Hammer of Tulur

The Hammer of Tulur is a constellation of stars that sailors use to guide their ships, as it points the way north.

It is unknown if this constellation, and other cosmic bodies, returned to their previous orientation following the events of Ultima IX, or if it still points eastward.

Ultima Saga
In Lynn Abbey's Ultima Saga, three guide stars are used to locate true north in the sky. These stars could be the Hammer of Tulur, or at least a portion of it, used in the time immediately before Ultima V.

Trivia

 * This constellation serves the same purpose that sailors in our world use the North Star and Big Dipper.