I detail each southern Gem in Chapter 2 – the heart of the book. Each object essay opens with a photograph of the target object (oriented with north up and east to the left) and a table of basic data. The data table includes the following: the Southern Gem number; common name(s), if any (note that many of these names are not officially sanctioned but rather fun monikers that reflect imaginings by me and/or other observers); NGC, IC, or other catalogue name; object type; constellation (Con); right ascension (RA) and declination (Dec) in equinox 2000.0 coordinates; apparent magnitude (Mag); surface brightness (SB) in magnitudes per square arcminute (for most objects); angular size or dimensions (Diam/Dim); distance (Dist); and the object’s discoverer (Disc) and date of discovery.

Beneath the table, you’ll find the discoverer’s catalogue description of the object, with its original catalogue number in parentheses at the end. In most cases, James Dunlop made the discovery, otherwise Dunlop’s description follows that of the discoverer(s). John Herschel’s catalogue description and catalogue number always follow Dunlop’s.

The catalogue number in parentheses at the end of each object description is a code – sometimes simple, sometimes a bit more complex. For instance, following Dunlop’s description of NGC 2546 (Southern Gem 37) is the code (D 563), which means that it is the 563rd object in Dunlop’s catalogue; the capital letter D stands for Dunlop. The code for NGC 2546 used by John Herschel is (h 3116), meaning it’s the 3116th object in John Herschel’s Cape Catalogue. (John Herschel uses a small “h” to differentiate himself from his father William Herschel, whose catalogue code is “H.”)