Pretty Deep Maps: a detailed all-sky astronomical atlas

<p>The <em>Pretty Deep Maps</em> astronomical atlas&nbsp;is a large hyperlinked collection of charts and indices in PDF format covering the entire sky, in the main to&nbsp;a magnitude of 18, with star-dense sections at a lower magnitude, and selected regions to a deeper magnitude. The atlas is intended as a convenient, portable, deep visual representation of all-sky astronomical datasets, and can be used for tasks such as identification of objects in photographs and&nbsp;observation planning.&nbsp;The charts plot approximately 117k bright stars, 600 million field stars, 2.4 million galaxies, 277k variable stars, 110k multiple stars, 168k quasars, 8955&nbsp;galaxy groups, 5250&nbsp;galaxy clusters, 5004 dark nebulae, 2411 planetary nebulae, 1249 bright nebulae, 2167 open clusters, 159 reflection nebulae and&nbsp;157 globular clusters. The celestial sphere is divided into 6787 charts, each covering 3 degrees of declination at a map scale of&nbsp;11.74&quot; per mm. Charts employ a gnomonic projection. The charts are accompanied by a set of sortable indices.&nbsp;The atlas can be used on any device with a PDF reader capable of supporting within- and cross-document links.&nbsp;</p> <p>The dataset is described in&nbsp;a detailed technical document (guide.pdf).&nbsp;<br> &nbsp;</p>