1 00:00:00,280 --> 00:00:04,450 [ Music ] 2 00:00:04,470 --> 00:00:08,620 [ Music ] Brunt: Fourteen days, 3 00:00:08,640 --> 00:00:12,710 two PistenBullies, four people, 4 00:00:12,730 --> 00:00:16,840 so yeah, 750 kilometers, door to door. 5 00:00:16,860 --> 00:00:21,130 [ wind blowing, music ] Brunt: Recently, we just got back from 6 00:00:21,150 --> 00:00:25,330 Antarctica where we completed about a two-week ground traverse 7 00:00:25,350 --> 00:00:29,560 near the South Pole. We were basically driving PistenBullies, 8 00:00:29,580 --> 00:00:33,660 tracked vehicles similar to the ones that groom your ski areas. 9 00:00:33,680 --> 00:00:37,810 Behind those PistenBullies were 60-foot long 10 00:00:37,830 --> 00:00:42,020 plastic sled trains. And ultimately those trains carried things like our sleeping tents, 11 00:00:42,040 --> 00:00:46,150 fully erected and left standing during the day when we were driving. 12 00:00:46,170 --> 00:00:50,300 Kitchen tent, fuel, generators, 13 00:00:50,320 --> 00:00:54,490 all sorts of cargo-- Neumann: Everything we needed for the trip. 14 00:00:54,510 --> 00:00:58,790 Brunt: And from a both science and survival standpoint. 15 00:00:58,810 --> 00:01:02,870 So this entire traverse was in support of ICESat-2, which will launch 16 00:01:02,890 --> 00:01:07,160 later in the year. Neumann: ICESat-2 is all about elevation, and 17 00:01:07,180 --> 00:01:11,230 the natural question is how you're getting the right answer? This is how we will know. We'll go 18 00:01:11,250 --> 00:01:15,310 out and collect a reference data. We'll be ready to compare and evaluate, see how we're doing. 19 00:01:15,330 --> 00:01:19,470 Radio: 3-1-9 is feeling kind of ready, how you guys doing over there? 20 00:01:19,490 --> 00:01:23,540 Neumann: So the big measurement we were making was to measure the elevation of the ice 21 00:01:23,560 --> 00:01:27,630 sheet surface around our traverse. And we had the two GPS running, one on each vehicle 22 00:01:27,650 --> 00:01:31,810 measuring that elevation. One of the other experiments we were doing is leaving out 23 00:01:31,830 --> 00:01:35,930 what we call corner cube reflectors to get an assessment of the pointing 24 00:01:35,950 --> 00:01:40,090 of ICESat-2. When we make an elevation measurement how are we sure it's in 25 00:01:40,110 --> 00:01:44,200 the right place. So in this picture you can see a bamboo pole with a little 26 00:01:44,220 --> 00:01:48,370 white cap on the end of it. And embedded in that cap, little piece of glass 27 00:01:48,390 --> 00:01:52,560 about as big as your pinky nail and calibrated to return 28 00:01:52,580 --> 00:01:56,760 green laser light from the satellite, bounces off of this thing 29 00:01:56,780 --> 00:02:00,850 and goes right back up to the satellite again. Super reflective. So these things, as 30 00:02:00,870 --> 00:02:04,990 Kelly has demonstrated, show up in data with altimeters 31 00:02:05,010 --> 00:02:09,240 like ICESat-2. When you first get to South Pole, and you're coming from 32 00:02:09,260 --> 00:02:13,310 McMurdo, which is a nice seaside town right at sea level, and South Pole is 33 00:02:13,330 --> 00:02:17,410 what, about 10,000 feet. And yeah, you notice it pretty quickly. The 34 00:02:17,430 --> 00:02:21,520 temperature is a lot colder than in McMurdo. It's probably 30 degrees 35 00:02:21,540 --> 00:02:25,700 40 degrees colder and 10,000 feet higher. Walking from the 36 00:02:25,720 --> 00:02:29,750 camp to where we're putting in an array for example, would be a ten minute walk maybe, 37 00:02:29,770 --> 00:02:33,870 five minutes. A couple of breaks on the way, you know, it's still pretty 38 00:02:33,890 --> 00:02:38,020 high. Brunt: The plan is to repeat this traverse for the 39 00:02:38,040 --> 00:02:42,210 next three years. So four years of data total, and that 40 00:02:42,230 --> 00:02:46,310 would last the mission lifetime--the mission requirement lifetime-- 41 00:02:46,330 --> 00:02:50,440 for ICESat-2. Neumann: ICESat-2 has 1,387 orbits 42 00:02:50,460 --> 00:02:54,630 and so it's cruising around the world, and it's got these unique tracks that repeat every 43 00:02:54,650 --> 00:02:58,850 91 days. And all those tracks converge at 88-South, and 44 00:02:58,870 --> 00:03:02,970 so our route crossed, what, twenty percent of them. So we can 45 00:03:02,990 --> 00:03:07,190 calibrate data from twenty percent of our tracks with this 46 00:03:07,210 --> 00:03:11,270 stretch that we drove. And by repeating it every year about the same time 47 00:03:11,290 --> 00:03:15,440 of year, we'll overlap it exactly the same time, but we'll also be able 48 00:03:15,460 --> 00:03:19,620 to figure out what's going on in between. Because we'll measure it in 2017, 49 00:03:19,640 --> 00:03:23,820 and then again in 2018, and you can see how it changes from year to year. So that will be pretty 50 00:03:23,840 --> 00:03:28,010 cool, too. It will quickly become the best-surveyed piece of 51 00:03:28,030 --> 00:03:32,080 either of the ice sheets. [ Music ] 52 00:03:32,100 --> 00:03:36,140 [ Music ] 53 00:03:36,160 --> 00:03:37,964 [ Music ]