Explore these ideas and more!

Measuring parallax. (Image: Christine Guy Schnittka, Murphy & Bell)) To measure the distance of a star, astronomers use the same method as surveyors on Earth - triangulation. Stars show a slight change in position when viewed from two widely separated locations, usually opposite sides of the Earth’s orbit. This change in position is known as a parallax. The amount of parallax tells us the distance. Mona Evans, "Distances in Space" http://www.bellaonline.com/articles/art29665.asp