1 00:00:00,000 --> 00:00:15,880 Hi, I'm Christy Carlson Romano. 2 00:00:15,880 --> 00:00:20,000 I play Wren Stevens on Disney Channel's Even Stevens, and I'm the voice of Kim Possible. 3 00:00:20,000 --> 00:00:24,480 You know, the wonder teen who saves the world, does her homework, and updates her wardrobe 4 00:00:24,480 --> 00:00:25,920 all on a school night? 5 00:00:25,920 --> 00:00:26,920 Yeah. 6 00:00:26,920 --> 00:00:30,640 And she uses math, science, and technology to fight off evil villains. 7 00:00:30,640 --> 00:00:34,920 But seriously, I have some really cool friends who find these subjects helpful in solving 8 00:00:34,920 --> 00:00:35,920 real problems. 9 00:00:35,920 --> 00:00:40,480 They are the Treehouse Detectives, and you can meet them on NASA Sci-Files. 10 00:00:40,480 --> 00:00:43,640 They're going to be traveling to places that we can only dream of going. 11 00:00:43,640 --> 00:00:49,680 So, join in the adventure, and help the Treehouse Detectives solve their newest case. 12 00:00:50,680 --> 00:00:59,680 Come on now, and learn about math, science, and technology. 13 00:00:59,680 --> 00:01:05,680 NASA Sci-Files. 14 00:01:05,680 --> 00:01:09,680 Discovering the world we're in. 15 00:01:09,680 --> 00:01:13,680 Doing cool experiments. 16 00:01:13,680 --> 00:01:20,680 NASA Sci-Files. 17 00:01:20,680 --> 00:01:27,680 NASA Sci-Files. 18 00:01:27,680 --> 00:01:31,680 Don't forget to look for the answers to the following questions. 19 00:01:31,680 --> 00:01:35,680 Why is it important to find water ice on Mars? 20 00:01:35,680 --> 00:01:41,680 How will the Phoenix Mars Lander analyze soil and water ice on Mars? 21 00:01:41,680 --> 00:01:44,680 What is ferrofluid, and why did NASA develop it? 22 00:01:44,680 --> 00:01:48,680 When you see this icon, the answer is near. 23 00:02:11,680 --> 00:02:32,680 So, uh, good job, Bianca. 24 00:02:32,680 --> 00:02:36,680 Next time I think we need to slow down a bit, because I don't want you to pull a muscle 25 00:02:36,680 --> 00:02:37,680 or anything. 26 00:02:37,680 --> 00:02:41,680 Actually, I was thinking about picking up the pace a little. 27 00:02:41,680 --> 00:02:44,680 Me too, but let's think about this realistically. 28 00:02:44,680 --> 00:02:47,680 We still have a few years before we have to take the physical test to be astronauts, 29 00:02:47,680 --> 00:02:50,680 and I think we should take it easy, you know at first. 30 00:02:50,680 --> 00:02:55,680 RJ, we're talking about possibly being the first astronauts to travel to Mars. 31 00:02:55,680 --> 00:02:58,680 I think I'll go ahead and run home. 32 00:02:58,680 --> 00:03:01,680 That's two miles. Have you considered speed walking? 33 00:03:01,680 --> 00:03:04,680 It's okay, I'm expecting a letter. 34 00:03:04,680 --> 00:03:13,680 I think I'll just shoot for going to the moon. 35 00:03:13,680 --> 00:03:15,680 Hi, RJ. 36 00:03:15,680 --> 00:03:17,680 Are you okay? 37 00:03:17,680 --> 00:03:19,680 You look awful. 38 00:03:19,680 --> 00:03:20,680 Tony! 39 00:03:20,680 --> 00:03:23,680 I mean, awfully fit. 40 00:03:23,680 --> 00:03:26,680 Bianca's killing me. I can't hide it any longer. 41 00:03:26,680 --> 00:03:29,680 I mean, I'm running twice a day just to keep up with her. 42 00:03:29,680 --> 00:03:31,680 Why the sudden interest in physical fitness? 43 00:03:31,680 --> 00:03:33,680 Remember what Mr. Gregory said? 44 00:03:33,680 --> 00:03:36,680 We could actually be the first astronauts to go to Mars. 45 00:03:36,680 --> 00:03:39,680 And you have to be in great shape to be an astronaut. 46 00:03:39,680 --> 00:03:41,680 Yes, and in the case of the biological biosphere, 47 00:03:41,680 --> 00:03:44,680 Miss Shepherd told us about how astronauts have to train to stay in shape, 48 00:03:44,680 --> 00:03:46,680 both on Earth and in space. 49 00:03:46,680 --> 00:03:48,680 We also learned that you can overdo it. 50 00:03:48,680 --> 00:03:51,680 Getting in shape shouldn't mean you have to run yourself into the ground. 51 00:03:51,680 --> 00:03:54,680 Maybe that's why NASA has manned and unmanned missions. 52 00:03:54,680 --> 00:03:56,680 Did you say manned and unmanned? 53 00:03:56,680 --> 00:03:59,680 Sure, with the way my fitness training is going, 54 00:03:59,680 --> 00:04:02,680 maybe I need to think about working on an unmanned mission. 55 00:04:02,680 --> 00:04:04,680 Good idea. Not that you're not in shape, 56 00:04:04,680 --> 00:04:08,680 but Mr. Gregory did say that NASA not only needs future astronauts, 57 00:04:08,680 --> 00:04:11,680 but also researchers, engineers, and scientists. 58 00:04:11,680 --> 00:04:12,680 And GFPs. 59 00:04:12,680 --> 00:04:14,680 What's a GFP? 60 00:04:14,680 --> 00:04:17,680 Galactic Financial Planners. 61 00:04:17,680 --> 00:04:19,680 Come on, guys, get with the program. 62 00:04:19,680 --> 00:04:21,680 Actually, Tony has an interesting point. 63 00:04:21,680 --> 00:04:24,680 I'm sure there's lots of ways to get involved with space exploration. 64 00:04:24,680 --> 00:04:27,680 Yes, NASA needs lots of people in all kinds of careers. 65 00:04:27,680 --> 00:04:29,680 We just need to find one we like. 66 00:04:29,680 --> 00:04:31,680 Let's bring up the problem board. 67 00:04:32,680 --> 00:04:34,680 What do we know? 68 00:04:34,680 --> 00:04:38,680 We know that there are both manned and unmanned missions to explore space. 69 00:04:38,680 --> 00:04:41,680 Exactly, and we also know that there are missions 70 00:04:41,680 --> 00:04:43,680 that involve going to the Moon, Mars, and beyond. 71 00:04:43,680 --> 00:04:47,680 We also know that NASA needs space explorers and scientists. 72 00:04:47,680 --> 00:04:49,680 Okay, so what do we need to know? 73 00:04:49,680 --> 00:04:51,680 We need to learn more about unmanned missions 74 00:04:51,680 --> 00:04:53,680 and what it takes to be an astronaut. 75 00:04:53,680 --> 00:04:54,680 I'll check out the NASA website. 76 00:04:54,680 --> 00:04:56,680 The NASA website is the perfect place to find out about 77 00:04:56,680 --> 00:05:00,680 future NASA missions and space exploration, along with careers. 78 00:05:00,680 --> 00:05:02,680 Perhaps I can do something in R&D. 79 00:05:02,680 --> 00:05:03,680 R&D? 80 00:05:03,680 --> 00:05:05,680 Research and Development. 81 00:05:05,680 --> 00:05:08,680 Because, as you know, I'm a big fan of research. 82 00:05:08,680 --> 00:05:10,680 Well, this may be right up your alley, RJ. 83 00:05:10,680 --> 00:05:11,680 What is it? 84 00:05:11,680 --> 00:05:13,680 I've contacted Dr. Carol Stoker. 85 00:05:13,680 --> 00:05:15,680 She's working on the latest NASA Mars mission. 86 00:05:15,680 --> 00:05:18,680 It's a lander called the Phoenix that the University of Arizona 87 00:05:18,680 --> 00:05:20,680 and the NASA Ames Research Center are developing. 88 00:05:20,680 --> 00:05:24,680 Isn't Kaylee in San Francisco doing some research on redwood trees? 89 00:05:24,680 --> 00:05:26,680 Yes. She doesn't get back until next week. 90 00:05:26,680 --> 00:05:29,680 I'll send her an email to see if she can talk to Dr. Stoker. 91 00:05:29,680 --> 00:05:32,680 Great. Maybe we should talk to Dr. D, too. 92 00:05:32,680 --> 00:05:34,680 Maybe he'll have some ideas about manned space travel. 93 00:05:34,680 --> 00:05:37,680 Actually, I was supposed to meet Dr. D at the Virginia Air and Space Center 94 00:05:37,680 --> 00:05:39,680 to check out a new exhibit on strange matter. 95 00:05:39,680 --> 00:05:40,680 I better run. 96 00:05:42,680 --> 00:05:45,680 We're very excited about the new vision for NASA, 97 00:05:45,680 --> 00:05:48,680 space exploration, and the Phoenix lander. 98 00:05:48,680 --> 00:05:51,680 But we are just wondering why we want to explore Mars 99 00:05:51,680 --> 00:05:53,680 instead of some of the other planets. 100 00:05:55,680 --> 00:05:58,680 Well, Mars is the planet in our solar system most like Earth, 101 00:05:58,680 --> 00:06:00,680 and it also may be another home for life. 102 00:06:00,680 --> 00:06:01,680 What do you mean? 103 00:06:01,680 --> 00:06:04,680 Well, some scientists think that life may have evolved on Mars early in its history 104 00:06:04,680 --> 00:06:07,680 when it was warmer and wetter than it is today. 105 00:06:07,680 --> 00:06:11,680 But the exciting thing would be if life still exists on Mars now. 106 00:06:11,680 --> 00:06:13,680 That's very exciting. 107 00:06:13,680 --> 00:06:17,680 So why don't we check it out instead of sending unmanned missions to Mars? 108 00:06:17,680 --> 00:06:19,680 Well, robotic missions cost less, 109 00:06:19,680 --> 00:06:21,680 and they help us learn a lot about the surface of Mars. 110 00:06:21,680 --> 00:06:23,680 The more we know about Mars, 111 00:06:23,680 --> 00:06:26,680 the more information we have to help design more effective human missions. 112 00:06:26,680 --> 00:06:27,680 That makes sense. 113 00:06:27,680 --> 00:06:29,680 So where will the Phoenix lander explore? 114 00:06:29,680 --> 00:06:32,680 The Phoenix will land in Mars' northern Arctic plains, 115 00:06:32,680 --> 00:06:34,680 between 65 and 75 degrees north. 116 00:06:34,680 --> 00:06:36,680 Why is it landing there? 117 00:06:36,680 --> 00:06:40,680 The landing site was chosen because another mission to Mars, 118 00:06:40,680 --> 00:06:45,680 called the Mars Odyssey, has discovered near-subsurface water ice. 119 00:06:45,680 --> 00:06:49,680 That's water ice that's under a layer of dry soil that's fairly thin, 120 00:06:49,680 --> 00:06:50,680 right in that location. 121 00:06:50,680 --> 00:06:52,680 Why is water ice so important? 122 00:06:52,680 --> 00:06:56,680 Well, the simple answer is that water is the most important ingredient for life, 123 00:06:56,680 --> 00:06:58,680 but it must be liquid water. 124 00:06:58,680 --> 00:07:00,680 On Earth, wherever we find liquid water, we find life. 125 00:07:00,680 --> 00:07:02,680 But isn't ice the solid form of water? 126 00:07:02,680 --> 00:07:05,680 Yes, but recent climate studies and climate modeling 127 00:07:05,680 --> 00:07:08,680 indicate that ice at the surface or near the subsurface 128 00:07:08,680 --> 00:07:11,680 in the area where Phoenix is landing may melt from time to time 129 00:07:11,680 --> 00:07:13,680 under some circumstances. 130 00:07:13,680 --> 00:07:15,680 Melted ice means liquid water. 131 00:07:15,680 --> 00:07:16,680 That's correct. 132 00:07:16,680 --> 00:07:20,680 And when water's liquid, microbial life could be growing in the soil 133 00:07:20,680 --> 00:07:23,680 and then become dormant when conditions get harsh. 134 00:07:23,680 --> 00:07:26,680 I learned at camp that when a plant or animal is dormant, it's inactive, 135 00:07:26,680 --> 00:07:28,680 sort of like sleeping. 136 00:07:28,680 --> 00:07:31,680 It's not actively growing, but it's protected by the environment 137 00:07:31,680 --> 00:07:34,680 until conditions are favorable for it to grow. 138 00:07:34,680 --> 00:07:38,680 That's right, and on Mars, we hope to find that when conditions become favorable, 139 00:07:38,680 --> 00:07:42,680 the ice melts and organisms wake up and grow. 140 00:07:42,680 --> 00:07:44,680 How do we know if there are microbes in the soil? 141 00:07:44,680 --> 00:07:48,680 Well, Phoenix won't be able to actually detect microbes in the soil, 142 00:07:48,680 --> 00:07:52,680 but it will be able to determine if the environment was ever habitable, 143 00:07:52,680 --> 00:07:56,680 and it may detect things left by biology in the past, 144 00:07:56,680 --> 00:07:59,680 such as organic compounds and other clues. 145 00:07:59,680 --> 00:08:02,680 But how will it be able to analyze the soil and water ice? 146 00:08:02,680 --> 00:08:06,680 There's a robotic arm with a digging tool designed to dig into the subsurface 147 00:08:06,680 --> 00:08:09,680 and scratch and obtain samples of the soil and ice. 148 00:08:09,680 --> 00:08:12,680 The samples will then be placed into instruments that will analyze the samples 149 00:08:12,680 --> 00:08:15,680 for such things as the type of minerals in the soil, 150 00:08:15,680 --> 00:08:19,680 any organic compounds, the chemical properties, and much more. 151 00:08:19,680 --> 00:08:22,680 The data will help us determine if the environment would be a good one for life. 152 00:08:22,680 --> 00:08:26,680 That sounds so exciting. I can't wait until the Phoenix lands on Mars. 153 00:08:26,680 --> 00:08:29,680 Well, it doesn't launch until 2007, but in the meantime, 154 00:08:29,680 --> 00:08:32,680 there's lots of exciting things going on at NASA to hold your interest. 155 00:08:32,680 --> 00:08:34,680 Thank you so much, Dr. Stoker. 156 00:08:34,680 --> 00:08:37,680 You're welcome. Don't hesitate to call if you have any more questions. 157 00:08:37,680 --> 00:08:52,680 ♪ music ♪ 158 00:08:52,680 --> 00:08:55,680 Hi, Tony. This strange matter exhibit is really cool, 159 00:08:55,680 --> 00:08:58,680 and it's a great place to learn about manned missions to space. 160 00:08:58,680 --> 00:09:00,680 Strange matter? I don't see the connection. 161 00:09:00,680 --> 00:09:04,680 Space is a very harsh environment, and for people to explore space, 162 00:09:04,680 --> 00:09:07,680 we have to overcome such problems as meteoroids and other space debris 163 00:09:07,680 --> 00:09:09,680 colliding with the spacecraft. 164 00:09:09,680 --> 00:09:12,680 I never thought of that. I guess it could be very dangerous. 165 00:09:12,680 --> 00:09:14,680 So, uh, what can we do? 166 00:09:14,680 --> 00:09:16,680 Couldn't you shatter the glass with a bowling ball? 167 00:09:16,680 --> 00:09:18,680 Because it is specially tempered glass. 168 00:09:18,680 --> 00:09:19,680 Thankfully. 169 00:09:19,680 --> 00:09:24,680 ♪ music ♪ 170 00:09:24,680 --> 00:09:28,680 Space is really important to have materials that don't shatter upon impact. 171 00:09:28,680 --> 00:09:30,680 The International Space Station, for example, 172 00:09:30,680 --> 00:09:33,680 has layers of Kevlar that prevent micrometeorites from penetrating. 173 00:09:33,680 --> 00:09:36,680 Isn't that the same stuff they use for bulletproof vests? 174 00:09:36,680 --> 00:09:39,680 That's right. I've got a Kevlar glove right here. Check it out. 175 00:09:39,680 --> 00:09:43,680 ♪ music ♪ 176 00:09:43,680 --> 00:09:45,680 Wow, that must be a really tall blade. 177 00:09:45,680 --> 00:09:47,680 Let's see how this works on an ordinary glove. 178 00:09:47,680 --> 00:09:55,680 ♪ music ♪ 179 00:09:55,680 --> 00:09:56,680 I'll take the Kevlar glove. 180 00:09:56,680 --> 00:09:58,680 Good choice. 181 00:09:58,680 --> 00:10:01,680 Now, what else about space is harsh? 182 00:10:01,680 --> 00:10:04,680 Well, I would think it's extremely cold in space. 183 00:10:04,680 --> 00:10:05,680 Yes, it is. 184 00:10:05,680 --> 00:10:08,680 Insulation to protect from extreme heat and cold is critical, 185 00:10:08,680 --> 00:10:10,680 like the display on soap foams. 186 00:10:10,680 --> 00:10:11,680 That's pretty impressive. 187 00:10:11,680 --> 00:10:13,680 What does that have to do with insulation? 188 00:10:13,680 --> 00:10:14,680 Let me show you. 189 00:10:14,680 --> 00:10:16,680 Here, take this piece of aerogel. 190 00:10:16,680 --> 00:10:19,680 It's sometimes called frozen smoke. 191 00:10:19,680 --> 00:10:22,680 It's the world's lightest solid, which means it's the least dense. 192 00:10:22,680 --> 00:10:24,680 You're right. It weighs a lot less than I thought it would. 193 00:10:24,680 --> 00:10:28,680 A piece the size of a human body would have a mass of less than half a kilogram, 194 00:10:28,680 --> 00:10:29,680 or about a pound. 195 00:10:29,680 --> 00:10:33,680 It's mostly air, about 99.8%. 196 00:10:33,680 --> 00:10:35,680 Oh, I see. It's like the soap bubbles. They're mostly air. 197 00:10:35,680 --> 00:10:38,680 It turns out that air does a great job of insulation, 198 00:10:38,680 --> 00:10:42,680 either keeping heat out or preventing heat from leaving. 199 00:10:42,680 --> 00:10:45,680 Let me show you. 200 00:10:45,680 --> 00:10:49,680 Here, hold this balloon on the opposite side of the aerogel from the microtorch. 201 00:10:50,680 --> 00:10:53,680 Now move the balloon up. 202 00:10:56,680 --> 00:10:58,680 That torch looks mighty hot, 203 00:10:58,680 --> 00:11:01,680 but nothing happened to the balloon as long as the aerogel was right there. 204 00:11:01,680 --> 00:11:04,680 Try touching the aerogel. Is it hot? 205 00:11:04,680 --> 00:11:07,680 No, not at all. 206 00:11:10,680 --> 00:11:13,680 Aerogel was used to insulate the Mars rover Sojourner 207 00:11:13,680 --> 00:11:16,680 from intense swings in the Martian temperature. 208 00:11:16,680 --> 00:11:19,680 NASA is experimenting with aerogel now 209 00:11:19,680 --> 00:11:23,680 to see if it can be made more transparent and used as a window. 210 00:11:23,680 --> 00:11:26,680 What about radiation in space? Isn't that a difficult problem? 211 00:11:26,680 --> 00:11:29,680 That's right. Astronauts need protection from radiation. 212 00:11:29,680 --> 00:11:33,680 The atmosphere and the Earth's magnetic field protect us from these things. 213 00:11:33,680 --> 00:11:37,680 On a journey to Mars, for example, it's especially important to have shielding. 214 00:11:37,680 --> 00:11:40,680 So will they use lead? I've heard that it stops a lot of radiation. 215 00:11:40,680 --> 00:11:43,680 It does, but it's way too heavy to haul into space. 216 00:11:43,680 --> 00:11:46,680 And it has some other problems. So what's the solution? 217 00:11:46,680 --> 00:11:49,680 Well, NASA is experimenting with a lot of different ideas. 218 00:11:49,680 --> 00:11:52,680 But one of them involves this. 219 00:11:52,680 --> 00:11:55,680 Dr. G, you've got to be kidding. 220 00:11:55,680 --> 00:11:58,680 That's a grocery bag. 221 00:11:58,680 --> 00:12:01,680 It's called polyethylene plastic. 222 00:12:01,680 --> 00:12:04,680 Of course it would have to be thicker than this. 223 00:12:04,680 --> 00:12:07,680 Another possibility is liquid hydrogen. 224 00:12:07,680 --> 00:12:10,680 Now, let's talk about ferrofluids. 225 00:12:10,680 --> 00:12:13,680 Ferrofluids? 226 00:12:13,680 --> 00:12:16,680 NASA first developed ferrofluids to deal with the flow of liquid fuel 227 00:12:16,680 --> 00:12:19,680 and the weightlessness of space. 228 00:12:19,680 --> 00:12:22,680 It has magnetic material suspended in the liquid, 229 00:12:22,680 --> 00:12:25,680 so it can be controlled by magnets. 230 00:12:25,680 --> 00:12:28,680 I didn't realize how harsh it is in space. 231 00:12:28,680 --> 00:12:31,680 I think we really need to learn more about how space travel affects the human body. 232 00:12:31,680 --> 00:12:34,680 Why don't you contact Dr. Schaffner at NASA Johnson Space Center in Houston? 233 00:12:34,680 --> 00:12:37,680 That would be a big help. Thanks, Dr. D. 234 00:12:37,680 --> 00:12:40,680 By the way, I hear that Bianca is going to space camp. 235 00:12:40,680 --> 00:12:43,680 I'm sure she'll also learn a lot about being an astronaut.