1 00:00:00,000 --> 00:00:20,640 Hey kids! Remember Buzz Lightyear from Toy Story? Remember when he first met Woody and 2 00:00:20,640 --> 00:00:26,140 used his laser? Well, that laser was just a toy, but at NASA Langley Research Center 3 00:00:26,140 --> 00:00:31,620 in Hampton, Virginia, they use real lasers. You see, the lasers that are used at NASA 4 00:00:31,620 --> 00:00:36,660 study the Earth's atmosphere. In today's episode of NASA Connect, Van and I will take 5 00:00:36,660 --> 00:00:41,180 you to NASA Langley Research Center, where you'll meet scientists and researchers who 6 00:00:41,180 --> 00:00:47,100 use lasers and satellites to measure particles in the Earth's atmosphere. So stick around, 7 00:00:47,100 --> 00:00:52,100 as NASA Connect takes you on a trip to the upper reaches of the Earth's atmosphere. 8 00:00:52,100 --> 00:00:56,740 And remember guys, it's mathematics, science, and technology that make it all possible. 9 00:00:56,740 --> 00:01:03,740 Hang on, as NASA Connect takes you to infinity and beyond the Earth's atmosphere. 10 00:01:22,100 --> 00:01:29,100 And remember guys, it's mathematics, science, and technology that make it all possible. 11 00:01:52,100 --> 00:02:08,740 By the looks of it, your engine's in need of a serious tune-up. You need to replace 12 00:02:08,740 --> 00:02:14,220 your catalytic converter. Your van's sick, and it needs help. And you, young man, are 13 00:02:14,220 --> 00:02:21,220 contributing to global pollution. So, what does that mean? It means you're rejected. 14 00:02:22,100 --> 00:02:45,100 Is there anything else? No, thanks. Hey, stranger. Why the long face? Hey, Mr. Murphy 15 00:02:45,100 --> 00:02:50,260 rejected my van. He said that the particle emissions coming out of my van were too high 16 00:02:50,260 --> 00:02:55,580 and that I'm polluting the air. You're upset, huh? How does he even know my van's a polluter? 17 00:02:55,580 --> 00:03:00,340 So the van smokes a little. Big deal. I mean, how much can a little smoke damage do to the 18 00:03:00,340 --> 00:03:07,060 air? After all, it's only one van. Well, it is hard to understand how they measure what's 19 00:03:07,060 --> 00:03:12,220 in the smoke coming out of your van, because a lot of it we can't see. That's why garages 20 00:03:12,220 --> 00:03:16,500 that inspect vehicles have special tools to measure the amount of particle emissions in 21 00:03:16,500 --> 00:03:21,300 a car's exhaust. So, you see, Van, if your van's emission levels are too high, you get 22 00:03:21,300 --> 00:03:27,500 the big rejection. Well, how can you measure something you can't even see? Okay. Just because 23 00:03:27,500 --> 00:03:32,060 you can't see something doesn't mean it's not there, right? Take the air, for example. 24 00:03:32,060 --> 00:03:36,860 There are particles in the air right now that are so small, even our eyes can't see them. 25 00:03:36,860 --> 00:03:42,100 Believe me, those particles are there. Check it out. In the weather section of the newspaper, 26 00:03:42,100 --> 00:03:46,620 they report on something every day called the air quality index level. This level tells 27 00:03:46,620 --> 00:03:52,820 us the amount of particles, or aerosols, in the air around us. Aerosols? Like hairspray? 28 00:03:52,820 --> 00:03:59,140 Yeah. Simply put, an aerosol is a particle, either liquid or solid, that is suspended 29 00:03:59,140 --> 00:04:04,500 in the air. So, yes, hairspray is considered an aerosol. What are some other examples of 30 00:04:04,500 --> 00:04:10,180 aerosols? Chalk becomes an aerosol after you bang two erasers together. The flakes released 31 00:04:10,180 --> 00:04:15,220 into the air when you scratch your body become aerosols. Of course, the dust from desert 32 00:04:15,220 --> 00:04:21,060 storms and volcanic ash are also aerosols. Okay, so there are aerosols all around us, 33 00:04:21,060 --> 00:04:26,140 but we can't see them. But I'm still confused. How can we actually measure an aerosol? Look, 34 00:04:26,140 --> 00:04:30,620 why don't we take a road trip to Hampton, Virginia, and visit NASA Langley Research 35 00:04:30,620 --> 00:04:34,700 Center and Hampton University? I know some atmospheric scientists there who can help 36 00:04:34,700 --> 00:04:38,860 us both better understand how they measure aerosols in the atmosphere. Thank you. You're 37 00:04:38,860 --> 00:04:45,860 paying this. We always take my card. Hi, guys. Welcome to this episode of NASA Connect. 38 00:04:46,020 --> 00:04:51,540 I'm Jennifer Pulley. And I'm Van Hughes. Speaking about measuring aerosols, on today's show, 39 00:04:51,540 --> 00:04:57,540 NASA Connect travels to St. Stephen's Indian School on the Wind River Reservation in Wyoming. 40 00:04:57,540 --> 00:05:01,100 Students there will show you how to collect aerosols. You can conduct this experiment 41 00:05:01,100 --> 00:05:06,100 at your own school or even at home. And to help you understand the information in our 42 00:05:06,100 --> 00:05:09,940 program, every time our friend Norbert appears with a cue card, that's your cue to think 43 00:05:09,940 --> 00:05:15,060 about answers to the questions he gives you. Got it? You'll also meet NASA's Educational 44 00:05:15,060 --> 00:05:19,980 Technology Program Manager, Dr. Shelley Canright, who will introduce you to some students in 45 00:05:19,980 --> 00:05:26,500 California. Yeah, these kids are hooked up and turned on to our NASA Connect website. 46 00:05:26,500 --> 00:05:29,820 You'll see how they're using the Internet to learn more about measuring the Earth's 47 00:05:29,820 --> 00:05:34,980 atmosphere. For right now, let's get some expert help and some more background information 48 00:05:34,980 --> 00:05:40,540 on aerosols from Dr. M. Patrick McCormick. He's the co-director of Hampton University's 49 00:05:40,540 --> 00:05:47,540 Center for Atmospheric Sciences. How does the amount of aerosols in the atmosphere affect 50 00:05:50,020 --> 00:05:55,220 the Earth's weather condition? The atmosphere consists primarily of oxygen and other gases 51 00:05:55,220 --> 00:06:00,640 like nitrogen and water vapor, hydrogen. But did you know that the air we breathe also 52 00:06:00,680 --> 00:06:06,840 consists of tiny little particles called aerosols? Aerosols are very important for lots of reasons. 53 00:06:06,840 --> 00:06:12,240 For example, aerosols are thought to be important in climate by changing the properties of clouds. 54 00:06:12,240 --> 00:06:16,560 If you didn't have an aerosol, it would be very difficult for a cloud droplet to form. 55 00:06:16,560 --> 00:06:21,960 In the air, water molecules attach themselves to aerosols, and as they condense, a cloud 56 00:06:21,960 --> 00:06:28,320 droplet is formed. The aerosols act as seeds to start the formation of the cloud droplets. 57 00:06:28,320 --> 00:06:33,000 At any location, the amount of aerosols in the atmosphere can change how far we can see, 58 00:06:33,000 --> 00:06:38,880 the frequency of clouds in the sky, the thickness of clouds, and even the rainfall amount. Some 59 00:06:38,880 --> 00:06:44,480 aerosols are naturally occurring in the atmosphere, like sea salt, pollen, and particles produced 60 00:06:44,480 --> 00:06:50,720 by volcanic eruptions. Other aerosols are human-made, like factory pollutants, automobile 61 00:06:50,720 --> 00:06:57,520 exhaust, and smoke from biomass burning. Can aerosols affect the temperature here on Earth? 62 00:06:57,520 --> 00:07:02,720 Sure they can. When aerosols like smoke and dust and pollen float in the air, the air 63 00:07:02,720 --> 00:07:08,760 becomes hazy. Now, if this haziness reflects sunlight back to space, the effect is going 64 00:07:08,760 --> 00:07:13,320 to be a cooling of the atmosphere on Earth. But if this haziness absorbs energy, well, 65 00:07:13,320 --> 00:07:18,880 then the net effect is going to be a warming of the atmosphere here on Earth. 66 00:07:18,880 --> 00:07:23,160 After getting tons of information from Dr. McCormick, we drove to NASA Langley in Hampton, 67 00:07:23,160 --> 00:07:28,000 Virginia, to talk with Dr. Russell DeYoung, an atmospheric scientist in the chemistry 68 00:07:28,000 --> 00:07:29,480 and dynamics branch. 69 00:07:29,480 --> 00:07:31,000 Hi, I'm Van. 70 00:07:31,000 --> 00:07:33,840 Hi, glad to meet you. What brings you two here today? 71 00:07:33,840 --> 00:07:39,440 Well, it all started when Van's car failed inspection. It's because his emission levels 72 00:07:39,440 --> 00:07:40,440 were too high. 73 00:07:40,440 --> 00:07:44,040 Yeah, I can't believe I got rejected when there's so many other things in the atmosphere 74 00:07:44,040 --> 00:07:48,920 to worry about. Can my van's little emissions really affect the huge atmosphere above us? 75 00:07:49,240 --> 00:07:53,040 Okay, good. You've got a lot of good questions, and I think I can get some answers for you 76 00:07:53,040 --> 00:07:57,840 all. Here at NASA Langley in Hampton, Virginia, and NASA Goddard in Greenbelt, Maryland, we 77 00:07:57,840 --> 00:08:02,840 study how natural and man-made aerosols affect the atmosphere. You have one vehicle. Every 78 00:08:02,840 --> 00:08:07,160 family on your block has at least one vehicle. Your city is full of vehicles. In the U.S. 79 00:08:07,160 --> 00:08:12,040 alone, there are millions of vehicles, all burning fossil fuels. Altogether, these vehicles 80 00:08:12,040 --> 00:08:18,160 emit huge amounts of particles called aerosols that are carried long distances by the wind. 81 00:08:18,160 --> 00:08:24,040 Did you know that in 1991, Mount Pinatubo, a volcano in the Philippines, erupted, releasing 82 00:08:24,040 --> 00:08:29,400 massive aerosol concentrations into the air? These aerosols were immediately dispersed 83 00:08:29,400 --> 00:08:34,960 into the upper atmosphere. Three months later, these same aerosols could be found all over 84 00:08:34,960 --> 00:08:36,160 the Earth. 85 00:08:36,160 --> 00:08:42,560 Okay, your van is a small polluter. But think about this. Think about the combined effect 86 00:08:42,560 --> 00:08:47,160 of all the exhaust of all the cars in the world on the Earth's atmosphere. 87 00:08:47,160 --> 00:08:51,360 Wow, that's definitely something to think about. Hey, here's Norbert with some more 88 00:08:51,360 --> 00:08:53,160 questions for you to think about. 89 00:08:57,160 --> 00:08:59,160 How do aerosols affect our health? 90 00:08:59,160 --> 00:09:01,160 What is remote sensing? 91 00:09:01,160 --> 00:09:05,160 Name and describe the two types of remote sensing and give examples of each. 92 00:09:05,160 --> 00:09:08,160 How are aerosols in the atmosphere measured? 93 00:09:10,160 --> 00:09:15,160 Studying the atmosphere is a fairly new science. In the Chemistry and Dynamics Branch at NASA 94 00:09:15,160 --> 00:09:20,160 Langley Research Center, atmospheric scientists are trying to determine how many aerosols 95 00:09:20,160 --> 00:09:25,160 there are and where they are in the atmosphere. Now, these aerosols are important because 96 00:09:25,160 --> 00:09:31,160 they affect our health. Small aerosols can enter our lungs as we breathe polluted air. 97 00:09:31,160 --> 00:09:36,160 These aerosols can be deposited deep in our lungs, blocking the lungs' ability to exchange 98 00:09:36,160 --> 00:09:41,160 oxygen and carbon dioxide. Over time, this makes it hard to breathe. 99 00:09:42,160 --> 00:09:47,160 Here at NASA Langley, we measure aerosols using a technique called remote sensing. 100 00:09:47,160 --> 00:09:49,160 What is remote sensing? 101 00:09:49,160 --> 00:09:53,160 Remote sensing is collecting information about an object without physically touching the 102 00:09:53,160 --> 00:09:56,160 object. It's learning without touching. 103 00:09:56,160 --> 00:10:02,160 The most familiar kind of remote sensing is the use of our eyes to detect a distant object. 104 00:10:02,160 --> 00:10:08,160 We also learn without touching when we hear. For example, when a car beeps its horn, we 105 00:10:08,160 --> 00:10:11,160 hear it from a distance and sense we're in danger. 106 00:10:11,160 --> 00:10:13,160 Get out of the street! 107 00:10:13,160 --> 00:10:17,160 You know, there are two types of remote sensing, active and passive. 108 00:10:17,160 --> 00:10:23,160 An early example of passive remote sensing involved the use of a camera. In 1858, the 109 00:10:23,160 --> 00:10:28,160 first aerial photograph of land was taken from a balloon floating over Paris, France. 110 00:10:28,160 --> 00:10:33,160 This is called passive because the camera uses only the light from the sun to record 111 00:10:33,160 --> 00:10:35,160 the image on film. 112 00:10:35,160 --> 00:10:40,160 On the other hand, active remote sensing uses its own light source. 113 00:10:40,160 --> 00:10:44,160 Put a flash on the camera, and you've made it active because the light from the flash 114 00:10:44,160 --> 00:10:47,160 reflects off the distant object being photographed. 115 00:10:47,160 --> 00:10:51,160 Using active remote sensing, you can take pictures whenever you want because you don't 116 00:10:51,160 --> 00:10:54,160 have to depend on the sun to give you light. 117 00:10:55,160 --> 00:11:01,160 Explain how scientists use LIDAR to help them measure the aerosols in the atmosphere. 118 00:11:01,160 --> 00:11:06,160 Here in our lab at NASA Langley, we use a technique called active remote sensing. 119 00:11:06,160 --> 00:11:10,160 Now that means that we carry our own light source. We don't wait around for the sun to 120 00:11:10,160 --> 00:11:16,160 shine on the object. And we use, what we do is we use short pulses of laser light to probe 121 00:11:16,160 --> 00:11:19,160 the atmosphere. This technique is called LIDAR. 122 00:11:19,160 --> 00:11:22,160 LIDAR stands for light detection and ranging. 123 00:11:22,160 --> 00:11:27,160 A LIDAR uses short pulses of laser light to detect aerosols in the atmosphere. 124 00:11:27,160 --> 00:11:33,160 NASA Langley is involved in active remote sensing from the ground and in the air. 125 00:11:33,160 --> 00:11:40,160 At NASA Ames in California, LIDAR is flown in a high-altitude ER-2 aircraft to record 126 00:11:40,160 --> 00:11:47,160 atmospheric data. And at NASA Dryden, also in California, a high-altitude ER-2 aircraft 127 00:11:47,160 --> 00:11:53,160 is being developed that can stay aloft for weeks, even months, at a time to make atmospheric 128 00:11:53,160 --> 00:11:54,160 measurements. 129 00:11:54,160 --> 00:11:56,160 So how does LIDAR work? 130 00:11:56,160 --> 00:12:04,160 Well, first of all, we open this trap door and then align our LIDAR under the open sky. 131 00:12:04,160 --> 00:12:11,160 Then we shoot a pulsed laser beam into the atmosphere. Some of that laser beam scatters 132 00:12:12,160 --> 00:12:18,160 off the tiny aerosol particles and scatters light into this telescope. The light is then 133 00:12:18,160 --> 00:12:20,160 captured by this detector. 134 00:12:20,160 --> 00:12:25,160 By precisely timing the laser pulse going out into the atmosphere and the reflected 135 00:12:25,160 --> 00:12:31,160 light coming back to the telescope, scientists can accurately measure the location and number 136 00:12:31,160 --> 00:12:32,160 of aerosols. 137 00:12:32,160 --> 00:12:37,160 Now remember, this is active remote sensing, much like that flash on the camera. 138 00:12:37,160 --> 00:12:43,160 Okay, I understand passive and active remote sensing and how LIDAR works, but how do you 139 00:12:43,160 --> 00:12:47,160 measure the distance from the ground to the aerosols in the atmosphere? You can't use 140 00:12:47,160 --> 00:12:48,160 a meter stick. 141 00:12:48,160 --> 00:12:56,160 Okay, let's say you wanted to measure something far away, say like aerosols in the sky. You're 142 00:12:56,160 --> 00:12:59,160 right, you wouldn't use a meter stick. 143 00:12:59,160 --> 00:13:02,160 Scientists at NASA Langley use mathematics. 144 00:13:02,160 --> 00:13:09,160 A pulse of laser light is shot from point A. The beam travels from point A to the aerosols 145 00:13:09,160 --> 00:13:16,160 at point B. Then the light reflects off the aerosols and bounces back to point A. If you 146 00:13:16,160 --> 00:13:21,160 know how fast it takes for a pulse of laser light to travel and you know a little math, 147 00:13:21,160 --> 00:13:24,160 then you can calculate how far away it is. 148 00:13:25,160 --> 00:13:27,160 What is a nanosecond? 149 00:13:27,160 --> 00:13:31,160 A nanosecond is one billionth of a second, basically. 150 00:13:39,160 --> 00:13:42,160 It's a really small amount of time. 151 00:13:42,160 --> 00:13:47,160 Okay, let's say you wanted to measure the distance from the ground to the aerosols in 152 00:13:47,160 --> 00:13:48,160 the atmosphere. 153 00:13:48,160 --> 00:13:50,160 You can't use a meter stick. 154 00:13:51,160 --> 00:13:54,160 It's a really small amount of time. 155 00:13:54,160 --> 00:14:03,160 Anyway, if a scientist shoots a pulse of laser light at the sky and that beam reflects back, 156 00:14:05,160 --> 00:14:18,160 say in 6,000 nanoseconds, the aerosols in the sky are really 3,000 nanoseconds away. 157 00:14:18,160 --> 00:14:19,160 Why? 158 00:14:19,160 --> 00:14:26,160 Because you have to divide the total time by 2 in order to find the time one way. 159 00:14:26,160 --> 00:14:27,160 Got it? 160 00:14:27,160 --> 00:14:33,160 So, if you multiply the time one way, 3,000 nanoseconds, by the number of meters in a 161 00:14:33,160 --> 00:14:38,160 nanosecond, one third, you get 1,000 meters. 162 00:14:38,160 --> 00:14:42,160 If you know how to convert meters to kilometers, you can calculate that the aerosols in the 163 00:14:42,160 --> 00:14:45,160 sky are one kilometer away. 164 00:14:46,160 --> 00:14:48,160 Well, that should answer your question, Van. 165 00:14:48,160 --> 00:14:53,160 But you know, in order to get the whole picture, we need to measure aerosols from space. 166 00:14:53,160 --> 00:14:56,160 Let me call a few colleagues of mine over at Hampton University who are working with 167 00:14:56,160 --> 00:15:01,160 NASA Langley Ball Aerospace and the French Space Agency to get them to explain to you 168 00:15:01,160 --> 00:15:04,160 how we can measure aerosols from space. 169 00:15:04,160 --> 00:15:09,160 Well, while Dr. DeYoung makes his arrangements, let's travel to the Wind River Reservation 170 00:15:09,160 --> 00:15:14,160 in Wyoming where students at St. Stephen's Indian School are being atmospheric detectives. 171 00:15:15,160 --> 00:15:18,160 Welcome to St. Stephen's Indian School! 172 00:15:18,160 --> 00:15:25,160 St. Stephen's Indian School is a BIA grant school situated on the Wind River Indian Reservation 173 00:15:25,160 --> 00:15:27,160 in central Wyoming. 174 00:15:27,160 --> 00:15:32,160 The reservation is home to nearly 10,000 Native Americans, mostly of the Northern Arapaho 175 00:15:32,160 --> 00:15:34,160 and Shoshone tribes. 176 00:15:34,160 --> 00:15:38,160 Students work hard on the usual subjects like math and English. 177 00:15:38,160 --> 00:15:42,160 We are very proud to be involved in this project. 178 00:15:42,160 --> 00:15:44,160 Soccer! 179 00:15:44,160 --> 00:15:49,160 NASA Connect asked us to show you how to do the lesson for this show. 180 00:15:49,160 --> 00:15:52,160 Here's how you can become real atmospheric detectives. 181 00:15:52,160 --> 00:15:57,160 Once you've gathered the materials listed in the educator's guide, locate a specific 182 00:15:57,160 --> 00:16:01,160 outside area that is flat, elevated, and open. 183 00:16:01,160 --> 00:16:04,160 Divide the class into four research groups. 184 00:16:04,160 --> 00:16:09,160 Each group then tapes one piece of contact paper to the center of the cardboard. 185 00:16:09,160 --> 00:16:14,160 Tape the one piece of contact paper in the center of the cardboard with the sticky side up. 186 00:16:14,160 --> 00:16:17,160 Keep the protective backing on the contact paper. 187 00:16:17,160 --> 00:16:23,160 Repeat the above procedure for a total of two aerosol samplers for each research group. 188 00:16:23,160 --> 00:16:29,160 Each group is then assigned an area on the school grounds in which to place its sampler. 189 00:16:29,160 --> 00:16:34,160 Each group completes the morning column on Table A, Observations of Weather Conditions, 190 00:16:34,160 --> 00:16:37,160 on Student Data Worksheet Number 1. 191 00:16:37,160 --> 00:16:41,160 You'll need to refer to the local paper, watch the local weather report, 192 00:16:41,160 --> 00:16:47,160 or visit www.weather.com before completing your observations. 193 00:16:47,160 --> 00:16:52,160 Now place one of the samplers on a flat surface, preferably a meter or two above the ground. 194 00:16:52,160 --> 00:16:55,160 Remove the protective backing from the contact paper. 195 00:16:55,160 --> 00:16:59,160 After exposing the sampler to the outside air for at least two hours, 196 00:16:59,160 --> 00:17:04,160 place the aerosol sampler grid, grid side down, over the contact paper 197 00:17:04,160 --> 00:17:07,160 and return the sampler to the classroom. 198 00:17:07,160 --> 00:17:12,160 Using a magnifying glass or holding the contact paper up to a light, 199 00:17:12,160 --> 00:17:18,160 count the number of aerosols found in each of ten randomly selected squares on the grid. 200 00:17:18,160 --> 00:17:22,160 Randomly select the squares by tossing the dice twice. 201 00:17:22,160 --> 00:17:26,160 Record the number of aerosols in each sample square on Table B, 202 00:17:26,160 --> 00:17:31,160 Aerosol Sampler Collection Data, on Student Data Worksheet Number 1. 203 00:17:31,160 --> 00:17:36,160 Add up all the aerosols in the ten randomly selected squares to get a total. 204 00:17:36,160 --> 00:17:45,160 Next, divide the total number of aerosols by ten to get an average, or mean, of the aerosols per square. 205 00:17:45,160 --> 00:17:48,160 Repeat the procedure for the afternoon samples. 206 00:17:48,160 --> 00:17:54,160 After the average number of aerosols per square for each of the two samplers has been calculated, 207 00:17:54,160 --> 00:17:59,160 construct a line graph using the aerosol sampler line graph to compare the data. 208 00:18:00,160 --> 00:18:05,160 After you've completed this activity at school, you'll take your own sampler home. 209 00:18:05,160 --> 00:18:09,160 Place your sampler on a flat surface one to two meters above the ground. 210 00:18:09,160 --> 00:18:12,160 Leave your sampler outside overnight. 211 00:18:12,160 --> 00:18:18,160 First thing in the morning, attach the aerosol sampler grid, grid side down, to the contact paper. 212 00:18:18,160 --> 00:18:20,160 Bring your sampler to school with you. 213 00:18:20,160 --> 00:18:25,160 When you get to school, your teachers will give you time to randomly select your ten squares. 214 00:18:25,160 --> 00:18:32,160 Find the average and record the data in Table C aerosol sampler data, collection from home, on Student Data Worksheet Number 2. 215 00:18:34,160 --> 00:18:39,160 Next, you'll write your address and the total number of aerosols from Table C on a self-adhesive note. 216 00:18:39,160 --> 00:18:47,160 Your teacher will divide a map of your community into four regions, northeast, northwest, southeast, and southwest. 217 00:18:47,160 --> 00:18:51,160 All students will place their labeled adhesive notes onto the map where they live. 218 00:18:51,160 --> 00:18:57,160 Using the data from the map, find the average for each region and make a class graph of the data. 219 00:18:58,160 --> 00:19:00,160 Analyze your data, guys! 220 00:19:00,160 --> 00:19:05,160 Now that you have the results from your sampler, you should review the data and discuss your observations. 221 00:19:05,160 --> 00:19:07,160 Then, consider these questions. 222 00:19:08,160 --> 00:19:12,160 How can weather conditions affect the results of this activity? 223 00:19:13,160 --> 00:19:19,160 What are some other methods you could use to collect data on aerosols in the atmosphere? 224 00:19:20,160 --> 00:19:24,160 Look at your map of your community and the data collected from home. 225 00:19:24,160 --> 00:19:29,160 What is the relationship between where students live and the amount of aerosols collected? 226 00:19:30,160 --> 00:19:33,160 Teachers, check out our NASA Connect website. 227 00:19:33,160 --> 00:19:40,160 From here, you can download the Educator's Guide, where you'll find more questions like these that will help your students analyze their data. 228 00:19:40,160 --> 00:19:44,160 Now, let's head back to Hampton University and meet Dr. John Anderson. 229 00:19:45,160 --> 00:19:51,160 Dr. Anderson uses space-based passive remote sensing to measure aerosols in the atmosphere. 230 00:19:51,160 --> 00:19:58,160 Remember, this type of remote sensing is different from LIDAR, which uses active remote sensing to measure aerosols. 231 00:19:58,160 --> 00:20:05,160 Dr. Anderson's passive remote sensing system is actually above us right now, on a satellite in space. 232 00:20:05,160 --> 00:20:09,160 A satellite is any object that orbits another object in space. 233 00:20:15,160 --> 00:20:18,160 Compare and contrast SAGE II with PICASSO SINA. 234 00:20:19,160 --> 00:20:25,160 How will PICASSO SINA help scientists measure aerosols more accurately? 235 00:20:30,160 --> 00:20:31,160 Dr. Anderson? 236 00:20:31,160 --> 00:20:32,160 Hi, Jennifer. 237 00:20:32,160 --> 00:20:33,160 Hi, Van. 238 00:20:33,160 --> 00:20:37,160 Dr. DeYoung told me you guys were coming over to learn how a satellite instrument measures aerosols. 239 00:20:37,160 --> 00:20:41,160 Yeah, actually, he thought you could help us out on information about satellite systems. 240 00:20:41,160 --> 00:20:42,160 I'd be glad to help. 241 00:20:42,160 --> 00:20:47,160 I'm involved with a satellite instrument called SAGE II, which stands for Stratospheric Aerosol and Gas Experiment. 242 00:20:48,160 --> 00:20:54,160 The less sunlight that gets through the atmosphere at specific wavelengths, the higher density of aerosols there are in the atmosphere. 243 00:20:54,160 --> 00:21:01,160 A way to demonstrate what the SAGE II photometer might see up in space is to hit two erasers together and shine a light through the dust. 244 00:21:01,160 --> 00:21:05,160 This light from the flashlight represents the light from the sun. 245 00:21:05,160 --> 00:21:11,160 Researchers look at the reduction of the sun's light to measure how many aerosols there are between the sun and the satellite. 246 00:21:11,160 --> 00:21:14,160 Remember, SAGE II only uses light from the sun. 247 00:21:15,160 --> 00:21:19,160 You know, Van, when I was a student in college, I had to actually collect samples from a real cloud. 248 00:21:19,160 --> 00:21:20,160 Really? 249 00:21:20,160 --> 00:21:21,160 Oh, yeah. 250 00:21:21,160 --> 00:21:25,160 I would climb Mount Mitchell, North Carolina, when the clouds would collect around the mountain. 251 00:21:25,160 --> 00:21:30,160 Droplets would form on a Teflon string collector I would hold up and would run down into a container. 252 00:21:30,160 --> 00:21:36,160 It demonstrates the same principle which applies when water vapor is attracted to an aerosol in the atmosphere to create drops in clouds. 253 00:21:36,160 --> 00:21:37,160 Cool. 254 00:21:37,160 --> 00:21:40,160 Say, how would you like to learn about the Picasso-Sena system? 255 00:21:40,160 --> 00:21:41,160 Okay. 256 00:21:41,160 --> 00:21:45,160 Picasso-Sena, like SAGE II, will be a satellite-borne instrument that measures aerosols. 257 00:21:45,160 --> 00:21:54,160 But it is quite different than SAGE II in that Picasso-Sena uses active remote sensing, while SAGE II uses passive remote sensing. 258 00:21:54,160 --> 00:22:06,160 My colleague, Dr. Ali Omar, is developing the Picasso-Sena system along with Hampton University, NASA Langley Research Center, Ball Aerospace, and the French Space Agency, CNES. 259 00:22:06,160 --> 00:22:09,160 Why don't I send both of you over to see him right now? 260 00:22:09,160 --> 00:22:10,160 That would be great. 261 00:22:10,160 --> 00:22:14,160 While Van and I head over to meet Dr. Omar, why don't you meet Dr. Shelley Canright? 262 00:22:14,160 --> 00:22:17,160 She's got a special NASA connection to the web just for you. 263 00:22:18,160 --> 00:22:25,160 NASA Earth science researchers routinely use technology in conducting experiments and analyzing and communicating the results. 264 00:22:25,160 --> 00:22:34,160 Matter of fact, these researchers are much like a detective, collecting evidence and investigating a range of suspects that might be contributing to the situation. 265 00:22:34,160 --> 00:22:41,160 I'd like to introduce everyone to a class of online atmospheric detectives at East Palo Alto Charter School in East Palo Alto, California. 266 00:22:41,160 --> 00:22:46,160 They've taken on a case that Langley Learning Technologies Project has posted on the NASA Connect website. 267 00:22:46,160 --> 00:22:48,160 Let's check in on them. 268 00:22:48,160 --> 00:22:55,160 We've been asked by NASA to investigate two puzzling situations related to remote sensing. 269 00:22:55,160 --> 00:23:06,160 After doing a background check on remote sensing and checking out the application of remote sensing by bats and satellites, we felt prepared for the NASA Connect web challenge. 270 00:23:06,160 --> 00:23:14,160 In the first puzzle, Satellite Sight, we have been challenged to identify facts about the mystery image that you see on your screen. 271 00:23:14,160 --> 00:23:21,160 The questions where, what, and why help guide us through an interpretation of the image. 272 00:23:21,160 --> 00:23:27,160 Hey, now I can name each geographical feature in the satellite's image based on its color. 273 00:23:27,160 --> 00:23:28,160 You can do it too. 274 00:23:28,160 --> 00:23:36,160 Just visit Norman's lab on the NASA Connect website and find the atmospheric detectives online activity button. 275 00:23:36,160 --> 00:23:48,160 The completion of the first puzzle prepared us for the detailed attention we would have to give to figure out the second half of the remote sensing puzzle. 276 00:23:49,160 --> 00:24:00,160 In the next activity, atmospheric aerosols, we're trying to figure out the density or concentration of aerosols over two different regions of the Earth. 277 00:24:00,160 --> 00:24:14,160 We're using information such as relative density, altitude, distance, and latitude and longitude to interpret data about the image just like scientists do. 278 00:24:14,160 --> 00:24:20,160 Well, Jennifer, it sounds like the case being worked by the East Palo Alto Charter School students could use some more sleuths. 279 00:24:20,160 --> 00:24:26,160 I would encourage our viewers to visit the NASA Connect website to take a crack at these remote sensing puzzles. 280 00:24:26,160 --> 00:24:28,160 Thanks a lot, Shelley. 281 00:24:28,160 --> 00:24:32,160 Hey, while you guys got connected to the web, Van and I met up with Dr. Ali Omar. 282 00:24:32,160 --> 00:24:35,160 He's a scientist who studies the atmosphere using satellites. 283 00:24:35,160 --> 00:24:40,160 And hopefully, he'll be able to convince Van of the importance of keeping his car emissions low. 284 00:24:40,160 --> 00:24:41,160 Thanks, Jennifer. 285 00:24:41,160 --> 00:24:42,160 Thanks, Jennifer. 286 00:24:42,160 --> 00:24:48,160 First of all, let me welcome you to Hampton University's computer lab where some of our students are studying atmospheric science. 287 00:24:48,160 --> 00:24:54,160 So, Dr. Omar, how does PICASSO SENA measure aerosols in the atmosphere? 288 00:24:54,160 --> 00:25:05,160 Well, Van, of all the aerosol measuring systems you have seen, LIDAR, SAGE II, and the aerosol sampler used by students at St. Stephen's School have their uses. 289 00:25:05,160 --> 00:25:07,160 But they also have their limitations. 290 00:25:08,160 --> 00:25:15,160 PICASSO SENA is being developed for launch in 2003 to give us a more complete picture of our atmosphere. 291 00:25:15,160 --> 00:25:23,160 The PICASSO SENA mission will greatly improve our understanding of the nature and magnitude of radiative effects of aerosols and clouds. 292 00:25:23,160 --> 00:25:29,160 There are many uncertainties as to whether a cloud heats or cools the Earth's surface. 293 00:25:29,160 --> 00:25:35,160 This is due to inadequate knowledge of how cloud layers are distributed within the atmosphere. 294 00:25:35,160 --> 00:25:41,160 PICASSO SENA will help us obtain more complete observations of cloud distributions and properties. 295 00:25:41,160 --> 00:25:46,160 PICASSO SENA will also use LIDAR in combination with an instrument called a spectrometer. 296 00:25:46,160 --> 00:25:53,160 The spectrometer is a percive remote sensing instrument that measures the radiance of scattered sunlight. 297 00:25:53,160 --> 00:26:02,160 Using both LIDAR and spectrometer observations will provide us with a more accurate measure of aerosol and cloud properties than either technique alone. 298 00:26:02,160 --> 00:26:05,160 Changes in climate are inevitable. 299 00:26:05,160 --> 00:26:12,160 But the rapid pace of change that may be starting to take place presents a potential threat to our planet. 300 00:26:12,160 --> 00:26:20,160 The new knowledge from PICASSO SENA will improve our ability to make accurate predictions about these changes. 301 00:26:20,160 --> 00:26:25,160 Predictions to help world leaders define policies that affect us all. 302 00:26:25,160 --> 00:26:31,160 So you see Van, a little bit of emissions from your car combined with all the other emissions affect us all. 303 00:26:31,160 --> 00:26:33,160 We know the world's population is growing. 304 00:26:33,160 --> 00:26:37,160 There are certain things we need to do now in order to protect our environment. 305 00:26:37,160 --> 00:26:40,160 One of those things is getting your catalytic converter fixed. 306 00:26:40,160 --> 00:26:44,160 Okay. Well, thank you very much, Dr. Omar, for all your help. 307 00:26:44,160 --> 00:26:45,160 Thanks a lot, Dr. Omar. 308 00:26:45,160 --> 00:26:46,160 You're welcome. 309 00:26:46,160 --> 00:26:49,160 Well, we'd like to thank everyone who helped out with today's show, 310 00:26:49,160 --> 00:26:56,160 especially all the students who were in the program, the NASA researchers, Hampton University, and of course, Dr. Shelley Canright. 311 00:26:56,160 --> 00:27:01,160 If you would like a videotaped copy of this NASA Connect show and the Educator's Guide lesson plans, 312 00:27:01,160 --> 00:27:06,160 contact CORE, the NASA central operation of resources for educators. 313 00:27:06,160 --> 00:27:10,160 All this information and more is located on the NASA Connect website. 314 00:27:10,160 --> 00:27:15,160 So, for Van and the rest of the NASA Connect crew, I'm Jennifer Pulley. 315 00:27:15,160 --> 00:27:17,160 So, Van, what are you going to do? 316 00:27:17,160 --> 00:27:23,160 You know, Mr. Murphy, it's important to have your car running right and clean. 317 00:27:23,160 --> 00:27:27,160 Not only is it healthy for breathing, but it's also good for the environment. 318 00:27:27,160 --> 00:27:30,160 Hey, is that your car out there? 319 00:27:30,160 --> 00:27:32,160 Kind of a clunker, wouldn't you say? 320 00:27:32,160 --> 00:27:33,160 Huh? 321 00:27:33,160 --> 00:27:38,160 You ought to get that inspected and fixed and clean. 322 00:27:38,160 --> 00:27:42,160 Did you know that the atmosphere contains aerosols? 323 00:27:42,160 --> 00:27:46,160 An aerosol is a particle suspended in the air, and aerosols help to form clouds. 324 00:27:46,160 --> 00:27:51,160 Some clouds bring rain, but some clouds trap the sun's rays, bringing global warming. 325 00:27:52,160 --> 00:27:56,160 But all clouds reflect the light, which can cause global cooling. 326 00:27:56,160 --> 00:27:59,160 It all has to do with particles becoming aerosols. 327 00:27:59,160 --> 00:28:04,160 Say, you know, there might be particles coming off this tailpipe right now. 328 00:28:04,160 --> 00:28:07,160 See? More soot into the atmosphere. 329 00:28:07,160 --> 00:28:08,160 We ought to fix this. 330 00:28:08,160 --> 00:28:11,160 Maybe I can move it. 331 00:28:11,160 --> 00:28:12,160 Oops. 332 00:28:12,160 --> 00:28:14,160 Sorry, Mr. Murphy. 333 00:28:14,160 --> 00:28:16,160 Maybe you should clean up. 334 00:28:21,160 --> 00:28:25,160 Thank you for watching.