# Parsec

A Parsec is a unit of length used to measure the distance between stars.

## Description (Specifications)

The name parsec stands for "parallax of one second of arc", and allows calculating distances to nearby stars using simple observation and trigonometric parallax (apparent motion of an object due to change of position of the observer). It is one of the oldest Terran methods for measuring the distances to stars.

• A parsec is based on a baseline of 1 Astronomical Unit.
• The standard imperial abbreviation is pc.

### Equivalent Metrics

Other cultures have different values for a parsec:

### Term Usage Example

The Imperial world of Regina lies approximately one parsec from the non-aligned Ruie system.

## History & Background (Dossier)

The Solomani define one parsec to be the distance from Terra to a star that has a parallax of 1 arcsecond, and equals 3.261 light-years or 206,265 Astronomical Units.

Modern Imperial usage bases the parsec on the value of pi times light-years (one parsec is equal to 3.142 light-years)[1]. This is equivalent to a distance of 198,738 Astronomical Units, although for convenience and simplicity this value is generally rounded to 200,000 AU. The concept was adopted following the Solomani Rim War to avoid the use of specifically Terranocentric metrics.[2]

• By coincidence this distance is very close to the maximum distance a Jump-1 drive can jump.
• Because of this, 'parsec' has become the standard word used for this distance within the Imperium.
• Other races, using the orbital distance of their home world and different definitions of an arc second would derive different values for a parsec, but these wouldn't be Imperial parsecs.

## References & Contributors (Sources)

 This page uses content from Wikipedia. The original article was at Parsec. The list of authors can be seen in the page history. The text of Wikipedia is available under the Commons Attribution-ShareAlike 3.0 Unported License.