Aleph Prime was a city located on an asteroid in an unnamed star system. In the late 23rd century, just over 1 million people lived in Aleph Prime, who live in an area beneath the surface of the asteroid. As well as housing inside the asteroid, there was also room for a large plaza and park areas.

In 2270, Dr. Georges Mordreaux lived in Aleph Prime and began conducting experiments with transporting people back in time. (TOS novel: The Entropy Effect)