually became known as M31 and M32 - the Great Andromeda Galaxy and one of its dwarf companion galaxies.  

The following year Messier independently discovered his first comet although it was discovered earlier by someone else. However, during his observations of that comet Messier stumbled onto another comet-like object in the constellation Taurus. He continued observing it and noted that unlike comets it did not move.  It was not known at the time, but he had recovered a supernova explosion recorded by Chinese astronomers in 1054 A.D. The object, now known as the Crab Nebula, became the initial entry in Messier's list - M1.

Messier dove headlong into comet hunting, racking up a number of discoveries and co-discoveries.  He also continued with other observations, including a transit of Venus across the face of the sun in 1761.

Messier's first original non-cometary discovery was a globular star cluster in the constellation Canes Venatici.  With this discovery of M3, Messier became thinking about conducting an extended search for other similar objects as well as reviewing the catalogs already compiled by others.

He undertook correspondence with other astronomers and continued making discoveries of "false comets" on his own. In the meantime, Messier was appointed Astronomer of the Navy after the retirement of his predecessor.

In 1769 Messier began working diligently on the expansion of his catalog and was married the following year at age 40.

The first edition of the "Catalog of Nebulae and Clusters of Stars" consisting of 45 objects was published in 1771.  Later that year he and his wife relocated into the hotel where the Navy's observatory was located.  A son was born the following year, but he lived for only 11 days and the infant and his mother both died within three days of each other.

In 1781, Messier fell 25 feet into an ice cellar and became disabled for over a year.  Days after his recovery, Messier observed a transit of Mercury in 1782.  

Messier continued to observe clusters and nebulae and updated his catalog.  Final updates were made posthumously in the 20th century when several objects that were "lost" presumably due to recording errors or omissions by Messier himself were identified.  

During the French revolution and its bloody aftermath Messier remained in France, although he lost his salary and pension.  Later he was later honored by Napoleon who awarded him the Cross of the Legion of Honor in 1806. 

Charles Messier passed away in 1817, two years after suffering a stroke, and is buried in Paris' PŠre Lachaise Cemetery.

In his lifetime, Messier discovered 13 comets but his most honored achievement is his catalog of 110 non-cometary objects, most of which are easily visible in small to medium sized amateur telescopes.