Astra was a planet, whose native inhabitants were known as the Astrans. In the 21st century, it was the core of the Astra Space Empire or Astran Empire, the closest space power to the solar system. There were frequent skirmish at the borders of the solar system between human space forces and Astran space fleets, ultimately resulting in a Space War in 2065. By the 25th century, however, the planet was home to an Earth colony.
The Astrans' capital city, located on Astra, was the city of Kapland.
On 5 June 2065, after the Kaplan of Astra was assassinated, the new Kaplan departed Unity City to return to Astra. (COMIC: The Amaryll Challenge)
By one account, an Earth colony was established on Astra 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)