1 00:00:03,376 --> 00:00:08,040 ? [music] ? 2 00:00:11,226 --> 00:00:14,671 KIDS: Our World! 3 00:00:14,673 --> 00:00:18,083 EVAN: Hold on Globey, just one more cut should do it. 4 00:00:18,085 --> 00:00:22,738 Here we go... and Ta Dah!!! 5 00:00:22,740 --> 00:00:25,758 It’s a snowflake!! Snowflakes are a beautiful part of our 6 00:00:25,760 --> 00:00:28,670 world and they also very fascinating. 7 00:00:28,671 --> 00:00:32,498 One place that’s no stranger to snow is Lake Placid, New York. 8 00:00:32,500 --> 00:00:36,068 Once a year NASA Goddard Space Flight Center co hosts a 9 00:00:36,070 --> 00:00:39,205 program called the History of Winter. It’s there that 10 00:00:39,206 --> 00:00:41,306 students and teachers can study... 11 00:00:41,308 --> 00:00:44,710 You guessed it, snow! Let’s visit some experts there and 12 00:00:44,711 --> 00:00:47,013 find out why NASA has such an interest in the 13 00:00:47,015 --> 00:00:49,348 science of snow. TIM MCCOLLUM: The idea was that 14 00:00:49,350 --> 00:00:54,086 the students would become engaged in scientific research. 15 00:00:54,088 --> 00:00:56,588 It wouldn’t be a word problem in a book. It would be 16 00:00:56,590 --> 00:00:59,058 something that they could literally be outside looking at 17 00:00:59,060 --> 00:01:01,293 something that they could analyze. Something they could 18 00:01:01,295 --> 00:01:03,530 study. They’d have to dress, they’d have to prepare for the 19 00:01:03,531 --> 00:01:08,066 elements. When students look at a snowflake, because of what 20 00:01:08,068 --> 00:01:11,436 they’ve learned and what we’ve learned about the structure and 21 00:01:11,438 --> 00:01:14,073 everything that goes into forming a snowflake as it’s 22 00:01:14,141 --> 00:01:17,071 falling from the sky and the different changes that it goes 23 00:01:17,140 --> 00:01:19,745 through. That a snowflake represents a history of what 24 00:01:19,813 --> 00:01:22,315 happened to that snowflake on the way down. 25 00:01:22,316 --> 00:01:25,318 EVAN: So if I stare at a snowflake and find out exactly 26 00:01:25,320 --> 00:01:28,621 what it’s been through, you could call me a snow detective! 27 00:01:28,623 --> 00:01:31,891 But what causes snow and where does it come from? 28 00:01:31,893 --> 00:01:34,960 TIM: Snow is not rain that freezes on the way down. 29 00:01:34,961 --> 00:01:38,163 That’s how we end up with sleet. Snow is basically 30 00:01:38,165 --> 00:01:41,701 something that forms directly from water vapor in the air. 31 00:01:41,703 --> 00:01:43,836 PETE WASILEWSKI: The cloud conditions first of all have to 32 00:01:43,838 --> 00:01:46,973 be cold enough and then you need a little bit of 33 00:01:46,975 --> 00:01:52,345 dust to nucleate a little tiny ice crystal. 34 00:01:52,346 --> 00:01:56,783 TIM: Then as those snowflakes fall, as they pass through 35 00:01:56,785 --> 00:01:59,385 different layers of temperature, and different 36 00:01:59,386 --> 00:02:02,188 percentages of humidity, and as the wind blows them around and 37 00:02:02,190 --> 00:02:04,356 as they bump into other snowflakes on their way down- 38 00:02:04,358 --> 00:02:07,860 all of those factors go into the actual shape and you wind 39 00:02:07,861 --> 00:02:10,496 up getting more of these star like pattern that we’re 40 00:02:10,498 --> 00:02:13,766 familiar with. Looking at a snowflake really does tell so 41 00:02:13,768 --> 00:02:16,601 much about its history as it’s falling. 42 00:02:16,603 --> 00:02:19,405 EVAN: So if no two snowflakes are alike, then what are the 43 00:02:19,406 --> 00:02:22,541 different types of snowflakes? TIM: That is what the students 44 00:02:22,543 --> 00:02:25,111 are most interested in. And they see there is such a wide 45 00:02:25,113 --> 00:02:28,146 variety. Most snowflakes, or many snowflakes don’t look at 46 00:02:28,148 --> 00:02:32,085 all like what most people think in terms of a snowflake. 47 00:02:32,086 --> 00:02:35,455 Some of them look like bullets. They literally have a pointy 48 00:02:35,456 --> 00:02:38,323 end. And when you walk into a driving snowstorm, and it’s 49 00:02:38,325 --> 00:02:41,160 hitting your face and it kind of stings and you look at the 50 00:02:41,161 --> 00:02:43,763 shape of those crystals, well that makes sense. Or they’ll 51 00:02:43,765 --> 00:02:47,200 look like hourglasses, we call hollow columns. Or capped 52 00:02:47,201 --> 00:02:50,503 columns which almost look like spools of thread. And there’s 53 00:02:50,505 --> 00:02:55,275 such a wide variety, but they’re still all ice crystals. 54 00:02:55,276 --> 00:02:58,076 EVAN: At the “History of Winter” event, teachers and 55 00:02:58,078 --> 00:03:01,013 students look at the shape of snowflakes then record the 56 00:03:01,015 --> 00:03:04,050 weather conditions. They’re building a huge database of 57 00:03:04,051 --> 00:03:07,335 crystals and weather conditions to discover connections. 58 00:03:07,336 --> 00:03:09,921 But why do all this research? 59 00:03:09,923 --> 00:03:13,225 TIM: As much as we’ve learned about the Earth’s system and 60 00:03:13,226 --> 00:03:16,796 what a complex system it is, the more we realize there’s so 61 00:03:16,798 --> 00:03:20,233 much we don’t’ know. And as we learn more about something as 62 00:03:20,235 --> 00:03:23,168 simple as a snowflake, and the conditions it takes to form a 63 00:03:23,170 --> 00:03:26,205 snowflake, it helps all of us have a better understanding of 64 00:03:26,206 --> 00:03:30,076 the way the atmosphere works. Hopefully we will learn more 65 00:03:30,078 --> 00:03:34,065 about the conditions that change our climate. 66 00:03:34,066 --> 00:03:37,283 EVAN: Who knew you could learn so much from something as small 67 00:03:37,285 --> 00:03:40,386 as a snowflake? I think I’m going outside and be a snow 68 00:03:40,388 --> 00:03:43,623 detective too. Come on Globey! 69 00:03:43,625 --> 00:03:47,260 You can be a snow detective too, just go to the History of 70 00:03:47,261 --> 00:03:50,833 Winter website and download the forms. 71 00:03:53,341 --> 00:03:57,441 ? [music] ? 72 00:04:02,466 --> 00:04:06,755 KIDS: Our World!