Geonomicon

The Geonomicon was a large catalog of worlds of the Prime Material plane that contained detailed information on almost a hundred planets in several different crystal spheres. It was considered a valuable source of information for explorers and spelljammer captains.

Description
By the mid-14 century DR, the Geonomicon collected information about approximately 80 different worlds. Each entry was divided into sections detailing general features of each planet, such as its size, composition, climate, gravity, and diurnal cycle, as well as the disposition of its landmasses, ecology, and sentient life forms.

Additionally, copies of the Geonomicon typically included dozens of blank pages at the end, which were meant for captains and adventurers to record information about worlds not yet covered by the book. On worlds with prominent spelljamming civilizations, it was possible for these additions to be submitted to the book editors and be included in subsequent copies. The contributing explorers' names would then be included among the list of authors.

History
In the mid-14 century DR, the half-elf Djan recalled information from the Geonomicon to identify the planet Garrash in Vistaspace from a description by Teldin Moore of a vision he obtained from an amulet connected to the Spelljammer.

Reputation
Spelljammer captains and adventurers regarded the Geonomicon as a great book and an invaluable resource. Copies were rare and extremely expensive, running at a price of at least 20,000 gp.

Appearances

 * Novels
 * The Broken Sphere