Interstellar Distance Units

The Confederacy measures the distance between stars in an old unit which has been translated into English as the doppler. In GalCon it is represented by a rapid frequency shift from 3770 Angstroms to 7700 Angstroms in just under a second.
One doppler is very close to 0.19 light years in the parochial units favoured by Regulars before they joined the Confederacy, so dividing a doppler distance by five gives a reasonable (slightly overestimated) value for the distance in light years.