Deep-sky Companions: The Caldwell Objects (deep... Apr 2026

The Caldwell Catalogue, compiled by Sir Patrick Moore in 1995, serves as the definitive spiritual successor to the historic Messier Catalogue. While Charles Messier’s 18th-century list focused on objects that could be confused with comets from a Northern Hemisphere perspective, the Caldwell list identifies 109 spectacular deep-sky targets—including galaxies, nebulae, and star clusters—visible across both the northern and southern celestial spheres. Stephen James O’Meara’s seminal work, Deep-Sky Companions: The Caldwell Objects , provides the most comprehensive visual guide to these targets, blending meticulous sketches with historical and astrophysical insights.

In December 1995, Sir Patrick Moore published a list of 109 celestial objects in Sky & Telescope to address the gaps in the Messier Catalogue. Deep-Sky Companions: The Caldwell Objects Deep-Sky Companions: The Caldwell Objects (Deep...

Deep-Sky Companions: The Caldwell Objects Stephen James O’Meara Publisher: Cambridge University Press Subject: Observational Astronomy / Deep-Sky Catalogues Abstract The Caldwell Catalogue, compiled by Sir Patrick Moore