Joule is a lunar impact crater that lies on the far side of the Moon.

To the south is an outward projection that has the appearance of a crater partly overlain by Joule.

The interior floor is more level than the terrain surrounding the crater, but is marked by some small craterlets.

Only faint traces of this ray system actually cross into Joule, and are generally restricted to the western rim, inner sides and floor.

By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Joule.