1 00:00:00,050 --> 00:00:10,070 Music 2 00:00:10,090 --> 00:00:12,090 3 00:00:12,110 --> 00:00:16,110 Narrator: This is a very simple activity that models the supernova explosion 4 00:00:16,130 --> 00:00:20,120 that takes place at the end of a large star's life. 5 00:00:20,140 --> 00:00:24,140 The only supplies you will need are two balls of different sizes for each person 6 00:00:24,160 --> 00:00:28,150 that is participating. A tennis ball and a ping pong ball are perfect for this. 7 00:00:28,170 --> 00:00:32,190 If we drop just the tennis ball, it bounces a foot or two. 8 00:00:32,210 --> 00:00:34,230 9 00:00:34,250 --> 00:00:38,290 If we drop just the ping pong ball in the same way, it again 10 00:00:38,310 --> 00:00:42,330 bounces, but not as high. When we drop them both together, 11 00:00:42,350 --> 00:00:46,380 with the ping pong ball stacked on top of the tennis ball, the ping pong ball 12 00:00:46,400 --> 00:00:50,400 goes flying off even further, and the tennis ball basically stays where it is. 13 00:00:50,420 --> 00:00:54,420 The reason this happens is that when the tennis ball hits the 14 00:00:54,440 --> 00:00:58,460 floor, its energy is transferred to the ping pong ball. 15 00:00:58,480 --> 00:01:02,480 In this model, the balls represent layers of the star's 16 00:01:02,500 --> 00:01:06,480 atmosphere that are falling inward during its implosion. These falling 17 00:01:06,500 --> 00:01:10,500 layers meet the energy from the iron core- represented by the floor in our activity- 18 00:01:10,520 --> 00:01:14,520 and rebound, shooting off into space in a dramatic supernova explosion. 19 00:01:14,540 --> 00:01:32,706 Music