An Astral Plane is a level of existence tethered to reality but also set apart. Those who travel through the astral plane experience time differently, allowing some to fast-travel across real-space such as The Lamb of The Imperium.
Main article: The Lamb
The Lamb uses a special jump drive to move through an astral plane to cover massive distances in the span of minutes. It isn't as fast as a Bagon Noz Drive, which allows ships to travel through Tartarus, but is is nicer and safer[Tales 1].