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1990-07-26
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Revised New General Catalogue of
Nonstellar Astronomical Objects
(RNGC)
One of the earliest catalogues of nebulous-appearing objects
was prepared in 1781 by the French astronomer Charles Messier
(1730-1817). Messier was a comet hunter, and as an aid to
himself and others in his field he placed on record 103 objects
that might be mistaken for comets. Because Messier's list
contains some of the most conspicuous star clusters, nebulae, and
galaxies in the sky, these objects are often referred to by their
numbers in his catalogue--for example, M31, the great galaxy in
Andromeda.
In the years from 1786 to 1802, William Herschel presented
to the Royal Society three catalogues, containing a total of
2,500 nebulae. The General Catalogue of Nebulae, published by
John Herschel in 1864, contains 5,079 objects, of which 4,630 had
been discovered by him and his father. The General Catalogue was
revised and enlarged into a list of 7,840 nebulae and clusters by
J. L. E. Dreyer in 1888. Today, most bright galaxies are known
by their numbers in Dreyer's New General Catalogue - for example,
NGC 224 = M31. Two supplements to the New General Catalogue,
known as the first and second Index Catalogues (abbreviated
"IC"), were published in 1895 and in 1908.
The Revised New General Catalogue of Nonstellar Astronomical
Objects (RNGC) (Sulentic and Tifft 1973) is a modern, revised,
and expanded version of the New General Catalogue of Nebulae and
Clusters of Stars (Dreyer 1888). While incorporating the many
corrections to the original edition found over the years, the
RNGC objects were verified on Palomar Observatory Sky Survey
(POSS) prints and plates for southern objects especially taken
for the purpose (about 90 southern objects could not be verified)
and are tied to the POSS where possible by the inclusion of
rectangular coordinates on the prints. New object description
are provided for objects which were examined during the course of
the work, Galactic coordinates are given, and new magnitudes are
reported along with their sources.
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