Key Terms
- cepheid
- a star that belongs to a class of yellow supergiant pulsating stars; these stars vary periodically in brightness, and the relationship between their periods and luminosities is useful in deriving distances to them
- light curve
- a graph that displays the time variation of the light from a variable or eclipsing binary star or, more generally, from any other object whose radiation output changes with time
- luminosity class
- a classification of a star according to its luminosity within a given spectral class; our Sun, a G2V star, has luminosity class V, for example
- parallax
- an apparent displacement of a nearby star that results from the motion of Earth around the Sun
- parsec
- a unit of distance in astronomy, equal to 3.26 light-years; at a distance of 1 parsec, a star has a parallax of 1 arcsecond
- period-luminosity relation
- an empirical relation between the periods and luminosities of certain variable stars
- pulsating variable star
- a variable star that pulsates in size and luminosity
- RR Lyrae
- one of a class of giant pulsating stars with periods shorter than 1 day, useful for finding distances
This book was adapted from the following: Fraknoi, A., Morrison, D., & Wolff, S. C. (2016). Key Terms In Astronomy. OpenStax. https://openstax.org/books/astronomy/pages/19-key-terms under a Creative Commons Attribution License 4.0
Access the entire book for free at https://openstax.org/books/astronomy/pages/1-introduction
