Armillary sphere

An armillary sphere was an astronomical model of the courses of the sun, moons, planets, and stars and of the principle celestial circles.

Description
Usually made of bronze, an armillary sphere held globes representing the sun or a planet such as Toril, surrounding by rotating concentric rings that might be mounted with their own spheres representing other planets.

Availability
Aurora's Whole Realms Catalogue sold an almost-flawless armillary sphere for 60 gp in the 1360s DR.

A Netherese armillary sphere of similar quality was valued at 100 gp circa 1479 DR.

Notable Armillary Spheres
Moonmaiden's Hall, a temple to Selûne in her navigational aspect in Murann, Amn, possessed an intricate armillary sphere large enough to have an altar and a priest at the very center.

Another massive armillary sphere existed in the Tomb of the Nine Gods under the city of Omu in Chult. This was large enough for people to sit inside the planets and operate it from within them, and on key conjunctions strange magical effects might occur.

Notable Owners
The retired mage Benelaius owned an armillary sphere at his home outside Ghars, Cormyr, circa 1367 DR. He once had to move quickly to save after one of his cats bumped it off a shelf.