Linked from
The 14 pages that link to Parsec, each with the reason it gives.
ParallaxBroader topic: Its definition converts a star’s parallax angle directly into distance.
Proper motionRelated: A star's distance in parsecs converts angular drift into transverse speed.
Stellar parallaxRelated: A star one parsec away has a parallax angle of one arcsecond.
Absolute magnitudeBroader topic: The standard distance in the definition is exactly 10 parsecs.
Stellar luminosityRelated: Distance is needed to infer luminosity from observed flux.
Distance modulusRelated: The distance-modulus formula expresses distance in parsecs.
Light-yearCompared with: Astronomers often use parsecs instead of light-years for stellar distances.
RigelRelated: Rigel’s distance is expressed in parsecs as well as light-years.