1 00:00:02,040 --> 00:00:06,680 Speaker 1: Welcome to brain stuff. From how stuff works. Hey, they 2 00:00:06,720 --> 00:00:09,959 Speaker 1: are brain stuff, Lauren Vogel bomb here. Mars has large 3 00:00:10,000 --> 00:00:13,880 Speaker 1: deposits of near pure water ice just beneath the surface 4 00:00:13,920 --> 00:00:17,360 Speaker 1: at mid latitudes, a discovery that could have huge implications 5 00:00:17,400 --> 00:00:21,239 Speaker 1: for future human settlement of the Red planet. Astronauts could 6 00:00:21,280 --> 00:00:23,360 Speaker 1: essentially just go there with a bucket and shovel and 7 00:00:23,360 --> 00:00:25,599 Speaker 1: get all the water they need, said Shane burn in 8 00:00:25,600 --> 00:00:29,320 Speaker 1: a press release from NASA's Jet Propulsion Laboratory. Burne, who 9 00:00:29,320 --> 00:00:32,440 Speaker 1: works at the University of Arizona Lunar and Planetary Laboratory 10 00:00:32,479 --> 00:00:35,280 Speaker 1: in Tucson, co authored a new study using the suite 11 00:00:35,280 --> 00:00:38,760 Speaker 1: of instruments and cameras on NASA's Mars Reconnaissance Orbiter or 12 00:00:39,120 --> 00:00:42,760 Speaker 1: m r O to uncover this icy find. Buried just 13 00:00:42,800 --> 00:00:45,400 Speaker 1: a few meters under the ground and covered by fused 14 00:00:45,520 --> 00:00:48,279 Speaker 1: rock and dust. These layers of ice were discovered at 15 00:00:48,320 --> 00:00:52,200 Speaker 1: eight sites in eroded scarps or steep hillsides. The most 16 00:00:52,280 --> 00:00:54,680 Speaker 1: exciting thing about these sites is that they're in regions 17 00:00:54,720 --> 00:00:58,400 Speaker 1: that could be accessible to future Mars explorers at to 18 00:00:58,480 --> 00:01:01,400 Speaker 1: fifty eight degrees latitude in the north, othern and southern hemisphere, 19 00:01:01,720 --> 00:01:05,080 Speaker 1: negating the need for traveling to challenging polar latitudes to 20 00:01:05,160 --> 00:01:08,840 Speaker 1: access a frozen water supply. These ice deposits come from 21 00:01:08,920 --> 00:01:12,160 Speaker 1: layers of ancient snow that became buried under rock and 22 00:01:12,360 --> 00:01:16,119 Speaker 1: more snow over time. These deposits have become exposed as 23 00:01:16,160 --> 00:01:19,200 Speaker 1: these scarps eroded. But how did layers of snow become 24 00:01:19,240 --> 00:01:22,760 Speaker 1: deposited at such low latitudes in the first place. Although 25 00:01:22,800 --> 00:01:25,560 Speaker 1: Mars currently exhibits ice and snow on the surface only 26 00:01:25,600 --> 00:01:29,760 Speaker 1: at high latitudes, this wasn't always the case. Mars experienced 27 00:01:29,760 --> 00:01:32,440 Speaker 1: shifts in its climate over the eons as its axis 28 00:01:32,440 --> 00:01:36,959 Speaker 1: of rotation changes. Its axial tilt currently approximates that of Earth's, 29 00:01:36,959 --> 00:01:39,000 Speaker 1: but over the course of hundreds of thousands, and even 30 00:01:39,080 --> 00:01:43,080 Speaker 1: millions of years, mars tilt has varied dramatically, driving global 31 00:01:43,120 --> 00:01:47,440 Speaker 1: climatic shifts. Scientists can therefore use the information recorded in 32 00:01:47,480 --> 00:01:50,720 Speaker 1: these scarps as an ancient geological record of how Mars's 33 00:01:50,720 --> 00:01:54,840 Speaker 1: climate has evolved. Leslie Tempari, m r O, Deputy project 34 00:01:54,840 --> 00:01:58,160 Speaker 1: scientist at NASA's Jet Propulsion Laboratory, told us, if you 35 00:01:58,200 --> 00:02:00,320 Speaker 1: had a mission at one of these sites, say umpling 36 00:02:00,320 --> 00:02:02,520 Speaker 1: the layers going down the scarp, you could get a 37 00:02:02,560 --> 00:02:05,720 Speaker 1: detailed climate history of Mars. It's part of the whole 38 00:02:05,760 --> 00:02:08,519 Speaker 1: story of what happens to water on Mars over time, 39 00:02:08,800 --> 00:02:11,480 Speaker 1: Where does it go, when does ice accumulate, when does 40 00:02:11,480 --> 00:02:14,240 Speaker 1: it recede. The study, which has been published in the 41 00:02:14,280 --> 00:02:17,280 Speaker 1: journal Science, is a real help to future human Mars 42 00:02:17,360 --> 00:02:20,240 Speaker 1: mission planners. To set up a viable human presence on 43 00:02:20,280 --> 00:02:23,960 Speaker 1: the Martian surface, astronauts will need to harness on site resources. 44 00:02:24,360 --> 00:02:28,320 Speaker 1: It would be wildly prohibitively expensive to bring all the water, fuel, 45 00:02:28,360 --> 00:02:31,520 Speaker 1: and building supplies with them from Earth. Tapping into a 46 00:02:31,520 --> 00:02:34,440 Speaker 1: plentiful supply of near pure water ice will be critical 47 00:02:34,480 --> 00:02:37,440 Speaker 1: for providing drinking water and a fuel resource, not to 48 00:02:37,440 --> 00:02:42,520 Speaker 1: mention irrigation for crops. Previously, scientists have confirmed large deposits 49 00:02:42,520 --> 00:02:46,200 Speaker 1: of subsurface water ice using ground penetrating radar, but the 50 00:02:46,240 --> 00:02:48,600 Speaker 1: information about what the ice is mixed with and the 51 00:02:48,720 --> 00:02:52,320 Speaker 1: quantity of water has been difficult to decipher. Now, by 52 00:02:52,320 --> 00:02:55,520 Speaker 1: studying these scarps, scientists have found that these deposits are 53 00:02:55,560 --> 00:02:59,160 Speaker 1: close to being pure water ice, and through observations by 54 00:02:59,240 --> 00:03:02,480 Speaker 1: orbiting space, we know where to send our astronauts too 55 00:03:02,520 --> 00:03:10,400 Speaker 1: big for water. Today's episode was written by Ian O'Neill 56 00:03:10,480 --> 00:03:13,200 Speaker 1: and produced by Tristan McNeil. For more on this and 57 00:03:13,400 --> 00:03:16,120 Speaker 1: lots of other cool topics, visit our home planet, how 58 00:03:16,160 --> 00:03:28,760 Speaker 1: stuff Works dot com.