Idea for Use in the Classroom

As a planetary scientist, Bethany Ehlmann makes observations about asteroids and dwarf planets that lead her to questions she can study. Often these questions compare what she observes to what she knows about how things work on Earth in order to see how asteroids are similar to or different from Earth. Facilitate a class discussion about what drives Bethany’s current research. Ask students, How does Bethany Ehlmann come up with the questions she wants to know more about? (possible answer: from her research and observations).

Have students work in small groups. After watching the video, use the photographs from The Planets to provide each group with a picture of Earth and one other planet. In their groups, have students use the photographs and additional research to compare and contrast the two planets in order to generate a list of their observations and questions.

After students come up with their questions, have them pick one question and develop a plan to investigate by running tests in a lab similar to Bethany Ehlmann. Support students as they identify a testable question and providing feedback as they design their investigation. Have groups share their questions and plans with the whole class and discuss both common and unique ideas across groups.

To conclude, have students reflect on what led them to their question (their observations) and how observing, asking questions, and planning investigations can be used in their daily life.


irregularly shaped planetary body, ranging from 6 meters (20 feet) to 933 kilometers (580 miles) in diameter, orbiting the sun between Mars and Jupiter.

dwarf planet

celestial body that is nearly spherical but does not meet other definitions for a planet.


to study or examine in order to learn a series of facts.


large, spherical celestial body that regularly rotates around a star.