1 00:00:00,000 --> 00:00:05,240 Hello everyone, I'm Steele McGonigal. 2 00:00:05,240 --> 00:00:06,440 And I'm Kara O'Brien. 3 00:00:06,440 --> 00:00:08,400 Welcome to Destination Tomorrow. 4 00:00:08,400 --> 00:00:12,520 This program will uncover how past, present and future research is creating today's knowledge 5 00:00:12,520 --> 00:00:15,600 to answer the questions and solve the challenges of tomorrow. 6 00:00:15,600 --> 00:00:20,080 The International Space Station orbits the Earth every 90 minutes and will provide an 7 00:00:20,080 --> 00:00:25,240 orbital laboratory in a reduced-gravity environment for long-term research. 8 00:00:25,240 --> 00:00:30,040 This microgravity environment gives researchers an opportunity to study the fundamental states 9 00:00:30,040 --> 00:00:34,280 of matter, solids, liquids and gases, and the forces that affect them. 10 00:00:34,280 --> 00:00:38,880 A unique facility at NASA Glenn is able to conduct microgravity research here on Earth. 11 00:00:38,880 --> 00:00:42,600 NASA researchers can study how the lack of gravity will affect the experiments before 12 00:00:42,600 --> 00:00:44,120 they are brought into space. 13 00:00:44,120 --> 00:00:52,280 Jennifer Pulley takes us inside NASA Glenn's 2.2-second drop tower. 14 00:00:52,320 --> 00:00:58,120 By now, you've all seen astronauts and objects floating around inside an orbiting spacecraft, 15 00:00:58,120 --> 00:01:01,280 seemingly free of Earth's gravitational field. 16 00:01:01,280 --> 00:01:03,280 But these images are misleading. 17 00:01:03,280 --> 00:01:09,000 In fact, these objects are actually not floating, but in a state of continuous freefall. 18 00:01:09,000 --> 00:01:15,040 Any object in freefall experiences microgravity, or weightlessness, which occurs when the object 19 00:01:15,040 --> 00:01:17,120 falls towards the Earth. 20 00:01:17,120 --> 00:01:21,360 Before NASA researchers send experiments on board shuttle missions or to the International 21 00:01:21,360 --> 00:01:24,280 Space Station, they often test them here on Earth. 22 00:01:24,280 --> 00:01:28,080 But how do you replicate microgravity here on Earth? 23 00:01:28,080 --> 00:01:33,400 NASA Glenn has been conducting microgravity experiments since the 1960s in drop towers 24 00:01:33,400 --> 00:01:34,960 like this. 25 00:01:34,960 --> 00:01:39,640 These facilities rely on freefall of the experiment to produce a microgravity environment. 26 00:01:39,640 --> 00:01:46,720 Here, NASA can test experiments in a reduced-gravity environment, similar to orbiting in space. 27 00:01:47,080 --> 00:01:52,480 The 2.2-second drop tower is one of two microgravity facilities here at the Glenn Research Center. 28 00:01:52,480 --> 00:01:55,160 This facility is just under 80 feet tall. 29 00:01:55,160 --> 00:01:59,520 We can drop experiments in this facility weighing up to 350 pounds. 30 00:01:59,520 --> 00:02:02,960 They'll reach a terminal velocity of almost 50 miles per hour just before they hit the 31 00:02:02,960 --> 00:02:04,760 airbag at the bottom of the tower. 32 00:02:04,760 --> 00:02:07,360 We create microgravity for 2.2 seconds here. 33 00:02:07,360 --> 00:02:08,360 You said microgravity. 34 00:02:08,360 --> 00:02:09,360 Do you mean weightlessness? 35 00:02:09,360 --> 00:02:12,520 Yes, that's exactly right. 36 00:02:12,520 --> 00:02:15,040 Microgravity is weightlessness. 37 00:02:15,040 --> 00:02:17,200 Astronauts experience that in orbit all the time. 38 00:02:17,200 --> 00:02:20,800 We need to create that down here on the Earth, and we can do that here in the 2.2-second 39 00:02:20,800 --> 00:02:24,760 drop tower. 40 00:02:24,760 --> 00:02:28,000 This is how a drop tower experiment works. 41 00:02:28,000 --> 00:02:33,720 Researchers place their experiments inside an aluminum frame, also called a rig. 42 00:02:33,720 --> 00:02:38,440 Experiment rigs are then placed inside a drag shield, but are not attached to it. 43 00:02:38,440 --> 00:02:45,880 Once assembled, the experiment package is lifted to the top of the tower, then released. 44 00:02:45,880 --> 00:02:53,480 When the experiment is dropped, it experiences microgravity, or zero-g, for 2.2 seconds. 45 00:02:53,480 --> 00:02:58,220 The drag shield protects the experiment from aerodynamic drag during the drop, which allows 46 00:02:58,220 --> 00:03:02,720 the experiment rig to fall freely a distance of 7.5 inches. 47 00:03:02,720 --> 00:03:08,040 The experiment experiences weightlessness, similar to what would be expected in space. 48 00:03:08,040 --> 00:03:11,160 During the drop tower, what happens is the experiment falls through the tower inside 49 00:03:11,160 --> 00:03:12,160 the drag shield. 50 00:03:12,160 --> 00:03:17,120 The drag shield is being slowed down by the aerodynamic drag as it approaches 50 miles 51 00:03:17,120 --> 00:03:19,800 an hour as it nears the bottom of the tower. 52 00:03:19,800 --> 00:03:25,040 The experiment inside, however, is falling through 7.5 inches inside the drag shield 53 00:03:25,040 --> 00:03:29,120 and is unaware of the aerodynamic drag that's occurring around it. 54 00:03:29,120 --> 00:03:31,680 There's three kinds of microgravity experiments we perform. 55 00:03:31,680 --> 00:03:34,280 Most of our work is centered on combustion. 56 00:03:34,280 --> 00:03:36,360 All the experiments are basically the same internally. 57 00:03:36,680 --> 00:03:40,800 There's a power system, there's a computer system on board to control the experiment 58 00:03:40,800 --> 00:03:45,080 as it falls through the tower, there's a diagnostic system on board, which takes the imaging or 59 00:03:45,080 --> 00:03:48,880 the pressure or temperature data from the experiment as it falls, and then there's the 60 00:03:48,880 --> 00:03:53,200 experiment itself, the thing that's actually burning or the liquid that's moving around 61 00:03:53,200 --> 00:03:54,200 inside the experiment. 62 00:03:54,200 --> 00:03:58,360 And we get all this ready, raise the experiment to the top of the tower that we have now, 63 00:03:58,360 --> 00:04:01,360 and we close it up, package it up, do a countdown. 64 00:04:02,360 --> 00:04:05,360 Three, two, one. 65 00:04:06,360 --> 00:04:09,360 And as the experiment falls through the tower, it's in microgravity. 66 00:04:09,360 --> 00:04:10,360 That's when the experiment runs. 67 00:04:10,360 --> 00:04:14,360 Why do we conduct microgravity experiments here on Earth when we can easily conduct them 68 00:04:14,360 --> 00:04:15,360 in space? 69 00:04:15,360 --> 00:04:18,360 Well, actually, to conduct them in space is quite expensive. 70 00:04:18,360 --> 00:04:23,360 The numbers I've heard is about $10,000 per pound just to lift the experiment into space. 71 00:04:23,360 --> 00:04:28,360 Not to mention the cost of having the astronaut operate the experiment while it's up there. 72 00:04:28,360 --> 00:04:31,360 Here in the drop tower, it's probably a bit less expensive to do that. 73 00:04:31,360 --> 00:04:35,360 And if we make a mistake, we can go back and run the experiment again quite rapidly. 74 00:04:35,360 --> 00:04:39,360 Our researchers set up the parameters for the experiments that do go up to space right 75 00:04:39,360 --> 00:04:41,360 here in the drop tower. 76 00:04:41,360 --> 00:04:46,360 So how do the combustion experiments that you conduct here at this facility in microgravity 77 00:04:46,360 --> 00:04:49,360 affect me, the general public? 78 00:04:49,360 --> 00:04:54,360 Well, the whole idea here is to understand combustion at the fundamental level. 79 00:04:55,360 --> 00:04:59,360 Once we understand that, we can go out and make cleaner burning engines, cleaner burning 80 00:04:59,360 --> 00:05:02,360 power plants, which means less pollution in the air. 81 00:05:02,360 --> 00:05:05,360 So we're less fuel-dependent and we have a cleaner environment. 82 00:05:05,360 --> 00:05:10,360 The 2.2-second drop tower was originally built in 1948 to house a distillation tower for 83 00:05:10,360 --> 00:05:11,360 making jet fuel. 84 00:05:11,360 --> 00:05:16,360 In the mid-1960s, the need to perform reduced gravity research in support of the space program 85 00:05:16,360 --> 00:05:18,360 saved the facility from being torn down. 86 00:05:18,360 --> 00:05:22,360 In the coming up, we'll see how playing video games can help us understand combustion 87 00:05:22,360 --> 00:05:26,360 We'll see how playing video games can help people overcome attention deficit hyperactivity disorder. 88 00:05:26,360 --> 00:05:31,360 But first, did you know NASA uses a specially adapted plane nicknamed the Vomit Comet that 89 00:05:31,360 --> 00:05:33,360 creates microgravity here on Earth? 90 00:05:33,360 --> 00:05:38,360 When the plane reaches the top of a parabolic trajectory, the occupants temporarily become 91 00:05:38,360 --> 00:05:41,360 weightless, experiencing what it is like to fly in space.