Transcripts of 10116_Small_Star_Life_Cycle_H264_1280x720_30

Music Music Music This kinesthetic activity models the life of a small to medium size star, such as our sun. Each person involved in this activity represents a bit of the material that goes into making such a star. As the activity begins everyone is dancing or moving around freely--just bits of matter that are hanging out in some particular spot in space. As these bits of matter come close to one another they start clumping together more and more, due to gravity. After a while this matter is clumped tightly enough to form a star. In our activity the participants at the edges form a ring facing inward, as the outer shell of the star, with their hands raised to represent the inwardly directed force of gravity. The participants in the center face outward, representing the core of the star, with their hands also raised to represent the energy generated by the fusion of hydrogen at the center of the star. These two forces remain in balance for most of the stars life. We call this a main sequence star. Eventually the star runs out of hydrogen to fuse in the core. And the balance of gravity and energy from fusion is broken. When this happens gravity wins and the participants in the core of the star drop their hands and move slightly closer together. The participants in the shell never lower their hands as gravity is always in effect. The slight decrease in the size of the core makes it hot and dense enough to start fusing helium. The participants in the core raise their hands once more as energy is again being generated at the center of the star. Participants in the shell take a step outward to represent the surge in energy, making the star larger than it was during the main sequence phase. The star has become a red giant. Finally, the core of the star runs out of helium to fuse. When this happens, the participants in the core once again drop their hands and move slightly closer together. This time the decreasing core size only raises the temperature enough to allow one last burst of energy, and push from the core. This causes the shell to drift away into space while the participants in the core move even closer together. At this stage the participants in the center represent a white dwarf while the shell has drifted off to become a planetary nebula. Eventually the material that once formed the shell of the star will be available to be used in the formation of another star. Music Music