Catalogs
(Objects)
You
may have been asking yourself after spending a short time
on this site...what are these “M” objects. I mentioned M13,
M35, M81, M82, M104 and also listed NGC 3628. Where did
they come up with these numbers and prefixes?
Let’s
address the “M” objects first.
There was a man by the name of Charles Messier. He was a
French astronomer who lived from 1730-1817. Without going
into a great detail about his life, I would just say that
his passion in astronomy was comets. As he became more
proficient in the night sky he noticed other fuzzy objects
that he thought might have been comets, but over time these
objects did not move. To avoid confusion he began to label
these objects and thus began what we now call “Messier
Objects”.
On August 28, 1758 he observed a small patch in the
constellation Taurus. Realizing it was not moving, he
believed it to be nebula and not a comet. About a month
later it turned out to be his first entry into what is now
the Messier Catalog. He named it Messier 1 or M1 and later
it was named the Crab Nebula.
Over the years that followed he continued to log other
objects until he published his first catalog in 1774 which
included 45 objects. From 1774 to 1780 he added more to the
list which then totaled 68. His protege Pierre Mechain
added more to the catalog until in 1787 there were 103
objects. Later astronomers added seven more believing that
Messier himself had observed them. The present catalog now
stands at 110 objects.
The Messier catalog not only contains nebulas but star
clusters and galaxies as well. This catalog contains some
of the most impressive objects in the Northern Hemisphere
and it’s been labeled as the “greatest hits” of the night
sky.
Once a year around March/April it’s possible, if conditions
are favorable, to see all 110 objects in one night. Amateur
astronomers call this night a “Messier Marathon” and there
have been many people who have observed all 110 in one
evening. There are certificates you can earn by observing
various amounts in a designated period of time.
If you would like to know more about Charles Messier visit
the web at www.seds.org/Messier.
What
about “NGC”
Thousands of more objects have been observed and labeled
since Charles Messier. They chose not to add any more to
his catalog but rather started another catalog which is
called the “New General Catalog” or NGC. There are
thousands of objects in this catalog, many just as
impressive as the “M” objects. Depending on the charts or
maps you get many of the NGC objects will be listed along
with the Messier objects.
There are many catalogs available with information on NGC
and Messier objects but one of my favorites is the
“skyatlas 2000.0 Companion” by Robert A. Strong and Roger
W. Sinnott. I purchased mine at
sky
and telescope.com along
with the sky atlas maps. I find this book to be an
excellent resource of information not only for my needs but
also to share with others who may be just getting
interested in astronomy.
There are other indexes and listings available but I
believe this "skyatlas 2000.0 companion" with 2700 entries
will keep you busy for a long time.