Hobbies And Interests
Formation
Star formations are very complex. Interstellar clouds experience gravitational collapse, which creates a rotating gas globule. The globule continues to collapse, causing an exponential increase in temperature as the globule spins faster. The globule develops a central core and a disk of dust that surrounds it, with the disk eventually turning into planets and asteroids. Teachers can describe the ways in which the star forms. Then, the students can work in groups to create a storyboard that shows the process of the star forming. At each stage depicted in the storyboard, the students can note the temperature that the star must reach to enter into that state.
Building Pressure
Students might wonder why a bunch of gas clouds in space get so hot. The gas sphere that eventually becomes the sun reaches an enormous temperature because the gravity of the particles pulls them closer together, creating pressure that raises the temperature of the star. Help students understand the relationship between pressure and temperature by measuring the temperature of carbonated soda in a half-full bottle. After measuring the temperature, the students can shake up the bottle and then measure the temperature again, recording the change in temperature resulting from the increased pressure in the bottle.
Main Phase
The star undergoes nuclear fusion, which releases an enormous amount of heat and light. The globule begins fusion at about 20 million degrees Fahrenheit. Explain to the students that the sun sends light and heat into space in all directions, but that enough heat and light radiates toward the Earth to melt ice and illuminate the Earth during the day. To show how hot the sun is, the teacher can have the students construct an oven out of aluminum foil and place a hot dog in the foil on a very sunny day. The students can then have hot dogs cooked using the sun by reflecting the sun's rays on to the hot dog.
Death
Eventually, the star runs out of hydrogen, preventing it from producing enough thermal energy to resist gravity. When the sun finally runs out of fuel, it dies in a way dependent on how much mass it had when it formed. For example, stars with less than five solar masses turn into red giants, which release an envelope as a planetary nebula. After students have learned about the different phases of the sun, they can play a game of Pictionary with crayons. One student draws a certain type of star and the other students guess what the star's temperature would be. In another variation, one student describes the characteristics of the star and the other students name the star's temperature.