MESSIER (LS): Messier Objects (19910619)
FILE: messier.ls
CONTENTS: Positions of Messier Catalog Objects
DATASET: This file comes in the basic dataset supplied with HyperSky. version 19910619. Availability on HyperSky CD-ROM: Vol. 1 (1993)
DESCRIPTION: This position-list lets you set your field position on any of the 110 objects generally recognized as part of the lists of the French comet hunter Charles Messier. The lists were published in four parts from 1771 to 1786. Objects 1-45 appeared in 1771 in the "Historie de l'Academie Royal des Sciences". In 1781 objects 46-68 appeared in the "Connaissance des Temps", followed in the same publication in 1784 by objects 69-103. Later objects were reported by Messier's colleague Pierre Mechain in the "Berliner Astronomiches Jahrbuch" in 1786.
The position-list is multi-level, allowing you to select a Messier object position in one of several ways. At the top level, you select a sublist based on numerical order, Right Ascension order, or type. The numerical and Right Ascension options then provide you with lists of the Messier objects in the appropriate order. The "type" option, however, presents you with a second-level menu based on Messier object type (ie, clusters, galaxies, planetary nebulae, etc). Once you pick the desired type, you are given a list of Messier objects of that type from which to choose.
Remember that this is only a position-list; it does not actually display an object at the position you select. The object you select will appear at the position only if you have also loaded a HyperSky datafile that contains it.