Parsec/meta

Traveller star-maps all use hexs which are one parsec wide. The parsec also determines the range of the Jump Drive.

The original authors used Parsecs as a measurement for their maps over the more used (hence less sexy) light-years.

Many measures, such as this one are highly dependent on Earth's configuration. Eg. a circle is divided into 360 degrees because that was the number of days in a year in the Persian calender and/or has many factors. Division into arcminutes and arcseconds, each 1/60 of the degree is also highly dependent on the Earth time system, dividing an hour by 60s (note that 24 is also a factor of 360). Other races could use other circle divisions, 2520 has better factoring, pi, or radians. Even the light year only makes sense in a Terran context, as it is dependent on the time it takes earth to circle sol.