![]() ![]() ![]() It contains a lot of information, possibly more than some of the smart computerized guidance systems that some telescopes have.” (Kadri Tinn,, April, 2014) “The Star Atlas Companion fills an important niche. … this book is helpful for planning your observations and finding out more about the stars and constellations …. Herschel's classification of his nebulæ, and so on.“The Star Atlas Companion is a necessary addition to every amateur astronomer who is interested in how the stars and star clusters one might observe with a small to medium telescope would actually appear. The figure also includes instances of the mode of marking double, triple, and multiple stars, binaries (known or suspected), variables, Messier's nebulæ, Sir W. The way in which the constellation-names are introduced is also new, and seems preferable to the old arrangement, in which the name straggling over the whole constellation at once confused the star-grouping, and was itself almost illegible unless printed in very large letters. ![]() The arrow indicating precession in direction and magnitude (for 100 years) is a novel and very simple mode of exhibiting this important relation. It will be noticed that though this portion belongs to the outer portion of the map (where the distortion is greatest) the figures between the parallels and meridians are of their proper shape. The woodcut which gives (on a reduced scale and with inverted colours) a portion of Map 2 of the series (where it overlaps Map 4), exhibits some of the principal peculiarities of the new scheme. In fact, for the first time in the histoiy of star-mapping, a plan is adopted by which, with a moderate number of maps, there is no appreciable distortion or scale-variation. Owing to the equality of the maps and the choice of a central projection (the equidistant) the distortion is reduced to a minimum. The celestial sphere is to be divided according to this plan into twelve equal parts, each pentagonal in shape but, each map being made circular, there is a slight overlapping, which prevents any star-group from being broken off at the edge of a map, as in all the arrangements hitherto adopted. PROCTOR has planned a star-atlas on a plan which presents several advantages. ![]()
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