The planet is surprisingly Earth-like, with an 18-hour day and one diminutive moon. Circle sea is its biggest ocean. Its ecosystem includes velt of blue-green, knee-high ferns, and forest of bright alien colors.

Gummidgy is a jungle world popular with hunters. It is home to the Gummidgy Orchid-Thing, a sessile carnivore which hangs from trees and is a popular trophy for the wealthy. It orbits CY Aquarii, a blue giant SX Phoenicis variable star; due to the resulting high levels of ultraviolet light, most humans (except Jinxians) require melanin-boosting medication to venture outdoors. As the real world location of CY Aquarii is estimated at about 1300 light-years from Sol, far outside the "bubble" of Known Space it is suggested that the planet probably is in the Beta Lyrae system and not in the CY Aquarii system.

In 2647 it was very sparsely settled; its population including visitors was half a million. A weather dome protect the settlement from the sun's fierce ultraviolet radiation.

Sources: Grendel,

Other sites: Known Space Concordance, Larry Niven Wikia,