article_snippet: So the ratio between the orbital period of the first and second planet is the same as the ratio between the second and the third planet and so on.
article_snippet: This means if you know how long it takes for some of the planets to orbit around a star, you can calculate how long it takes for the planets to orbit and can calculate the planets position in the planetary system.
article_snippet: Because of this, if you know how long this takes some planets to circle a star, you can work out the time taken for other planets to orbit and fix other planets positions in the planetary system.
article_snippet: Light curves of the some of the planets orbiting the star Kepler-62.
article_snippet: the Kepler satellite observes exoplanets by measuring the light curve of a star.