In this activity, students are reminded that the Universe is made up of elements and that the heavier elements are created inside of a star, as they learned in the "Elements and You" activity. They are introduced to the life cycle of a star and to... (View More) the way in which a star's mass affects its process of fusion and eventual death. Students discuss the physical concept of equilibrium as a balancing of forces and observe an experiment to demonstrate what happens to a soda can when the interior and exterior forces are not in equilibrium. An analogy is made between this experiment and core collapse in stars, to show the importance of maintaining equilibrium in stars. Finally, students participate in an activity which demonstrates how mass is ejected from a collapsed star in a supernova explosion, thereby dispersing heavier elements throughout the Universe. This activity is part of a series that has been designed specifically for use with Girl Scouts, but the activities can be used in other settings. Most of the materials are inexpensive or easily found. It is recommended that a leader with astronomy knowledge lead the activities, or at least be available to answer questions, whenever possible. (View Less)

In this lesson, students explore a discrepant event when they design an experiment to measure the rate that ice melts when in pure water versus salt water. It is designed to help students realize that a carefully-designed experiment may yield... (View More) unexpected results, due to unseen events, even though the experiment is precisely planned and executed. The addition of a new technology may clarify factors in the experiment which were previously unknown. Note: the experiment requires advance preparation the day before: two buckets of water are set-up (one with plain tap water, the other with as much salt dissolved in it as possible), which need to be at room temperature. It also requires ice cubes of uniform shape (e.g., from an ice maker or ice trays filled to uniform capacity). This lesson is part of the Cosmic Times teachers guide and is intended to be used in conjunction with the 1993 Cosmic Times Poster. (View Less)

In this lesson, students will explore the density of substances as a model for understanding the mass to light ratio as a predictor of dark matter. They will measure and calculate mass and volume to calculate the density of a foam ball. Students... (View More) will try to explain a discrepant event when data is not as expected (in this case a nerf ball that seems too heavy for its volume). Students will then use the concept of density, a ratio of mass to volume, to attempt to explain the mass to light ratio for luminosity and gravity. Advance preparation required. Materials needed for this activity include: small foam balls, tape measure, triple beam balance for each group, posterboards/construction paper, and markers (estimated materials cost doesn't include triple beam balances). This lesson is part of the Cosmic Times teachers guide and is intended to be used in conjunction with the 1965 Cosmic Times Poster. (View Less)