WEBVTT FILE 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