(8 pages) The idea of multiple star systems came from observations and from data. Observations that a star's brightness changed, and data that measured these brightnesses and assigned them numeric values.
One way to mathematically analyze data is to plot a graph. Graphs are powerful in that they help expose patterns, & do it in a visual way.
In this activity, students are asked to use a model, and make a prediction before graphing the actual star system brightness data.