EXOPLANET LAB ACTIVITY FOR INTRODUCTORY EARTH SCIENCE STUDENTS USING NASA’S EYES ON EXOPLANETS

Since the discovery of the first exoplanet in 1995, dozens of new ones are being found every year (currently > 4000), making this an interesting and contemporary topic to include in introductory earth science classes. Data collected on exoplanets include not only location and distance from earth, but information such as radius, mass, composition, brightness, type (e.g., rocky, gas giant), distance from its star (orbital radius), and orbital period. A versatile, in-class lab activity created at Pasadena City College will be presented that uses NASA’s Eyes on Exoplanets (eyes.jpl.nasa.gov/eyes-on-exoplanets.html), a freely available computer visualization application. Students can fly through a fully rendered 3D universe and investigate over 1000 exoplanets known to orbit distant stars. Many of these were discovered during NASA’s Kepler mission that used the variability of light curves of stars to find patterns caused by exoplanets, which instructors can discuss as an interesting side-topic. The lab activity first familiarizes students with the program’s options and control features and then has them explore the data base. Students can visually compare the size of a star system they are examining, which can have six or more exoplanets, with the size of our solar system to compare relative spacing between planets and distances to the star. They can also superpose a shaded region called the habitable zonearound their star that shows the region where liquid water could exist. Questions in the activity prompt students to investigate extreme planets (largest, smallest, weirdest), latest discoveries, and specific planets by name, mission, and observatory. The culminating activity asks students to make a hypothesis about the following question and then search the data base to support or reject their hypothesis: When multi-exoplanetary systems have both Jovian and Terrestrial types of planets, which type of planet is typically closest to the star? This leads to very interesting discussions given what students have learned in class about the nebular hypothesis/theory of solar system formation, although it is also a simplification because there are more than two types of exoplanet that have been categorized. Students enjoy the exploration aspect of the activity, as well as the fact that they are looking at real data.