Astra was a planet that was home to an Earth colony.
The colony was established at some point after the 23rd century. (AUDIO: The Suffering)
In 2493, Vicki and her widowed father left Earth for Astra, but they never arrived. The ship they took, the UK-201, crash-landed on Dido. (TV: The Rescue)
Like many of Earth's colonies at the time, Astra was a terrible place. (PROSE: Christmas on a Rational Planet)