some amateur astronomers follow a quest that parallels the lifetime checklist of ardent birdwatchers: viewing every one of the objects in the "herschel 400". This is a radically truncated sample of the 2446 objects credited to william herschel in the last edition of the New General Catalog, made in 1976 as a challenge to amateur astronomers by the members of the ancient city astronomy club (st. augustine, florida). according to o'meara, all the objects are potentially visible in a 4" telescope, though the plague of urban and suburban light pollution means that many of these objects will be challenging to find for observers using a 6" or larger telescope. enter o'meara and his guide to help with any difficulties.
to encourage your persistence, o'meara provides a blank checklist at the back of the book where the reader can note the date and circumstances of each observation (nothing like a half completed list to keep up your resolve). the book itself is handsomely but efficiently formatted: divided first by seasons, and then by months, each month outlines seven nights of about 5 observations per night. there is a 3" square black and white photograph of each object, with an angular size scale included; the text for each entry includes a general description (curiously, this omits the date of discovery), instructs how to find the object, and describes its appearance in small and larger telescopes. high resolution star charts for each night are grouped on a single page, for easy reference, and o'meara even offers observing tips to capture very faint or difficult objects (of NGC6118: "averted vision, a dark sky, and lots of time breathing rhythmically and lightly tapping the telescope tube, to set the object in motion, will help to bring it out.") the introduction includes sketches of the typical appearance of each type of object (nebula, globular cluster, etc.), a list of constellations and their abbreviations, and a short discussion of visual magnitudes.
i was pleased to find a short biographical section on herschel, his sister caroline, the instruments they used and the difficulties they faced in making their historic deep sky discoveries. i visited herschel's home in bath, england, and welcome this salute to two fine astronomers, both for their own work and as representatives of the many innovative and often self trained scientist entrepreneurs of the 18th century.