1 00:00:08,549 --> 00:00:05,910 good afternoon and welcome to nasa 2 00:00:10,709 --> 00:00:08,559 headquarters in washington d.c i'm steve 3 00:00:12,709 --> 00:00:10,719 cole from the office of communications 4 00:00:15,589 --> 00:00:12,719 we're here today to bring you the latest 5 00:00:16,790 --> 00:00:15,599 findings in nasa's ongoing exploration 6 00:00:18,390 --> 00:00:16,800 of mars 7 00:00:20,870 --> 00:00:18,400 we have been following the water on the 8 00:00:23,189 --> 00:00:20,880 red planet for some time now today's 9 00:00:25,429 --> 00:00:23,199 announcement is going to add a new and 10 00:00:28,150 --> 00:00:25,439 exciting chapter to that voyage of 11 00:00:31,429 --> 00:00:28,160 scientific discovery the new results are 12 00:00:33,430 --> 00:00:31,439 based on observations from nasa's mars 13 00:00:35,910 --> 00:00:33,440 reconnaissance orbiter 14 00:00:38,389 --> 00:00:35,920 today we have five experts from 15 00:00:40,069 --> 00:00:38,399 five mars experts to tell you more about 16 00:00:42,869 --> 00:00:40,079 this new finding 17 00:00:44,950 --> 00:00:42,879 the first speaker will be michael meyer 18 00:00:46,790 --> 00:00:44,960 who is the lead scientist for the mars 19 00:00:48,470 --> 00:00:46,800 exploration program here at nasa 20 00:00:50,389 --> 00:00:48,480 headquarters 21 00:00:52,950 --> 00:00:50,399 alfred mcewen from the university of 22 00:00:55,670 --> 00:00:52,960 arizona who is the lead author of the 23 00:00:57,670 --> 00:00:55,680 paper being published today in science 24 00:01:00,310 --> 00:00:57,680 and principal investigator of the 25 00:01:02,069 --> 00:01:00,320 high-rise instrument on the orbiter the 26 00:01:04,149 --> 00:01:02,079 high-resolution imaging science 27 00:01:06,870 --> 00:01:04,159 experiment 28 00:01:08,870 --> 00:01:06,880 our third speaker is colin dundas also a 29 00:01:11,350 --> 00:01:08,880 co-author on the science paper a 30 00:01:13,109 --> 00:01:11,360 research geologist from the u.s 31 00:01:15,590 --> 00:01:13,119 geological survey 32 00:01:17,350 --> 00:01:15,600 in flagstaff arizona 33 00:01:20,310 --> 00:01:17,360 providing a broader perspective on the 34 00:01:22,550 --> 00:01:20,320 new findings will be philip christensen 35 00:01:23,830 --> 00:01:22,560 a geophysicist from arizona state 36 00:01:25,510 --> 00:01:23,840 university 37 00:01:29,030 --> 00:01:25,520 and lisa pratt 38 00:01:31,030 --> 00:01:29,040 a bio geochemist from indiana university 39 00:01:33,190 --> 00:01:31,040 after our panelist presentations we'll 40 00:01:36,149 --> 00:01:33,200 take questions from the press here in 41 00:01:38,310 --> 00:01:36,159 the auditorium and on the phone lines 42 00:01:41,190 --> 00:01:38,320 so now we can begin our first speaker 43 00:01:43,270 --> 00:01:41,200 michael meyer michael thank you steve 44 00:01:45,510 --> 00:01:43,280 the mars exploration program has a 45 00:01:47,670 --> 00:01:45,520 long-term strategy implemented through 46 00:01:50,469 --> 00:01:47,680 orbiters and landers to determine the 47 00:01:51,990 --> 00:01:50,479 planet's potential for life past present 48 00:01:53,590 --> 00:01:52,000 or future 49 00:01:56,310 --> 00:01:53,600 and along this line 50 00:01:58,630 --> 00:01:56,320 we followed the overarching theme of 51 00:02:01,350 --> 00:01:58,640 follow the water because water plays a 52 00:02:02,709 --> 00:02:01,360 major role in geological processes and 53 00:02:05,190 --> 00:02:02,719 climate 54 00:02:07,510 --> 00:02:05,200 in future human exploration and in the 55 00:02:09,430 --> 00:02:07,520 potential for life 56 00:02:11,750 --> 00:02:09,440 what we found on earth is if there's 57 00:02:13,110 --> 00:02:11,760 life there's if there's water there's 58 00:02:15,510 --> 00:02:13,120 life 59 00:02:17,030 --> 00:02:15,520 and this is true for mars 60 00:02:18,869 --> 00:02:17,040 the marsh reconnaissance orbiter has 61 00:02:22,869 --> 00:02:18,879 been a critical piece in our long-term 62 00:02:24,790 --> 00:02:22,879 strategy launched in august of 2005 is 63 00:02:26,630 --> 00:02:24,800 been in the work in orbit around mars 64 00:02:27,670 --> 00:02:26,640 since 2006 65 00:02:30,550 --> 00:02:27,680 and has 66 00:02:32,470 --> 00:02:30,560 imaged the planet in high spectral and 67 00:02:34,550 --> 00:02:32,480 spatial resolution 68 00:02:37,990 --> 00:02:34,560 in its extended mission has already 69 00:02:41,910 --> 00:02:38,000 collected an unprecedented 17.5 70 00:02:47,110 --> 00:02:44,390 and it is really pointed away to future 71 00:02:48,550 --> 00:02:47,120 landing sites it served as a relay for 72 00:02:51,430 --> 00:02:48,560 landed assets 73 00:02:53,750 --> 00:02:51,440 and also as image given a spectacular 74 00:02:57,670 --> 00:02:53,760 images of the red planet 75 00:02:59,110 --> 00:02:57,680 and mro and the program have found water 76 00:03:01,350 --> 00:02:59,120 in the form of 77 00:03:04,390 --> 00:03:01,360 ancient banks on rivers 78 00:03:06,949 --> 00:03:04,400 shorelines of long gone lakes 79 00:03:10,309 --> 00:03:06,959 minerals that form in water 80 00:03:12,710 --> 00:03:10,319 abundant water ice and polar areas 81 00:03:16,630 --> 00:03:12,720 near surface ice in the mid latitudes 82 00:03:17,430 --> 00:03:16,640 exposed in fresh like fresh craters 83 00:03:19,589 --> 00:03:17,440 and 84 00:03:24,789 --> 00:03:19,599 all very promising 85 00:03:28,630 --> 00:03:26,869 today we're going to hear about one of 86 00:03:32,309 --> 00:03:28,640 the benefits of having a long-term 87 00:03:34,470 --> 00:03:32,319 program catching mars and the act we 88 00:03:36,949 --> 00:03:34,480 have followed the water 89 00:03:38,470 --> 00:03:36,959 and we have found 90 00:03:40,630 --> 00:03:38,480 repeated 91 00:03:42,710 --> 00:03:40,640 and predictable evidence suggesting 92 00:03:44,470 --> 00:03:42,720 water flowing on mars 93 00:03:46,309 --> 00:03:44,480 and to tell us more about that i'm 94 00:03:48,470 --> 00:03:46,319 turning to the principal investigator of 95 00:03:49,990 --> 00:03:48,480 highrise alfred mcewen 96 00:03:51,430 --> 00:03:50,000 thank you michael 97 00:03:53,509 --> 00:03:51,440 so we have been 98 00:03:56,390 --> 00:03:53,519 observing mars with highrise for two and 99 00:03:57,830 --> 00:03:56,400 a half mars years now and one of our 100 00:04:00,229 --> 00:03:57,840 highest priorities has been to 101 00:04:02,390 --> 00:04:00,239 understand active mars changes on the 102 00:04:04,789 --> 00:04:02,400 surface today and we've seen lots of 103 00:04:06,630 --> 00:04:04,799 interesting things new impact craters 104 00:04:09,190 --> 00:04:06,640 dust avalanches 105 00:04:11,670 --> 00:04:09,200 sand bodies shifting 106 00:04:13,910 --> 00:04:11,680 in the polar regions associated with the 107 00:04:16,390 --> 00:04:13,920 seasonal co2 frost we see a whole suite 108 00:04:18,949 --> 00:04:16,400 of bizarre phenomenon 109 00:04:21,670 --> 00:04:18,959 none of these however seem to suggest or 110 00:04:24,070 --> 00:04:21,680 require liquid water in any way 111 00:04:25,670 --> 00:04:24,080 until recently we found found something 112 00:04:26,870 --> 00:04:25,680 that had slipped our attention 113 00:04:28,870 --> 00:04:26,880 previously 114 00:04:30,150 --> 00:04:28,880 that is is quite different from all this 115 00:04:32,950 --> 00:04:30,160 other activity in terms of the 116 00:04:35,030 --> 00:04:32,960 particular environmental requirements 117 00:04:37,030 --> 00:04:35,040 and its behavior 118 00:04:38,870 --> 00:04:37,040 why don't we start the the video as i 119 00:04:41,030 --> 00:04:38,880 describe these in more detail so you can 120 00:04:43,430 --> 00:04:41,040 see this for yourself here's a globe of 121 00:04:44,390 --> 00:04:43,440 mars and we're going to zoom in 122 00:04:46,550 --> 00:04:44,400 on the 123 00:04:49,189 --> 00:04:46,560 southern mid-latitude which is where we 124 00:04:51,590 --> 00:04:49,199 find these features 125 00:04:53,909 --> 00:04:51,600 this big crater there is newton crater 126 00:04:58,629 --> 00:04:53,919 and 127 00:05:00,870 --> 00:04:58,639 there's a crater on its floor 128 00:05:03,110 --> 00:05:00,880 there's the high-rise field of view so 129 00:05:06,230 --> 00:05:03,120 we'll zoom in on that 130 00:05:08,150 --> 00:05:06,240 high-rise images that point at 25 131 00:05:10,550 --> 00:05:08,160 centimeters per pixel so we get very 132 00:05:11,590 --> 00:05:10,560 high resolution so what we're going to 133 00:05:14,790 --> 00:05:11,600 see here 134 00:05:17,270 --> 00:05:14,800 is a time sequence with images taken 135 00:05:18,950 --> 00:05:17,280 weeks to months apart in time cycling 136 00:05:20,870 --> 00:05:18,960 through the year with emphasis on the 137 00:05:21,909 --> 00:05:20,880 late spring and summer 138 00:05:23,990 --> 00:05:21,919 period 139 00:05:28,950 --> 00:05:24,000 so the slope features they're in the 140 00:05:33,830 --> 00:05:31,909 start to form in the late spring 141 00:05:36,710 --> 00:05:33,840 there's the winter time there's early 142 00:05:39,590 --> 00:05:36,720 late spring early summer mid-summer 143 00:05:41,110 --> 00:05:39,600 late summer later summer back to early 144 00:05:45,110 --> 00:05:41,120 spring 145 00:05:47,029 --> 00:05:45,120 and so these form and and grow they 146 00:05:49,350 --> 00:05:47,039 darken 147 00:05:52,710 --> 00:05:49,360 some of them start fading while new 148 00:05:54,710 --> 00:05:52,720 liniments are forming and growing still 149 00:05:58,469 --> 00:05:54,720 eventually they all fade 150 00:06:01,029 --> 00:05:58,479 and eventually they completely disappear 151 00:06:03,270 --> 00:06:01,039 as you can see as we scroll to the north 152 00:06:05,990 --> 00:06:03,280 here there's a very large number of 153 00:06:07,830 --> 00:06:06,000 these flows we estimate about a thousand 154 00:06:09,909 --> 00:06:07,840 of these individual flows in this just 155 00:06:11,990 --> 00:06:09,919 this one crater 156 00:06:14,150 --> 00:06:12,000 however these are actually rare the 157 00:06:16,230 --> 00:06:14,160 sites where we find these are rare we 158 00:06:19,189 --> 00:06:16,240 have found seven confirmed sites and 159 00:06:23,350 --> 00:06:19,199 about 20 candidates that we haven't 160 00:06:27,350 --> 00:06:25,189 something else you can see here sort of 161 00:06:29,029 --> 00:06:27,360 on the right side is where these dark 162 00:06:30,870 --> 00:06:29,039 flows terminate 163 00:06:33,830 --> 00:06:30,880 there is a bright there are bright 164 00:06:36,309 --> 00:06:33,840 smooth areas and that appears to be some 165 00:06:40,390 --> 00:06:36,319 sort of deposit or residue left behind 166 00:06:44,790 --> 00:06:42,790 okay so in the next video that we'll go 167 00:06:47,029 --> 00:06:44,800 right to it we'll show the same uh 168 00:06:50,950 --> 00:06:47,039 crater again but this time we'll show a 169 00:06:53,990 --> 00:06:50,960 3d view of the crater flyover movie and 170 00:06:55,749 --> 00:06:54,000 this time the jpl visualization wizards 171 00:06:58,150 --> 00:06:55,759 have outdone themselves and will show 172 00:06:59,589 --> 00:06:58,160 the time sequence as we fly by in three 173 00:07:02,230 --> 00:06:59,599 dimensions 174 00:07:04,230 --> 00:07:02,240 so here we are zooming in on the crater 175 00:07:07,029 --> 00:07:04,240 this is no vertical exaggeration these 176 00:07:09,670 --> 00:07:07,039 are really steep slopes about 35 degree 177 00:07:15,110 --> 00:07:11,510 these dark flows 178 00:07:16,629 --> 00:07:15,120 appear to emanate from bedrock outcrops 179 00:07:18,870 --> 00:07:16,639 sometimes in places we see them 180 00:07:21,670 --> 00:07:18,880 emanating from rocky slopes where we can 181 00:07:27,430 --> 00:07:21,680 infer shallow bedrock so there is some 182 00:07:32,070 --> 00:07:29,350 now we see these in the there are 183 00:07:33,350 --> 00:07:32,080 several characteristics of of these 184 00:07:35,670 --> 00:07:33,360 sites 185 00:07:37,589 --> 00:07:35,680 that suggest to us that a volatile 186 00:07:39,189 --> 00:07:37,599 material of some sort is involved in 187 00:07:40,710 --> 00:07:39,199 this activity 188 00:07:44,390 --> 00:07:40,720 first they're concentrating the middle 189 00:07:46,070 --> 00:07:44,400 latitudes uh where volatiles might be 190 00:07:48,230 --> 00:07:46,080 more likely to be found 191 00:07:50,070 --> 00:07:48,240 but they also require warm temperatures 192 00:07:51,670 --> 00:07:50,080 so the equator facing slopes in the 193 00:07:53,510 --> 00:07:51,680 mid-latitude especially southern 194 00:07:57,270 --> 00:07:53,520 mid-latitude is the intersection of 195 00:08:02,070 --> 00:07:59,990 and we see these grow incrementally and 196 00:08:05,270 --> 00:08:02,080 fade so all of these behaviors suggest 197 00:08:07,670 --> 00:08:05,280 some sort of volatile material to us 198 00:08:09,670 --> 00:08:07,680 we have one more video here in which we 199 00:08:11,029 --> 00:08:09,680 will look at a particular site of 200 00:08:13,749 --> 00:08:11,039 interest 201 00:08:15,990 --> 00:08:13,759 where 202 00:08:17,189 --> 00:08:16,000 in the southern mid-latitudes on another 203 00:08:18,790 --> 00:08:17,199 crater floor 204 00:08:21,029 --> 00:08:18,800 but this is the one site where we've 205 00:08:24,790 --> 00:08:21,039 observed this activity in 206 00:08:27,830 --> 00:08:24,800 three subsequent martian uh summers so 207 00:08:29,909 --> 00:08:27,840 they definitely repeat every year not 208 00:08:32,469 --> 00:08:29,919 exactly in the same place they may be 209 00:08:34,389 --> 00:08:32,479 more or less active from year to year 210 00:08:36,550 --> 00:08:34,399 this goes by kind of fast but there's 211 00:08:40,870 --> 00:08:36,560 actually three mars summers mixed into 212 00:08:43,029 --> 00:08:40,880 the sequence here as we scroll along 213 00:08:45,509 --> 00:08:43,039 so as i was saying we suspect a volatile 214 00:08:47,829 --> 00:08:45,519 material these slopes are far too warm 215 00:08:50,550 --> 00:08:47,839 for carbon dioxide frost 216 00:08:51,829 --> 00:08:50,560 we have phil's themis instrument on mars 217 00:08:53,990 --> 00:08:51,839 odyssey 218 00:08:55,829 --> 00:08:54,000 to measure the temperatures and we we 219 00:08:57,590 --> 00:08:55,839 measure these temperatures on the 100 220 00:09:01,030 --> 00:08:57,600 meter scale to be from 221 00:09:03,430 --> 00:09:01,040 about minus 23 to plus 27 centigrade 222 00:09:04,470 --> 00:09:03,440 which is minus 10 to plus 223 00:09:06,550 --> 00:09:04,480 80 224 00:09:08,710 --> 00:09:06,560 fahrenheit 225 00:09:10,710 --> 00:09:08,720 so these are temperatures appropriate 226 00:09:13,190 --> 00:09:10,720 for well those above freezing are 227 00:09:16,310 --> 00:09:13,200 appropriate for even pure water 228 00:09:18,949 --> 00:09:16,320 but uh we expect water on mars to be 229 00:09:21,190 --> 00:09:18,959 briny to be salty because we know that 230 00:09:23,509 --> 00:09:21,200 the surface is salty from 231 00:09:25,269 --> 00:09:23,519 all of the past landers and rovers from 232 00:09:27,269 --> 00:09:25,279 martian meteorites from orbital remote 233 00:09:29,509 --> 00:09:27,279 sensing so any water that flows in the 234 00:09:30,550 --> 00:09:29,519 subsurface or surface is going to get 235 00:09:32,949 --> 00:09:30,560 salty 236 00:09:35,110 --> 00:09:32,959 furthermore the salt serves to depress 237 00:09:36,710 --> 00:09:35,120 the freezing point of the water so 238 00:09:38,790 --> 00:09:36,720 in places where it's below freezing and 239 00:09:43,670 --> 00:09:38,800 we see this activity it is still 240 00:09:48,550 --> 00:09:45,910 now so we have this circumstantial 241 00:09:51,190 --> 00:09:48,560 evidence for for water flowing on mars 242 00:09:53,670 --> 00:09:51,200 we have no direct detection of water 243 00:09:55,350 --> 00:09:53,680 there is an instrument on mro called the 244 00:09:58,310 --> 00:09:55,360 compact reconnaissance imaging 245 00:09:59,829 --> 00:09:58,320 spectrometer for mars chrism 246 00:10:03,030 --> 00:09:59,839 which acquires 247 00:10:06,710 --> 00:10:03,040 spectra in many wavelengths 248 00:10:09,269 --> 00:10:06,720 at a maximum a a best scale of about 18 249 00:10:12,630 --> 00:10:09,279 meters per pixel these features are one 250 00:10:13,670 --> 00:10:12,640 to a few uh meters wide 251 00:10:14,470 --> 00:10:13,680 so 252 00:10:16,949 --> 00:10:14,480 uh 253 00:10:20,310 --> 00:10:16,959 they're not fully resolved and they do 254 00:10:21,269 --> 00:10:20,320 not see chrism does not see water 255 00:10:23,990 --> 00:10:21,279 now 256 00:10:25,910 --> 00:10:24,000 we suspect that there is water present 257 00:10:27,910 --> 00:10:25,920 at the surface only in small areas for 258 00:10:30,710 --> 00:10:27,920 short periods of time which would be 259 00:10:32,389 --> 00:10:30,720 consistent with the chrism data 260 00:10:33,829 --> 00:10:32,399 it's important to bear in mind that the 261 00:10:35,509 --> 00:10:33,839 environment of mars is very different 262 00:10:37,190 --> 00:10:35,519 from earth the atmospheric pressure is 263 00:10:39,350 --> 00:10:37,200 less than one percent of that of earth 264 00:10:41,350 --> 00:10:39,360 pure water on these sites at these 265 00:10:42,870 --> 00:10:41,360 temperatures would boil 266 00:10:46,389 --> 00:10:42,880 in spite of it being well below the 267 00:10:48,470 --> 00:10:46,399 boiling point at one bar on earth 268 00:10:52,310 --> 00:10:48,480 now salty water probably doesn't boil 269 00:10:54,870 --> 00:10:52,320 but it still evaporates very rapidly so 270 00:10:57,269 --> 00:10:54,880 we think we can explain that away but 271 00:10:59,590 --> 00:10:57,279 nevertheless we lack that direct 272 00:11:01,829 --> 00:10:59,600 confirmation of water so 273 00:11:04,790 --> 00:11:01,839 how can we understand these for sure how 274 00:11:06,389 --> 00:11:04,800 can we confirm what these are 275 00:11:08,710 --> 00:11:06,399 what we'll be doing is continuing to 276 00:11:10,150 --> 00:11:08,720 acquire mro observations to to 277 00:11:12,870 --> 00:11:10,160 understand all the observational 278 00:11:15,670 --> 00:11:12,880 constraints especially the extremes of 279 00:11:17,829 --> 00:11:15,680 temperature and latitude and season 280 00:11:19,910 --> 00:11:17,839 and then i think it's laboratory 281 00:11:22,310 --> 00:11:19,920 experiments that are really going to 282 00:11:24,230 --> 00:11:22,320 provide some the next major step forward 283 00:11:25,590 --> 00:11:24,240 in understanding these these are small 284 00:11:27,110 --> 00:11:25,600 scale features 285 00:11:29,910 --> 00:11:27,120 so you can simulate these in the 286 00:11:31,030 --> 00:11:29,920 laboratory at only a factor of 10 or a 287 00:11:32,870 --> 00:11:31,040 little more 288 00:11:34,870 --> 00:11:32,880 reduced scale 289 00:11:37,110 --> 00:11:34,880 that's much better than you can do with 290 00:11:38,470 --> 00:11:37,120 many geologic processes like earthquakes 291 00:11:42,069 --> 00:11:38,480 where it's 292 00:11:44,069 --> 00:11:42,079 many factors of 10 a difference in scale 293 00:11:45,670 --> 00:11:44,079 and and controlling the atmospheric 294 00:11:47,750 --> 00:11:45,680 pressure and temperatures to mars-like 295 00:11:49,269 --> 00:11:47,760 conditions is is quite possible there's 296 00:11:53,110 --> 00:11:49,279 quite a number of labs around this 297 00:11:54,550 --> 00:11:53,120 country and europe that can do this 298 00:11:57,750 --> 00:11:54,560 furthermore there are future missions 299 00:11:59,910 --> 00:11:57,760 coming the trace gas orbiter from 2016 300 00:12:01,509 --> 00:11:59,920 might acquire some interesting 301 00:12:03,990 --> 00:12:01,519 observations and we're currently 302 00:12:05,590 --> 00:12:04,000 discussing what it might see 303 00:12:08,629 --> 00:12:05,600 and there's always a possibility of 304 00:12:12,069 --> 00:12:08,639 future landers and rovers 305 00:12:14,710 --> 00:12:12,079 now uh we see these uh we've heard about 306 00:12:16,870 --> 00:12:14,720 the gullies on mars previously and these 307 00:12:18,550 --> 00:12:16,880 uh flows are associated with small 308 00:12:20,310 --> 00:12:18,560 channels in some place so what is the 309 00:12:23,110 --> 00:12:20,320 relationship between these features and 310 00:12:25,110 --> 00:12:23,120 flows to address that in more detail 311 00:12:26,870 --> 00:12:25,120 we'll turn to colin 312 00:12:29,190 --> 00:12:26,880 thanks alfred uh 313 00:12:31,269 --> 00:12:29,200 i'm going to talk a bit about martian 314 00:12:32,870 --> 00:12:31,279 gullies and their activity and how they 315 00:12:34,629 --> 00:12:32,880 compare with these dark flows that we're 316 00:12:37,990 --> 00:12:34,639 talking about today 317 00:12:40,230 --> 00:12:38,000 i if i could have the first slide 318 00:12:43,030 --> 00:12:40,240 gullies have been discussed frequently 319 00:12:45,190 --> 00:12:43,040 as evidence for water on mars 320 00:12:47,590 --> 00:12:45,200 this is an image of a crater in the 321 00:12:49,670 --> 00:12:47,600 southern mid-latitudes where you can see 322 00:12:51,430 --> 00:12:49,680 a number of gullies on the 323 00:12:52,790 --> 00:12:51,440 near the top of the image on the pole 324 00:12:54,790 --> 00:12:52,800 facing slope 325 00:12:56,310 --> 00:12:54,800 and the upper arrow is indicating one 326 00:12:57,269 --> 00:12:56,320 gully that i'll talk about a bit more 327 00:12:58,790 --> 00:12:57,279 later 328 00:13:00,710 --> 00:12:58,800 this is also a site where we've seen 329 00:13:02,629 --> 00:13:00,720 these dark flows the lower arrow 330 00:13:04,470 --> 00:13:02,639 indicates a site that i'll talk about 331 00:13:06,389 --> 00:13:04,480 where those are present 332 00:13:08,470 --> 00:13:06,399 so gullies have been discussed quite a 333 00:13:10,629 --> 00:13:08,480 bit as evidence for water on mars if i 334 00:13:13,430 --> 00:13:10,639 could have the next slide 335 00:13:15,590 --> 00:13:13,440 uh these tend to uh consist of an upper 336 00:13:17,670 --> 00:13:15,600 alcove feeding into a channel and then 337 00:13:20,230 --> 00:13:17,680 ultimately an apron and they look very 338 00:13:21,829 --> 00:13:20,240 much like water carved features on earth 339 00:13:23,509 --> 00:13:21,839 and these were first reported about 10 340 00:13:25,430 --> 00:13:23,519 years ago and since then there's been 341 00:13:27,030 --> 00:13:25,440 quite a bit of discussion about 342 00:13:28,470 --> 00:13:27,040 various processes that might have been 343 00:13:30,629 --> 00:13:28,480 involved in forming these but mostly 344 00:13:32,629 --> 00:13:30,639 centered around liquid water 345 00:13:34,790 --> 00:13:32,639 with highrise we've been very interested 346 00:13:37,190 --> 00:13:34,800 to learn more about these and we've been 347 00:13:38,949 --> 00:13:37,200 monitoring a number of gully sites as 348 00:13:40,790 --> 00:13:38,959 the context camera 349 00:13:42,310 --> 00:13:40,800 looking for changes 350 00:13:44,150 --> 00:13:42,320 uh we've 351 00:13:45,350 --> 00:13:44,160 i've seen a number of gullies that have 352 00:13:48,470 --> 00:13:45,360 been active 353 00:13:50,389 --> 00:13:48,480 and if i could have the next slide 354 00:13:52,550 --> 00:13:50,399 this is an example comparing this in the 355 00:13:54,230 --> 00:13:52,560 next image if you look at the lower left 356 00:13:56,389 --> 00:13:54,240 you'll see near the toe of a gully 357 00:13:58,310 --> 00:13:56,399 channel a dark deposit forms 358 00:14:00,310 --> 00:13:58,320 and we've seen a range of different 359 00:14:01,269 --> 00:14:00,320 activity in gullies 360 00:14:03,509 --> 00:14:01,279 but 361 00:14:06,150 --> 00:14:03,519 we've also seen a tendency uh given the 362 00:14:07,990 --> 00:14:06,160 timing constraints for this activity uh 363 00:14:09,910 --> 00:14:08,000 to occur in the colder times of year in 364 00:14:11,990 --> 00:14:09,920 fact for some of the best constrained 365 00:14:14,230 --> 00:14:12,000 events it tends to be in the winter 366 00:14:16,230 --> 00:14:14,240 and gullies in the martian mid-latitudes 367 00:14:18,069 --> 00:14:16,240 tend to be on pole facing slopes which 368 00:14:21,189 --> 00:14:18,079 are cold and especially cold in the 369 00:14:24,389 --> 00:14:21,199 winter when carbon dioxide frost forms 370 00:14:26,790 --> 00:14:24,399 so these gully activity is quite 371 00:14:28,389 --> 00:14:26,800 distinct from what we see in this slope 372 00:14:30,389 --> 00:14:28,399 linear 373 00:14:32,870 --> 00:14:30,399 if i could have the next slide 374 00:14:34,710 --> 00:14:32,880 uh this is again the same site that 375 00:14:37,110 --> 00:14:34,720 alfred showed in his third movie uh this 376 00:14:38,949 --> 00:14:37,120 is an example of slope linear in the 377 00:14:41,110 --> 00:14:38,959 same crater uh where 378 00:14:42,629 --> 00:14:41,120 that active gully that i just showed is 379 00:14:44,710 --> 00:14:42,639 present 380 00:14:46,389 --> 00:14:44,720 the activity is uh quite distinct the 381 00:14:48,150 --> 00:14:46,399 gullies are tend to be on the pole 382 00:14:51,509 --> 00:14:48,160 facing slopes tend to be active in the 383 00:14:53,509 --> 00:14:51,519 winter and tend to be single events uh 384 00:14:55,750 --> 00:14:53,519 but sometimes at a much larger scale 385 00:14:57,670 --> 00:14:55,760 than what we observe with these flows 386 00:15:00,790 --> 00:14:57,680 uh the scale of gullies can be a 387 00:15:02,389 --> 00:15:00,800 kilometer scale and we see in some cases 388 00:15:03,509 --> 00:15:02,399 quite significant 389 00:15:06,790 --> 00:15:03,519 changes 390 00:15:08,389 --> 00:15:06,800 uh whereas with these smaller dark flows 391 00:15:10,949 --> 00:15:08,399 these tend to be on equator facing 392 00:15:12,870 --> 00:15:10,959 warmer slopes active in the summer 393 00:15:13,829 --> 00:15:12,880 and they tend the individual 394 00:15:15,509 --> 00:15:13,839 flows 395 00:15:18,230 --> 00:15:15,519 tend to be much smaller 396 00:15:20,949 --> 00:15:18,240 and they're so far not associated with 397 00:15:22,389 --> 00:15:20,959 any visible changes to the topography as 398 00:15:23,910 --> 00:15:22,399 you go from year to year things look 399 00:15:25,509 --> 00:15:23,920 about the same 400 00:15:26,949 --> 00:15:25,519 these are sometimes associated with 401 00:15:29,590 --> 00:15:26,959 small channels 402 00:15:31,110 --> 00:15:29,600 uh but not with in most cases not with 403 00:15:33,350 --> 00:15:31,120 the larger gullies that have been talked 404 00:15:34,550 --> 00:15:33,360 about quite a bit previously 405 00:15:36,389 --> 00:15:34,560 so we've got 406 00:15:37,990 --> 00:15:36,399 two interesting and different types of 407 00:15:40,550 --> 00:15:38,000 activity here but these dark flows that 408 00:15:42,389 --> 00:15:40,560 we're talking about today are fairly 409 00:15:43,509 --> 00:15:42,399 distinct from the larger scale gully 410 00:15:46,710 --> 00:15:43,519 activity 411 00:15:48,389 --> 00:15:46,720 that in the previously reported gullies 412 00:15:50,710 --> 00:15:48,399 so with that i'll pass things along to 413 00:15:52,389 --> 00:15:50,720 phil christensen for a larger scale view 414 00:15:55,269 --> 00:15:52,399 of these results 415 00:15:58,069 --> 00:15:55,279 thanks colin uh in the last 15 years 416 00:15:59,749 --> 00:15:58,079 we've certainly discovered that mars has 417 00:16:02,310 --> 00:15:59,759 a lot of water 418 00:16:03,749 --> 00:16:02,320 much of that water is in the form of ice 419 00:16:05,189 --> 00:16:03,759 in the polar regions or the high 420 00:16:06,710 --> 00:16:05,199 latitudes 421 00:16:08,230 --> 00:16:06,720 and at those places 422 00:16:10,949 --> 00:16:08,240 that water is going to be frozen 423 00:16:12,870 --> 00:16:10,959 throughout the year it's just too cold 424 00:16:15,749 --> 00:16:12,880 to ever form a liquid 425 00:16:18,790 --> 00:16:15,759 what makes these new observations so 426 00:16:20,389 --> 00:16:18,800 interesting is that they occur at much 427 00:16:22,470 --> 00:16:20,399 lower latitudes where the temperatures 428 00:16:25,189 --> 00:16:22,480 are much warmer and where it's actually 429 00:16:27,110 --> 00:16:25,199 possible for liquid water 430 00:16:28,790 --> 00:16:27,120 to exist 431 00:16:30,389 --> 00:16:28,800 so to put this in a little bit of a 432 00:16:32,389 --> 00:16:30,399 perspective if we could take a look at 433 00:16:36,710 --> 00:16:32,399 the first slide 434 00:16:38,790 --> 00:16:36,720 what this shows is a global map of mars 435 00:16:41,670 --> 00:16:38,800 from pole to pole 436 00:16:44,550 --> 00:16:41,680 of the mars odyssey neutron spectrometer 437 00:16:46,870 --> 00:16:44,560 data which measures water or hydrogen in 438 00:16:48,870 --> 00:16:46,880 the upper meter of the surface 439 00:16:50,949 --> 00:16:48,880 what that experiment showed was that at 440 00:16:52,790 --> 00:16:50,959 the high latitudes near the poles and 441 00:16:54,230 --> 00:16:52,800 these in this image these blue colors 442 00:16:57,670 --> 00:16:54,240 represent places where there's a 443 00:16:58,949 --> 00:16:57,680 significant amount 70 80 90 444 00:17:00,710 --> 00:16:58,959 of the surface 445 00:17:02,230 --> 00:17:00,720 being ice 446 00:17:03,829 --> 00:17:02,240 so there was never there hasn't been a 447 00:17:07,270 --> 00:17:03,839 question for some time now that there's 448 00:17:08,949 --> 00:17:07,280 ice on mars but it's uh it's a typically 449 00:17:11,029 --> 00:17:08,959 very high latitudes 450 00:17:14,309 --> 00:17:11,039 the next piece of the story came the 451 00:17:16,710 --> 00:17:14,319 next slide shows some 452 00:17:19,270 --> 00:17:16,720 small impacts where nature has helped us 453 00:17:21,350 --> 00:17:19,280 out to probe a little bit deeper these 454 00:17:23,510 --> 00:17:21,360 are small craters where the impact is 455 00:17:24,470 --> 00:17:23,520 actually exposed water ice onto the 456 00:17:27,669 --> 00:17:24,480 surface 457 00:17:29,909 --> 00:17:27,679 and this extends toward the equator the 458 00:17:32,870 --> 00:17:29,919 regions where we know 459 00:17:34,789 --> 00:17:32,880 ice is present but again these are 460 00:17:36,470 --> 00:17:34,799 fairly high latitudes up you know 461 00:17:38,470 --> 00:17:36,480 northern canada 462 00:17:40,710 --> 00:17:38,480 type of locations 463 00:17:41,750 --> 00:17:40,720 the next slide shows the locations of 464 00:17:43,830 --> 00:17:41,760 these 465 00:17:45,350 --> 00:17:43,840 slope flows that alfred and his team 466 00:17:47,110 --> 00:17:45,360 have discovered 467 00:17:48,870 --> 00:17:47,120 and what we see is these are much closer 468 00:17:50,710 --> 00:17:48,880 to the equator 469 00:17:52,470 --> 00:17:50,720 they're in regions as alfred mentioned 470 00:17:54,070 --> 00:17:52,480 where the surface temperatures are much 471 00:17:56,549 --> 00:17:54,080 warmer 472 00:17:59,669 --> 00:17:56,559 so this is providing even more evidence 473 00:18:02,230 --> 00:17:59,679 that water is closer to the equator than 474 00:18:03,430 --> 00:18:02,240 we thought before and now it's in a zone 475 00:18:04,630 --> 00:18:03,440 where the temperatures are going to 476 00:18:06,150 --> 00:18:04,640 allow that 477 00:18:09,270 --> 00:18:06,160 water to 478 00:18:10,950 --> 00:18:09,280 potentially be uh be liquid at various 479 00:18:13,350 --> 00:18:10,960 times throughout the year 480 00:18:15,190 --> 00:18:13,360 now these mid-latitudes are i think 481 00:18:17,590 --> 00:18:15,200 extremely interesting there's in 482 00:18:19,190 --> 00:18:17,600 addition to these flows and the gullies 483 00:18:21,029 --> 00:18:19,200 we've seen evidence of materials that 484 00:18:23,750 --> 00:18:21,039 looks like it's pasted onto the surface 485 00:18:25,669 --> 00:18:23,760 as if it was a snow or ice deposit 486 00:18:28,070 --> 00:18:25,679 knobby mantle terrains throughout this 487 00:18:29,909 --> 00:18:28,080 region that might be ice that's being uh 488 00:18:32,150 --> 00:18:29,919 that's evaporating 489 00:18:34,630 --> 00:18:32,160 so these mid-latitudes uh are 490 00:18:37,350 --> 00:18:34,640 i think a very interesting place on mars 491 00:18:39,430 --> 00:18:37,360 uh the final slide shows uh mineral 492 00:18:41,430 --> 00:18:39,440 evidence uh alfred mentioned the 493 00:18:44,070 --> 00:18:41,440 possibility that these were salty or 494 00:18:45,510 --> 00:18:44,080 briny flows the red dots there show 495 00:18:47,669 --> 00:18:45,520 places where we 496 00:18:50,390 --> 00:18:47,679 think we have evidence mineral evidence 497 00:18:52,230 --> 00:18:50,400 for actual salt deposits on mars and you 498 00:18:53,909 --> 00:18:52,240 can see there's a very nice correlation 499 00:18:56,470 --> 00:18:53,919 between where these salt deposits are 500 00:18:58,070 --> 00:18:56,480 occurring and where these potentially 501 00:19:00,230 --> 00:18:58,080 briny 502 00:19:01,669 --> 00:19:00,240 surface flows or near surface flows are 503 00:19:04,230 --> 00:19:01,679 occurring 504 00:19:06,070 --> 00:19:04,240 so again a very nice correlation 505 00:19:07,590 --> 00:19:06,080 so in conclusion i would i would argue 506 00:19:09,270 --> 00:19:07,600 that the mid-latitudes really are 507 00:19:11,350 --> 00:19:09,280 turning out to be the place on mars 508 00:19:13,590 --> 00:19:11,360 where a lot of the action is 509 00:19:15,590 --> 00:19:13,600 there are high enough latitudes and cold 510 00:19:17,830 --> 00:19:15,600 enough at times where snow and ice can 511 00:19:20,390 --> 00:19:17,840 accumulate and yet 512 00:19:23,270 --> 00:19:20,400 importantly they're warm enough 513 00:19:24,710 --> 00:19:23,280 at times where liquid water can actually 514 00:19:26,870 --> 00:19:24,720 exist 515 00:19:28,630 --> 00:19:26,880 so for me this is sort of the beginning 516 00:19:31,990 --> 00:19:28,640 of a process the beginning of a 517 00:19:34,070 --> 00:19:32,000 scientific process where 518 00:19:35,430 --> 00:19:34,080 we've just started as alfred mentioned 519 00:19:37,270 --> 00:19:35,440 there's questions regarding these 520 00:19:39,590 --> 00:19:37,280 observations but now the scientific 521 00:19:41,830 --> 00:19:39,600 community can really turn to them and 522 00:19:43,430 --> 00:19:41,840 really begin to probe the details of of 523 00:19:45,750 --> 00:19:43,440 what these observations are telling us 524 00:19:47,270 --> 00:19:45,760 about water on mars 525 00:19:49,990 --> 00:19:47,280 one of the reasons we're interested in 526 00:19:52,950 --> 00:19:50,000 water of course is the potential 527 00:19:55,190 --> 00:19:52,960 relationship to life and here to talk a 528 00:19:56,310 --> 00:19:55,200 little bit more about that is lisa pratt 529 00:19:58,470 --> 00:19:56,320 thanks phil 530 00:20:00,870 --> 00:19:58,480 i am really very pleased to be here 531 00:20:03,990 --> 00:20:00,880 today to comment on this report because 532 00:20:06,070 --> 00:20:04,000 i think this is an eye-opening discovery 533 00:20:08,230 --> 00:20:06,080 that'll really help us begin the 534 00:20:09,669 --> 00:20:08,240 planning process for future missions 535 00:20:12,230 --> 00:20:09,679 specifically 536 00:20:13,350 --> 00:20:12,240 looking for signs of life on present day 537 00:20:15,669 --> 00:20:13,360 mars 538 00:20:18,630 --> 00:20:15,679 we've waited a long time as a community 539 00:20:21,750 --> 00:20:18,640 for a place where we could monitor 540 00:20:24,149 --> 00:20:21,760 processes before during and after some 541 00:20:27,110 --> 00:20:24,159 type of recurrent event that suggested 542 00:20:29,510 --> 00:20:27,120 you might have a brine close enough to 543 00:20:32,230 --> 00:20:29,520 the surface that you might 544 00:20:35,270 --> 00:20:32,240 be able to see evidence of some kind of 545 00:20:37,430 --> 00:20:35,280 a biological process and again the the 546 00:20:39,750 --> 00:20:37,440 difficulty has been that mars is simply 547 00:20:41,990 --> 00:20:39,760 too large a planet to keep an eye on 548 00:20:43,669 --> 00:20:42,000 every place at all times and we've we've 549 00:20:45,510 --> 00:20:43,679 needed a way to really focus our 550 00:20:48,230 --> 00:20:45,520 instruments and think about the 551 00:20:51,510 --> 00:20:48,240 engineering um decisions that need to be 552 00:20:53,510 --> 00:20:51,520 made for future land admissions or for 553 00:20:55,750 --> 00:20:53,520 future orbiting missions and i i really 554 00:20:58,230 --> 00:20:55,760 think we now have it 555 00:21:00,230 --> 00:20:58,240 if we then start to talk about well what 556 00:21:02,549 --> 00:21:00,240 do we know about analog environments on 557 00:21:03,990 --> 00:21:02,559 earth i think we can bring up the last 558 00:21:06,149 --> 00:21:04,000 image here 559 00:21:09,029 --> 00:21:06,159 probably the best analog environments on 560 00:21:11,510 --> 00:21:09,039 earth where we have looked at 561 00:21:14,149 --> 00:21:11,520 the habitability and the specific forms 562 00:21:16,630 --> 00:21:14,159 of life in these permafrost environments 563 00:21:17,830 --> 00:21:16,640 would be the siberian permafrost 564 00:21:20,230 --> 00:21:17,840 we take what we know about that 565 00:21:21,990 --> 00:21:20,240 environment and try to then layer it on 566 00:21:24,950 --> 00:21:22,000 to what we infer about the subsurface of 567 00:21:26,870 --> 00:21:24,960 mars we get this simple cartoon 568 00:21:29,270 --> 00:21:26,880 we think that there might be two ways in 569 00:21:31,270 --> 00:21:29,280 which water could reside 570 00:21:34,470 --> 00:21:31,280 water or brines deeper in the crust 571 00:21:36,230 --> 00:21:34,480 either in a a connected fracture network 572 00:21:37,990 --> 00:21:36,240 like the one you see here on the left in 573 00:21:40,070 --> 00:21:38,000 this image that would 574 00:21:42,390 --> 00:21:40,080 penetrate below the permafrost 575 00:21:44,470 --> 00:21:42,400 potentially into a deep subpermafrost 576 00:21:48,149 --> 00:21:44,480 brine but on the right we can also 577 00:21:51,270 --> 00:21:48,159 imagine that as a result of pockets and 578 00:21:53,590 --> 00:21:51,280 patches of snow and ice we might have 579 00:21:55,830 --> 00:21:53,600 lenses or pockets 580 00:21:58,630 --> 00:21:55,840 in this diagram labeled cryopegs 581 00:22:01,029 --> 00:21:58,640 cryopegs on earth actually refer to 582 00:22:03,350 --> 00:22:01,039 bodies of water that are very cold and 583 00:22:04,870 --> 00:22:03,360 salty and because of their salt content 584 00:22:07,350 --> 00:22:04,880 they remain liquid even though the 585 00:22:10,230 --> 00:22:07,360 surrounding permafrost can be very very 586 00:22:12,390 --> 00:22:10,240 cold you also see in this diagram 587 00:22:15,110 --> 00:22:12,400 conceptually that there there might be a 588 00:22:17,510 --> 00:22:15,120 very thin layer at the top of mars where 589 00:22:19,590 --> 00:22:17,520 if there was seasonally available briny 590 00:22:21,750 --> 00:22:19,600 water you could have some sort of 591 00:22:24,149 --> 00:22:21,760 biological activity in a photic zone you 592 00:22:26,870 --> 00:22:24,159 might actually allow organisms to take 593 00:22:29,590 --> 00:22:26,880 advantage of the energy from sunlight 594 00:22:31,669 --> 00:22:29,600 and below that a slightly thicker active 595 00:22:34,230 --> 00:22:31,679 zone meaning the layer that seasonally 596 00:22:37,190 --> 00:22:34,240 warms up enough to 597 00:22:38,630 --> 00:22:37,200 to melt melt snow or ice and again have 598 00:22:40,950 --> 00:22:38,640 some sort of a brine and then an 599 00:22:45,430 --> 00:22:40,960 underlying permafrost and again very 600 00:22:48,149 --> 00:22:45,440 importantly a deeper subpermafrost brine 601 00:22:50,950 --> 00:22:48,159 so the next big question is to try to 602 00:22:53,430 --> 00:22:50,960 understand the origin and source 603 00:22:55,990 --> 00:22:53,440 of these of these flows that alfred and 604 00:22:57,909 --> 00:22:56,000 his team have inferred on mars to think 605 00:23:00,630 --> 00:22:57,919 about them in terms of whether or not 606 00:23:03,190 --> 00:23:00,640 they might provide a conduit or a 607 00:23:05,430 --> 00:23:03,200 connectivity to a larger deeper brine 608 00:23:07,669 --> 00:23:05,440 pool or if in fact these 609 00:23:09,190 --> 00:23:07,679 these fluids are just isolated patches 610 00:23:11,190 --> 00:23:09,200 and pockets 611 00:23:12,710 --> 00:23:11,200 no matter which it is 612 00:23:14,630 --> 00:23:12,720 as i mentioned before 613 00:23:18,070 --> 00:23:14,640 this is an enormous opportunity for the 614 00:23:20,310 --> 00:23:18,080 scientific community to really begin to 615 00:23:23,029 --> 00:23:20,320 focus on the specific changes that 616 00:23:25,029 --> 00:23:23,039 create the uh the the darkening that's 617 00:23:27,750 --> 00:23:25,039 been reported to try to determine if 618 00:23:29,990 --> 00:23:27,760 that's mineralogical it could be a 619 00:23:32,390 --> 00:23:30,000 hydration it could also be an oxidation 620 00:23:34,310 --> 00:23:32,400 or a reduction it also gives us the 621 00:23:36,070 --> 00:23:34,320 opportunity to focus 622 00:23:39,029 --> 00:23:36,080 future orbiting instruments where we 623 00:23:40,950 --> 00:23:39,039 could look upwind and downwind of those 624 00:23:43,430 --> 00:23:40,960 individual features or that band of 625 00:23:46,230 --> 00:23:43,440 features and look for the possibility of 626 00:23:48,630 --> 00:23:46,240 anomalous releases of either chemically 627 00:23:51,029 --> 00:23:48,640 reduced gases like methane and hydrogen 628 00:23:53,190 --> 00:23:51,039 sulfide or even with the possibility 629 00:23:54,950 --> 00:23:53,200 that this gets a habitable zone up into 630 00:23:57,350 --> 00:23:54,960 the photic region 631 00:23:59,029 --> 00:23:57,360 possibly the release of of an oxidized 632 00:24:01,430 --> 00:23:59,039 gas like oxygen 633 00:24:03,909 --> 00:24:01,440 i really think that this is a very 634 00:24:05,350 --> 00:24:03,919 exciting discovery because it is our 635 00:24:06,710 --> 00:24:05,360 first chance 636 00:24:09,590 --> 00:24:06,720 to see 637 00:24:11,269 --> 00:24:09,600 an environment on mars that might allow 638 00:24:14,149 --> 00:24:11,279 for the expression of an active 639 00:24:16,549 --> 00:24:14,159 biological process if there is present 640 00:24:19,590 --> 00:24:16,559 day life on mars and with that i'll turn 641 00:24:21,669 --> 00:24:19,600 it back to steve okay thank you lisa and 642 00:24:22,789 --> 00:24:21,679 now we'll take questions from the press 643 00:24:24,950 --> 00:24:22,799 we have 644 00:24:26,870 --> 00:24:24,960 questions to begin with at two of our 645 00:24:28,870 --> 00:24:26,880 nasa centers in california starting with 646 00:24:34,789 --> 00:24:28,880 the jet propulsion laboratory please go 647 00:24:38,870 --> 00:24:37,350 yes i know that you mentioned that uh 648 00:24:40,630 --> 00:24:38,880 now the work begins in terms of 649 00:24:43,029 --> 00:24:40,640 identifying the source 650 00:24:45,909 --> 00:24:43,039 of the water but are there any working 651 00:24:49,590 --> 00:24:45,919 theories as to what could possibly be a 652 00:24:51,110 --> 00:24:49,600 source for this uh theoretical water 653 00:24:54,070 --> 00:24:51,120 uh yes 654 00:24:56,149 --> 00:24:54,080 we have too many theories maybe uh 655 00:25:00,149 --> 00:24:56,159 this is a tough question 656 00:25:02,149 --> 00:25:00,159 it could be from carried by gas salts 657 00:25:05,430 --> 00:25:02,159 have this uh interesting property of 658 00:25:07,510 --> 00:25:05,440 actually absorbing moisture from the air 659 00:25:09,750 --> 00:25:07,520 and it could be subsurface 660 00:25:11,909 --> 00:25:09,760 gas flow as well from sublimating ice 661 00:25:14,230 --> 00:25:11,919 bodies for example 662 00:25:15,909 --> 00:25:14,240 the other possibility is that uh similar 663 00:25:17,830 --> 00:25:15,919 to what lisa showed there are actually 664 00:25:20,710 --> 00:25:17,840 pockets of brine 665 00:25:23,269 --> 00:25:20,720 uh in the crust and you know if there 666 00:25:25,350 --> 00:25:23,279 were very concentrated brines associated 667 00:25:27,990 --> 00:25:25,360 even with the those chloride deposits 668 00:25:30,149 --> 00:25:28,000 that phil showed that were quite ancient 669 00:25:32,070 --> 00:25:30,159 that briny water is cold enough to be 670 00:25:34,549 --> 00:25:32,080 stable over geologic time so then you 671 00:25:36,950 --> 00:25:34,559 need some process by which it is is 672 00:25:37,990 --> 00:25:36,960 brought and released to the surface 673 00:25:38,950 --> 00:25:38,000 these 674 00:25:40,789 --> 00:25:38,960 may be 675 00:25:42,630 --> 00:25:40,799 you know low probability sorts of 676 00:25:43,990 --> 00:25:42,640 scenarios but these are also rare 677 00:25:45,590 --> 00:25:44,000 features so 678 00:25:47,830 --> 00:25:45,600 that's where we are now and trying to 679 00:25:49,350 --> 00:25:47,840 understand this 680 00:25:51,350 --> 00:25:49,360 okay thank you uh we have another 681 00:25:54,070 --> 00:25:51,360 question from jpl uh would you please 682 00:25:56,630 --> 00:25:54,080 state your name and affiliation 683 00:26:01,430 --> 00:25:56,640 and go ahead 684 00:26:06,470 --> 00:26:04,310 uh my question is uh how is the mars 685 00:26:08,230 --> 00:26:06,480 rover curiosity able to follow up on 686 00:26:10,870 --> 00:26:08,240 this new information when it when it's 687 00:26:13,510 --> 00:26:10,880 launched to mars 688 00:26:15,750 --> 00:26:13,520 uh well one experiment that has on board 689 00:26:18,470 --> 00:26:15,760 is the tunable laser spectrometer which 690 00:26:20,470 --> 00:26:18,480 can measure among other things methane 691 00:26:22,950 --> 00:26:20,480 so if there actually is methane being 692 00:26:24,710 --> 00:26:22,960 produced somewhere on the planet it has 693 00:26:26,070 --> 00:26:24,720 the sensitivity that it ought to be able 694 00:26:27,830 --> 00:26:26,080 to pick that up 695 00:26:29,029 --> 00:26:27,840 and if there's a seasonal component i'd 696 00:26:31,110 --> 00:26:29,039 be able to 697 00:26:33,590 --> 00:26:31,120 see that also since 698 00:26:35,510 --> 00:26:33,600 curiosity is expected to last at least 699 00:26:37,750 --> 00:26:35,520 one mars year 700 00:26:40,230 --> 00:26:37,760 other than that it can't follow it up it 701 00:26:41,430 --> 00:26:40,240 can't go to these 702 00:26:43,590 --> 00:26:41,440 sites that 703 00:26:46,470 --> 00:26:43,600 alfred just showed because they're too 704 00:26:49,190 --> 00:26:46,480 far of a southern latitude so that the 705 00:26:51,190 --> 00:26:49,200 rover hasn't been designed to do that 706 00:26:53,750 --> 00:26:51,200 but more importantly it's not designed 707 00:26:55,590 --> 00:26:53,760 to land on those steep slopes 708 00:26:57,830 --> 00:26:55,600 which that would be bad 709 00:27:00,310 --> 00:26:57,840 but then number three is there is a 710 00:27:03,669 --> 00:27:00,320 planetary protection concern that if 711 00:27:08,470 --> 00:27:03,679 these are features showing 712 00:27:12,470 --> 00:27:10,710 curiosity has not been 713 00:27:15,110 --> 00:27:12,480 fully sterilized so it wouldn't be 714 00:27:18,630 --> 00:27:15,120 allowed to go there for fear of actually 715 00:27:22,070 --> 00:27:18,640 contaminating the planet with earth life 716 00:27:25,190 --> 00:27:22,080 and so for those reasons uh curiosity 717 00:27:28,389 --> 00:27:25,200 can do some in helping uh explore these 718 00:27:30,870 --> 00:27:28,399 areas and and mars on a global scale but 719 00:27:32,830 --> 00:27:30,880 it can't go there specifically because 720 00:27:37,190 --> 00:27:32,840 you have to plan for those 721 00:27:41,750 --> 00:27:39,669 okay let's go to ames research center 722 00:27:46,549 --> 00:27:41,760 for the next question your name and 723 00:27:51,590 --> 00:27:49,110 it's john fowler i'm the science editor 724 00:27:55,190 --> 00:27:51,600 for ktvu television you say it's 725 00:27:57,430 --> 00:27:55,200 suggestive of liquid water what do you 726 00:27:58,789 --> 00:27:57,440 need to rule out 727 00:28:01,350 --> 00:27:58,799 to be 728 00:28:04,870 --> 00:28:01,360 certain and it looks like a duck quacks 729 00:28:07,190 --> 00:28:04,880 like a duck isn't it a duck 730 00:28:09,029 --> 00:28:07,200 right well it it looks like water to 731 00:28:10,070 --> 00:28:09,039 high rise but uh 732 00:28:11,909 --> 00:28:10,080 grissom 733 00:28:14,230 --> 00:28:11,919 which can actually detect the 734 00:28:15,750 --> 00:28:14,240 mineralogic signature of water has not 735 00:28:17,190 --> 00:28:15,760 been able to confirm this there are 736 00:28:18,630 --> 00:28:17,200 reasons for this 737 00:28:19,909 --> 00:28:18,640 we're going to keep trying with chrism 738 00:28:22,070 --> 00:28:19,919 by the way 739 00:28:24,149 --> 00:28:22,080 they have a super resolution mode that 740 00:28:25,830 --> 00:28:24,159 that increases the resolution at least 741 00:28:28,230 --> 00:28:25,840 in one dimension 742 00:28:29,830 --> 00:28:28,240 also by observing uh different seasons 743 00:28:31,750 --> 00:28:29,840 and differencing the specter that'd be 744 00:28:33,990 --> 00:28:31,760 another way to tease out some subtleties 745 00:28:37,750 --> 00:28:34,000 in the spectrum 746 00:28:39,590 --> 00:28:37,760 but uh as i said before uh i think it's 747 00:28:42,149 --> 00:28:39,600 going to be laboratory experiments on 748 00:28:44,789 --> 00:28:42,159 earth that really give us the the best 749 00:28:47,350 --> 00:28:44,799 confirmation or refutation 750 00:28:49,190 --> 00:28:47,360 if if we can show a mechanism of 751 00:28:51,350 --> 00:28:49,200 matching these observations with or 752 00:28:53,110 --> 00:28:51,360 without water in the lab 753 00:28:54,870 --> 00:28:53,120 that i think that would be very powerful 754 00:28:57,350 --> 00:28:54,880 i'm looking forward to 755 00:28:59,029 --> 00:28:57,360 the publication of these observations as 756 00:29:02,310 --> 00:28:59,039 motivation to those who do such 757 00:29:05,909 --> 00:29:04,149 all right and we have a question here at 758 00:29:08,630 --> 00:29:05,919 headquarters please go ahead 759 00:29:10,389 --> 00:29:08,640 maggie with cronkite news service um 760 00:29:11,909 --> 00:29:10,399 you guys mentioned the 761 00:29:13,510 --> 00:29:11,919 via tool 762 00:29:14,789 --> 00:29:13,520 i guess characteristics of what was 763 00:29:16,710 --> 00:29:14,799 found at the 764 00:29:19,830 --> 00:29:16,720 lower latitudes am i correct 765 00:29:21,830 --> 00:29:19,840 i'm in the brine water i 766 00:29:23,830 --> 00:29:21,840 an average reader i certainly don't 767 00:29:25,510 --> 00:29:23,840 necessarily get that so can you relate 768 00:29:26,710 --> 00:29:25,520 that to a substance that i would 769 00:29:28,630 --> 00:29:26,720 understand 770 00:29:30,070 --> 00:29:28,640 from a day-to-day use if 771 00:29:33,750 --> 00:29:30,080 pure water 772 00:29:36,470 --> 00:29:33,760 in this environment would boil what is 773 00:29:38,389 --> 00:29:36,480 what is what you found 774 00:29:40,549 --> 00:29:38,399 does that make sense right so 775 00:29:42,389 --> 00:29:40,559 on earth we we don't 776 00:29:44,470 --> 00:29:42,399 commonly encounter these highly 777 00:29:46,389 --> 00:29:44,480 concentrated brines because there's so 778 00:29:48,230 --> 00:29:46,399 much water this is the water world and 779 00:29:51,110 --> 00:29:48,240 it gets diluted by all the rainfall and 780 00:29:52,710 --> 00:29:51,120 so forth sea water is salty 781 00:29:54,710 --> 00:29:52,720 uh it actually only depresses the 782 00:29:57,029 --> 00:29:54,720 freezing point by about four degrees 783 00:29:59,110 --> 00:29:57,039 fahrenheit so it's not 784 00:30:00,630 --> 00:29:59,120 probably not as salty as the water we're 785 00:30:03,590 --> 00:30:00,640 talking about here 786 00:30:05,669 --> 00:30:03,600 it's if if we had more experience in the 787 00:30:06,950 --> 00:30:05,679 permafrost environment that lisa was 788 00:30:08,549 --> 00:30:06,960 describing that's the kind of 789 00:30:11,669 --> 00:30:08,559 environment where 790 00:30:14,549 --> 00:30:11,679 as you freeze water with some salt in it 791 00:30:16,870 --> 00:30:14,559 you first precipitate out pure ice 792 00:30:18,630 --> 00:30:16,880 and that then causes the residual liquid 793 00:30:20,870 --> 00:30:18,640 to have more concentrated water and so 794 00:30:24,630 --> 00:30:20,880 the last liquid to freeze if it freezes 795 00:30:26,149 --> 00:30:24,640 at all is highly concentrated in salt 796 00:30:28,389 --> 00:30:26,159 uh 797 00:30:30,389 --> 00:30:28,399 there must be 798 00:30:32,070 --> 00:30:30,399 some some common substance that we're 799 00:30:33,590 --> 00:30:32,080 all familiar with that has a high 800 00:30:36,310 --> 00:30:33,600 concentration of salt so it's not coming 801 00:30:38,149 --> 00:30:36,320 to me what you put salt on your walkway 802 00:30:40,070 --> 00:30:38,159 okay so like the slush that would be 803 00:30:42,310 --> 00:30:40,080 left over maybe i mean i'm thinking of 804 00:30:44,710 --> 00:30:42,320 like buttermilk with the equivalent to 805 00:30:47,430 --> 00:30:44,720 salt you know like yeah 806 00:30:49,750 --> 00:30:47,440 so that makes sense right so 807 00:30:51,590 --> 00:30:49,760 this very salty water can be very 808 00:30:53,590 --> 00:30:51,600 different from water in that it is a 809 00:30:56,389 --> 00:30:53,600 higher in density and higher in 810 00:30:58,950 --> 00:30:56,399 viscosity so it is more like a syrup 811 00:31:00,870 --> 00:30:58,960 maybe in how it flows it could be 812 00:31:02,789 --> 00:31:00,880 we really don't know how salty this 813 00:31:03,509 --> 00:31:02,799 water is from these observations so this 814 00:31:07,990 --> 00:31:03,519 is 815 00:31:09,990 --> 00:31:08,000 different from pure water 816 00:31:11,509 --> 00:31:10,000 okay and i think the one personal 817 00:31:13,909 --> 00:31:11,519 experience you might have with this is 818 00:31:16,230 --> 00:31:13,919 when you're desperate to drink 819 00:31:19,029 --> 00:31:16,240 a liter bottle of soda but it's warm 820 00:31:21,190 --> 00:31:19,039 shove it in the freezer and it it you 821 00:31:23,830 --> 00:31:21,200 get a you get a block of ice in the 822 00:31:25,830 --> 00:31:23,840 middle of it and then this very sugar 823 00:31:28,149 --> 00:31:25,840 syrup around it where all the all the 824 00:31:30,070 --> 00:31:28,159 flavor and the goodies are 825 00:31:33,190 --> 00:31:30,080 that's because the water that freezes 826 00:31:34,950 --> 00:31:33,200 out is is quite pure ice and 827 00:31:36,710 --> 00:31:34,960 all of the other things the sugars and 828 00:31:38,470 --> 00:31:36,720 the salts are in the syrup and and we 829 00:31:40,149 --> 00:31:38,480 all know this from experience the whole 830 00:31:41,750 --> 00:31:40,159 thing doesn't freeze 831 00:31:44,950 --> 00:31:41,760 the ice freezes and then there's a 832 00:31:46,789 --> 00:31:44,960 remaining liquid brine in that 833 00:31:48,230 --> 00:31:46,799 in that plastic bottle and you just hope 834 00:31:49,750 --> 00:31:48,240 you didn't leave it there so long that 835 00:31:52,310 --> 00:31:49,760 the bottle 836 00:31:53,830 --> 00:31:52,320 expanded and blew up in your freezer and 837 00:31:57,110 --> 00:31:53,840 made a terrible mess 838 00:31:58,870 --> 00:31:57,120 okay so let's just imagine then that all 839 00:32:01,509 --> 00:31:58,880 of a sudden we can go to mars and live 840 00:32:03,190 --> 00:32:01,519 there like what do you do with what you 841 00:32:04,630 --> 00:32:03,200 have what i mean what do you do with 842 00:32:07,430 --> 00:32:04,640 this to make it 843 00:32:08,950 --> 00:32:07,440 usable is there an option is it is this 844 00:32:11,269 --> 00:32:08,960 something you do and you take samples 845 00:32:13,190 --> 00:32:11,279 back to the lab and go from there or and 846 00:32:14,630 --> 00:32:13,200 i don't really know 847 00:32:17,269 --> 00:32:14,640 how it goes from 848 00:32:19,509 --> 00:32:17,279 well we have plenty of pure water ice 849 00:32:21,990 --> 00:32:19,519 and that's that's water and it's more 850 00:32:23,350 --> 00:32:22,000 pure and the ice is easily accessible 851 00:32:25,029 --> 00:32:23,360 and uh 852 00:32:28,310 --> 00:32:25,039 you know that's that's very useful stuff 853 00:32:31,029 --> 00:32:28,320 so it might be that that's uh more 854 00:32:33,750 --> 00:32:31,039 usable than the brines for 855 00:32:36,710 --> 00:32:33,760 uh producing fuel and oxygen and 856 00:32:39,750 --> 00:32:36,720 drinking water and so forth 857 00:32:42,710 --> 00:32:39,760 but but i think the key here is 858 00:32:44,630 --> 00:32:42,720 we know mars has a lot of ice 859 00:32:46,789 --> 00:32:44,640 but this is the first 860 00:32:48,870 --> 00:32:46,799 time we've seen the potential 861 00:32:51,269 --> 00:32:48,880 for liquid 862 00:32:52,070 --> 00:32:51,279 water it might be salty water but it's 863 00:32:55,990 --> 00:32:52,080 still 864 00:32:58,149 --> 00:32:56,000 real the key here it's not that mars 865 00:32:59,110 --> 00:32:58,159 doesn't have a lot of ice but liquid 866 00:33:01,029 --> 00:32:59,120 water 867 00:33:04,149 --> 00:33:01,039 certainly to an organism 868 00:33:06,950 --> 00:33:04,159 is very very very different than ice and 869 00:33:09,430 --> 00:33:06,960 so that's i think the key 870 00:33:10,950 --> 00:33:09,440 right how people would use it that's a 871 00:33:12,950 --> 00:33:10,960 question i guess 872 00:33:14,710 --> 00:33:12,960 they might use it for their experiments 873 00:33:16,549 --> 00:33:14,720 yeah 874 00:33:18,389 --> 00:33:16,559 okay we have a questionnaire on the 875 00:33:30,310 --> 00:33:18,399 phone lines clara moskowitz from 876 00:33:32,870 --> 00:33:31,590 if not 877 00:33:34,710 --> 00:33:32,880 we'll see if we have another 878 00:33:37,430 --> 00:33:34,720 questionnaire come back to clara in a 879 00:33:40,950 --> 00:33:39,029 all right we're going to peter spots 880 00:33:51,350 --> 00:33:40,960 christian science monitor 881 00:33:51,360 --> 00:33:56,710 questions here in the auditorium 882 00:33:58,470 --> 00:33:57,509 no 883 00:34:01,669 --> 00:33:58,480 um 884 00:34:03,990 --> 00:34:01,679 well failing any other questions on the 885 00:34:06,630 --> 00:34:04,000 uh telephones uh did we have a follow-up 886 00:34:08,710 --> 00:34:06,640 oh we didn't have a follow-up all right 887 00:34:11,349 --> 00:34:08,720 since i have you all here um can someone 888 00:34:14,389 --> 00:34:11,359 just explain i guess in greater detail 889 00:34:19,349 --> 00:34:17,190 all right i can cover that one uh the 890 00:34:20,950 --> 00:34:19,359 gullies on mars are 891 00:34:22,310 --> 00:34:20,960 they were discovered a bit over 10 years 892 00:34:24,950 --> 00:34:22,320 ago they're 893 00:34:27,909 --> 00:34:24,960 these the classic form is an alcove 894 00:34:30,869 --> 00:34:27,919 channel and an apron of material 895 00:34:32,470 --> 00:34:30,879 somewhat similar to small alluvial fans 896 00:34:34,790 --> 00:34:32,480 on earth which are 897 00:34:37,990 --> 00:34:34,800 transported by water and so they've been 898 00:34:39,589 --> 00:34:38,000 uh taken as uh evidence for liquid water 899 00:34:40,310 --> 00:34:39,599 at some point there's been a lot of work 900 00:34:44,470 --> 00:34:40,320 in 901 00:34:46,869 --> 00:34:44,480 and how they might relate to possible 902 00:34:49,589 --> 00:34:46,879 snow deposits or variations in mars's 903 00:34:51,829 --> 00:34:49,599 orbit and the current activity we're 904 00:34:54,470 --> 00:34:51,839 seeing is in the winter when liquid 905 00:34:55,990 --> 00:34:54,480 water is less likely but 906 00:34:57,510 --> 00:34:56,000 exactly how that relates to the past 907 00:35:00,150 --> 00:34:57,520 history of gullies isn't completely 908 00:35:04,230 --> 00:35:02,069 okay thank you we have another question 909 00:35:05,750 --> 00:35:04,240 at ames research center in california 910 00:35:08,310 --> 00:35:05,760 please go ahead and identify yourself 911 00:35:08,320 --> 00:35:10,630 hey 912 00:35:14,870 --> 00:35:12,470 that's not the answer we wanted to uh 913 00:35:18,150 --> 00:35:14,880 the question we wanted to respond to 914 00:35:19,190 --> 00:35:18,160 um but let's see i guess if there are no 915 00:35:21,349 --> 00:35:19,200 other 916 00:35:23,589 --> 00:35:21,359 questions let me uh just remind 917 00:35:25,750 --> 00:35:23,599 everybody that all of this information 918 00:35:28,230 --> 00:35:25,760 about this and all the images are 919 00:35:32,230 --> 00:35:28,240 available on the nasa website at www 920 00:35:35,589 --> 00:35:34,069 mro 921 00:35:38,550 --> 00:35:35,599 we do have a question here in the 922 00:35:41,349 --> 00:35:38,560 auditorium in the back 923 00:35:43,190 --> 00:35:41,359 hi my name is jason callahan uh 924 00:35:44,550 --> 00:35:43,200 you mentioned that 925 00:35:46,310 --> 00:35:44,560 that a lot of study would need to be 926 00:35:48,630 --> 00:35:46,320 done to confirm or 927 00:35:52,310 --> 00:35:51,270 or uh rebut the the findings i was 928 00:35:54,069 --> 00:35:52,320 wondering 929 00:35:55,910 --> 00:35:54,079 what are the other plus 930 00:35:57,510 --> 00:35:55,920 possible or plausible explanations for 931 00:35:59,670 --> 00:35:57,520 what you're finding 932 00:36:01,670 --> 00:35:59,680 and what exactly would the process be 933 00:36:03,190 --> 00:36:01,680 how long do you think it would 934 00:36:04,710 --> 00:36:03,200 potentially take to to make this 935 00:36:06,470 --> 00:36:04,720 determination 936 00:36:07,910 --> 00:36:06,480 right so we've spent a lot of time the 937 00:36:10,950 --> 00:36:07,920 co-authors of this paper and trying to 938 00:36:13,990 --> 00:36:10,960 come up with alternate hypotheses 939 00:36:16,790 --> 00:36:14,000 it's clearly associated with uh warm 940 00:36:19,109 --> 00:36:16,800 temperatures from mars now just uh wrap 941 00:36:21,030 --> 00:36:19,119 end rapid temperature changes and and 942 00:36:23,670 --> 00:36:21,040 that can damage rock 943 00:36:26,230 --> 00:36:23,680 and cause bits of it to flake off 944 00:36:28,390 --> 00:36:26,240 but that's a slow process and why this 945 00:36:31,109 --> 00:36:28,400 occurs in only some places and not 946 00:36:33,190 --> 00:36:31,119 others is puzzling 947 00:36:36,310 --> 00:36:33,200 and certainly the incremental growth and 948 00:36:38,390 --> 00:36:36,320 so forth none of that quite makes sense 949 00:36:39,990 --> 00:36:38,400 another possibility is well there's dust 950 00:36:42,069 --> 00:36:40,000 over most of mars these are relatively 951 00:36:43,829 --> 00:36:42,079 dust free areas but there's some dust 952 00:36:47,270 --> 00:36:43,839 everywhere if you remove dust it gets 953 00:36:50,230 --> 00:36:47,280 darker and you add dust it gets brighter 954 00:36:52,230 --> 00:36:50,240 the problem with that is that we don't 955 00:36:53,510 --> 00:36:52,240 we don't we've seen dust avalanches 956 00:36:55,109 --> 00:36:53,520 elsewhere we know what they look like 957 00:36:57,510 --> 00:36:55,119 they don't share these characteristics 958 00:36:59,589 --> 00:36:57,520 they don't have seasonality 959 00:37:01,910 --> 00:36:59,599 it does cause a color change when you 960 00:37:03,829 --> 00:37:01,920 move dust from rocky ground we don't see 961 00:37:05,990 --> 00:37:03,839 that color change 962 00:37:07,910 --> 00:37:06,000 here we don't understand why would have 963 00:37:09,910 --> 00:37:07,920 this latitudinal distribution and 964 00:37:11,589 --> 00:37:09,920 seasonality and so forth if that was the 965 00:37:13,510 --> 00:37:11,599 case 966 00:37:16,550 --> 00:37:13,520 another idea that might be a little more 967 00:37:19,270 --> 00:37:16,560 promising is that maybe maybe this is 968 00:37:21,510 --> 00:37:19,280 activity induced by removing water it 969 00:37:23,510 --> 00:37:21,520 gets warm and you sub there's very thin 970 00:37:25,670 --> 00:37:23,520 films of water that can coat grains and 971 00:37:27,910 --> 00:37:25,680 it makes them sticky this was something 972 00:37:29,270 --> 00:37:27,920 that the phoenix mission people know 973 00:37:31,109 --> 00:37:29,280 about very well where they couldn't get 974 00:37:32,790 --> 00:37:31,119 their sample out of their scoop and into 975 00:37:33,990 --> 00:37:32,800 their instruments because it was so 976 00:37:36,310 --> 00:37:34,000 sticky 977 00:37:39,109 --> 00:37:36,320 so maybe when it warms up that removes 978 00:37:40,870 --> 00:37:39,119 that stickiness and then causes it to 979 00:37:42,630 --> 00:37:40,880 you know dry grains to tumble down the 980 00:37:43,829 --> 00:37:42,640 slope 981 00:37:46,230 --> 00:37:43,839 but again 982 00:37:48,470 --> 00:37:46,240 why do why are they only certain places 983 00:37:50,790 --> 00:37:48,480 why only the mid-latitudes 984 00:37:53,430 --> 00:37:50,800 why not the northern hemisphere 985 00:37:56,230 --> 00:37:53,440 uh you know these these these questions 986 00:37:57,910 --> 00:37:56,240 the whole story doesn't fit together but 987 00:37:59,750 --> 00:37:57,920 so we haven't been able to come up with 988 00:38:01,109 --> 00:37:59,760 an alternate that we believe but but 989 00:38:02,790 --> 00:38:01,119 there may be people out there that are 990 00:38:04,470 --> 00:38:02,800 more clever than us and and it's 991 00:38:05,349 --> 00:38:04,480 definitely worthwhile to keep thinking 992 00:38:09,589 --> 00:38:05,359 about 993 00:38:14,069 --> 00:38:12,390 okay we'll try the phone bridge again uh 994 00:38:15,990 --> 00:38:14,079 we have a caller from san francisco 995 00:38:17,589 --> 00:38:16,000 david perlman from the san francisco 996 00:38:20,630 --> 00:38:17,599 chronicle 997 00:38:24,390 --> 00:38:21,670 you know hi 998 00:38:25,349 --> 00:38:24,400 i have just a quick question 999 00:38:29,190 --> 00:38:25,359 in 1000 00:38:30,470 --> 00:38:29,200 comparison with the evidence from 1001 00:38:32,390 --> 00:38:30,480 phoenix 1002 00:38:35,349 --> 00:38:32,400 and the evidence from 1003 00:38:40,310 --> 00:38:35,359 uh mars global surveyor 1004 00:38:41,910 --> 00:38:40,320 how do you rate this uh as to 1005 00:38:44,630 --> 00:38:41,920 convincing 1006 00:38:46,390 --> 00:38:44,640 evidence of the possibility and i'll say 1007 00:38:49,430 --> 00:38:46,400 possibility of water 1008 00:38:51,670 --> 00:38:49,440 you've had a lot of uh observations of 1009 00:38:54,230 --> 00:38:51,680 water snow ice 1010 00:38:56,069 --> 00:38:54,240 from previous missions and how does this 1011 00:38:59,430 --> 00:38:56,079 stack up in terms of 1012 00:39:00,470 --> 00:38:59,440 it's uh improving the possibility of of 1013 00:39:02,870 --> 00:39:00,480 water 1014 00:39:05,589 --> 00:39:02,880 and i'd like to follow up with uh lisa 1015 00:39:07,430 --> 00:39:05,599 for a quick question if i may 1016 00:39:09,510 --> 00:39:07,440 okay let me just remind people quickly 1017 00:39:12,150 --> 00:39:09,520 of a phoenix mission result where there 1018 00:39:13,109 --> 00:39:12,160 were apparent droplets that formed on 1019 00:39:22,230 --> 00:39:13,119 the 1020 00:39:24,470 --> 00:39:22,240 particularly pick up salt that 1021 00:39:27,349 --> 00:39:24,480 absorbs water from the atmosphere and so 1022 00:39:29,349 --> 00:39:27,359 it a plausible explanation is that the 1023 00:39:30,950 --> 00:39:29,359 salt that was kicked up from landing on 1024 00:39:32,950 --> 00:39:30,960 the legs absorbed water from the 1025 00:39:34,870 --> 00:39:32,960 atmosphere and made droplets 1026 00:39:37,030 --> 00:39:34,880 and if that's the case there should be 1027 00:39:39,430 --> 00:39:37,040 you know droplets of water that form in 1028 00:39:41,270 --> 00:39:39,440 the regolith on the ground as well at 1029 00:39:43,589 --> 00:39:41,280 the phoenix site 1030 00:39:45,109 --> 00:39:43,599 so uh i don't know if that's more or 1031 00:39:47,510 --> 00:39:45,119 less plausible than what we're saying 1032 00:39:49,349 --> 00:39:47,520 but that's extremely cold water so what 1033 00:39:51,829 --> 00:39:49,359 we're seeing is at least warmer water 1034 00:39:53,109 --> 00:39:51,839 that's that's more friendly to possible 1035 00:39:55,829 --> 00:39:53,119 uh life 1036 00:39:57,349 --> 00:39:55,839 and it's flowing so it's different i'm 1037 00:39:59,589 --> 00:39:57,359 not going to rate which one is more 1038 00:40:01,589 --> 00:39:59,599 likely to be water 1039 00:40:03,349 --> 00:40:01,599 for mgs maybe 1040 00:40:05,109 --> 00:40:03,359 maybe phil would 1041 00:40:07,349 --> 00:40:05,119 talk about that 1042 00:40:09,670 --> 00:40:07,359 um again dave it's hard to it's hard to 1043 00:40:12,069 --> 00:40:09,680 rate these i i think for me 1044 00:40:13,030 --> 00:40:12,079 the story has been growing 1045 00:40:15,030 --> 00:40:13,040 uh 1046 00:40:17,829 --> 00:40:15,040 we've found water in increasing number 1047 00:40:20,950 --> 00:40:17,839 of places and increasing abundances 1048 00:40:23,190 --> 00:40:20,960 and and other than the the observations 1049 00:40:25,990 --> 00:40:23,200 that um alfred just referred to which 1050 00:40:27,829 --> 00:40:26,000 were extremely cold polar regions 1051 00:40:29,349 --> 00:40:27,839 i think this is the best evidence we 1052 00:40:33,990 --> 00:40:29,359 have to date 1053 00:40:37,430 --> 00:40:34,000 of a liquid water occurring today 1054 00:40:39,670 --> 00:40:37,440 on mars there's again evidence 1055 00:40:42,069 --> 00:40:39,680 these other features may have formed by 1056 00:40:45,829 --> 00:40:42,079 liquid water in the past but as far as 1057 00:40:47,990 --> 00:40:45,839 liquid water to liquid water today the 1058 00:40:49,430 --> 00:40:48,000 places where it's warm enough to stay 1059 00:40:52,470 --> 00:40:49,440 liquid for a while i think this is the 1060 00:40:54,069 --> 00:40:52,480 best evidence we have 1061 00:40:58,309 --> 00:40:54,079 okay david and your follow-up question 1062 00:41:03,670 --> 00:41:01,670 yeah i couldn't quite understand uh 1063 00:41:05,829 --> 00:41:03,680 about the 1064 00:41:09,270 --> 00:41:05,839 how an organism 1065 00:41:12,550 --> 00:41:09,280 in a subsurface a sub uh 1066 00:41:14,950 --> 00:41:12,560 how did you phrase it i've forgotten now 1067 00:41:18,390 --> 00:41:14,960 beneath the permafrost where you might 1068 00:41:21,109 --> 00:41:18,400 have liquid water beneath permafrost uh 1069 00:41:24,390 --> 00:41:21,119 you indicated that there they the 1070 00:41:26,470 --> 00:41:24,400 organisms like that could uh proliferate 1071 00:41:28,710 --> 00:41:26,480 uh but if there's no 1072 00:41:31,270 --> 00:41:28,720 light of any kind i recognize of course 1073 00:41:33,270 --> 00:41:31,280 that extremophiles have been found with 1074 00:41:35,109 --> 00:41:33,280 no visible light apparent 1075 00:41:37,270 --> 00:41:35,119 but could you explain a little bit how 1076 00:41:38,390 --> 00:41:37,280 an organism might 1077 00:41:43,270 --> 00:41:38,400 grow 1078 00:41:45,109 --> 00:41:43,280 beneath a a solid surface of permafrost 1079 00:41:47,030 --> 00:41:45,119 i think we would assume it would grow in 1080 00:41:49,109 --> 00:41:47,040 the same way that that happens on earth 1081 00:41:51,270 --> 00:41:49,119 where we see life in the deep subsurface 1082 00:41:53,829 --> 00:41:51,280 that is utilizing some other source of 1083 00:41:55,670 --> 00:41:53,839 energy usually a chemical gradient where 1084 00:41:57,670 --> 00:41:55,680 the organism is either able to do an 1085 00:41:59,589 --> 00:41:57,680 oxidation or a reduction taking 1086 00:42:01,670 --> 00:41:59,599 advantage of 1087 00:42:04,150 --> 00:42:01,680 dissolved constituents in brines and 1088 00:42:05,829 --> 00:42:04,160 mineral surfaces certainly this 1089 00:42:06,950 --> 00:42:05,839 community of organisms that i've been 1090 00:42:08,950 --> 00:42:06,960 part of 1091 00:42:11,910 --> 00:42:08,960 discovering and looking at 1092 00:42:14,390 --> 00:42:11,920 in the deep groundwater in south africa 1093 00:42:18,069 --> 00:42:14,400 those are sulfate reducers sulfate 1094 00:42:20,710 --> 00:42:18,079 reduction is a common process in anoxic 1095 00:42:22,870 --> 00:42:20,720 parts of the surface ocean as well and 1096 00:42:25,430 --> 00:42:22,880 given the amount of sulfur and in 1097 00:42:27,589 --> 00:42:25,440 particular sulfate that we now know is 1098 00:42:30,309 --> 00:42:27,599 present on mars i think a sulfur-based 1099 00:42:32,630 --> 00:42:30,319 metabolism would be a very uh very 1100 00:42:34,309 --> 00:42:32,640 reasonable one to anticipate 1101 00:42:36,309 --> 00:42:34,319 the way in which it would communicate 1102 00:42:39,510 --> 00:42:36,319 with the surface environment and 1103 00:42:42,870 --> 00:42:39,520 possibly take advantage of 1104 00:42:45,910 --> 00:42:42,880 seasonal access to the surface world 1105 00:42:49,030 --> 00:42:45,920 would be if there was a fracture network 1106 00:42:50,950 --> 00:42:49,040 that created a conduit that extended 1107 00:42:54,470 --> 00:42:50,960 through the permafrost on earth we would 1108 00:42:56,309 --> 00:42:54,480 call that italic which means there are 1109 00:42:59,270 --> 00:42:56,319 are fluids that because of their 1110 00:43:02,309 --> 00:42:59,280 saltiness actually create a column of 1111 00:43:04,630 --> 00:43:02,319 unfrozen ground through the permafrost 1112 00:43:06,710 --> 00:43:04,640 now again we don't have any evidence for 1113 00:43:08,870 --> 00:43:06,720 that yet on mars but when we look at 1114 00:43:11,109 --> 00:43:08,880 analog environments with very cold very 1115 00:43:12,790 --> 00:43:11,119 thick permafrost on earth 1116 00:43:13,510 --> 00:43:12,800 those are the kind of features we see 1117 00:43:16,150 --> 00:43:13,520 and 1118 00:43:19,190 --> 00:43:16,160 if there were to have been 1119 00:43:22,309 --> 00:43:19,200 um life on mars and if it evolved and 1120 00:43:23,589 --> 00:43:22,319 adapted to this permafrost world i i 1121 00:43:25,349 --> 00:43:23,599 think those are 1122 00:43:27,589 --> 00:43:25,359 reasonable things that we could go look 1123 00:43:29,670 --> 00:43:27,599 for 1124 00:43:31,589 --> 00:43:29,680 all right we have another question on 1125 00:43:33,829 --> 00:43:31,599 the phone lines clara moskowitz from 1126 00:43:38,470 --> 00:43:33,839 space.com tried clara again please go 1127 00:43:43,109 --> 00:43:40,950 yes thanks very much um i understand 1128 00:43:45,589 --> 00:43:43,119 that if this water exists at all it only 1129 00:43:47,510 --> 00:43:45,599 exists seasonally so could you talk a 1130 00:43:49,670 --> 00:43:47,520 little bit more about what type of 1131 00:43:51,430 --> 00:43:49,680 organisms would be able to survive that 1132 00:43:53,510 --> 00:43:51,440 kind of change and what would happen to 1133 00:43:56,230 --> 00:43:53,520 the organisms when the water wasn't 1134 00:43:56,240 --> 00:43:59,270 you want me to take that one 1135 00:44:04,550 --> 00:44:02,550 again this is very speculative because 1136 00:44:06,790 --> 00:44:04,560 we really have no idea whether or not 1137 00:44:09,109 --> 00:44:06,800 there are extant organisms on mars or if 1138 00:44:11,270 --> 00:44:09,119 there ever was life on mars but what we 1139 00:44:14,390 --> 00:44:11,280 see on earth in that kind of a setting 1140 00:44:16,870 --> 00:44:14,400 is that if there are cryo pegs 1141 00:44:19,829 --> 00:44:16,880 cold salty waters that never freeze 1142 00:44:23,190 --> 00:44:19,839 despite the cold surrounding frozen 1143 00:44:25,910 --> 00:44:23,200 ground then they simply remain 1144 00:44:28,150 --> 00:44:25,920 active at all times although at lower 1145 00:44:30,790 --> 00:44:28,160 metabolic rates when uh when the coldest 1146 00:44:33,349 --> 00:44:30,800 temperatures occur if the if the 1147 00:44:35,109 --> 00:44:33,359 environment is one in which it's liquid 1148 00:44:37,670 --> 00:44:35,119 seasonally but 1149 00:44:39,430 --> 00:44:37,680 pretty much freezes up solid at other 1150 00:44:41,349 --> 00:44:39,440 times a year and that would have to be 1151 00:44:43,510 --> 00:44:41,359 an organism that could go into a dormant 1152 00:44:47,589 --> 00:44:43,520 state or could could go into a resting 1153 00:44:50,069 --> 00:44:47,599 state and just uh patiently hang out on 1154 00:44:51,589 --> 00:44:50,079 near the surface and until spring comes 1155 00:44:53,510 --> 00:44:51,599 around again 1156 00:44:55,589 --> 00:44:53,520 this is a strategy that we see many 1157 00:44:57,990 --> 00:44:55,599 organisms on earth using to get through 1158 00:45:00,470 --> 00:44:58,000 either long dry spells or to get through 1159 00:45:02,870 --> 00:45:00,480 long cold spells so if there were to be 1160 00:45:04,550 --> 00:45:02,880 evolving organisms on mars i don't see 1161 00:45:06,390 --> 00:45:04,560 any reason why they couldn't uh couldn't 1162 00:45:09,510 --> 00:45:06,400 adapt to that kind of 1163 00:45:10,870 --> 00:45:09,520 seasonally available very brief access 1164 00:45:13,349 --> 00:45:10,880 to resources 1165 00:45:17,670 --> 00:45:13,359 you you bloom quickly you do what you 1166 00:45:21,349 --> 00:45:19,109 all right we have another question uh 1167 00:45:25,910 --> 00:45:21,359 peter spots christian science monitor on 1168 00:45:29,030 --> 00:45:27,510 yeah thank you very much 1169 00:45:31,430 --> 00:45:29,040 actually i guess it's a trivia question 1170 00:45:33,030 --> 00:45:31,440 but since you were able to do this uh 1171 00:45:35,270 --> 00:45:33,040 observe these repeatedly are there any 1172 00:45:37,190 --> 00:45:35,280 even back of the envelope estimates 1173 00:45:40,069 --> 00:45:37,200 for let's say newton crater and the 1174 00:45:42,390 --> 00:45:40,079 amount of water uh that was flowing over 1175 00:45:44,150 --> 00:45:42,400 these periods uh particularly since it 1176 00:45:45,109 --> 00:45:44,160 seems over these long seasons it's not 1177 00:45:46,950 --> 00:45:45,119 you know these things are kind of 1178 00:45:48,790 --> 00:45:46,960 renewing and extending themselves you 1179 00:45:51,190 --> 00:45:48,800 have a kind of a sense for how much 1180 00:45:53,430 --> 00:45:51,200 water we're talking about how much fluid 1181 00:45:54,790 --> 00:45:53,440 uh yeah well i can you have to make 1182 00:45:56,710 --> 00:45:54,800 assumptions here we don't really know 1183 00:45:59,030 --> 00:45:56,720 the mechanism and in particular we don't 1184 00:46:01,349 --> 00:45:59,040 know whether this is really a flow of 1185 00:46:02,790 --> 00:46:01,359 water for the most part or whether it's 1186 00:46:05,190 --> 00:46:02,800 just a matter of 1187 00:46:08,390 --> 00:46:05,200 wetting a boundary layer and you have a 1188 00:46:09,910 --> 00:46:08,400 debris flow flowing on a thin film of 1189 00:46:12,470 --> 00:46:09,920 water 1190 00:46:14,390 --> 00:46:12,480 so estimates could vary but if if it's a 1191 00:46:17,270 --> 00:46:14,400 flow of water there were some laboratory 1192 00:46:19,349 --> 00:46:17,280 experiments done in 1193 00:46:21,910 --> 00:46:19,359 in the united kingdom recently published 1194 00:46:23,910 --> 00:46:21,920 by conway at all in which they they 1195 00:46:25,990 --> 00:46:23,920 poured water on a slope 1196 00:46:27,670 --> 00:46:26,000 it mars atmospheric pressure and 1197 00:46:29,910 --> 00:46:27,680 temperature conditions pure water and 1198 00:46:31,190 --> 00:46:29,920 made features that look look somewhat 1199 00:46:33,349 --> 00:46:31,200 like these but 1200 00:46:35,670 --> 00:46:33,359 just scaling from that 1201 00:46:38,870 --> 00:46:35,680 we're talking about for a typical flow 1202 00:46:41,670 --> 00:46:38,880 something like 100 liters of water 1203 00:46:44,230 --> 00:46:41,680 so 25 gallons so that's a pretty modest 1204 00:46:47,589 --> 00:46:44,240 amount but if there's a thousand of them 1205 00:46:49,910 --> 00:46:47,599 uh then then that starts to amount to 1206 00:46:52,950 --> 00:46:49,920 multiple swimming pools worth of water 1207 00:46:55,109 --> 00:46:52,960 the sort of that that magnitude it's 1208 00:46:57,430 --> 00:46:55,119 this is a lot less water than than you 1209 00:47:00,309 --> 00:46:57,440 need to to explain the gullies if those 1210 00:47:02,069 --> 00:47:00,319 form by water for example and it's it's 1211 00:47:03,829 --> 00:47:02,079 a relatively small amount of water 1212 00:47:06,710 --> 00:47:03,839 relative to the total inventory that we 1213 00:47:08,230 --> 00:47:06,720 know of on the planet 1214 00:47:10,790 --> 00:47:08,240 all right the next question on the phone 1215 00:47:16,150 --> 00:47:10,800 lines anne ryman from the arizona 1216 00:47:19,750 --> 00:47:17,829 thank you i wondered if you could tell 1217 00:47:22,309 --> 00:47:19,760 us a little bit more about this newton 1218 00:47:24,870 --> 00:47:22,319 crater what it's like there and then how 1219 00:47:26,630 --> 00:47:24,880 close are any of the other landed 1220 00:47:29,910 --> 00:47:26,640 missions to this crater like the you 1221 00:47:33,109 --> 00:47:29,920 know the rovers or um when curiosity 1222 00:47:35,510 --> 00:47:33,119 lands how how far away would it be from 1223 00:47:37,349 --> 00:47:35,520 this newton crater site thank you okay 1224 00:47:38,870 --> 00:47:37,359 well the newton crater site is uh i 1225 00:47:40,630 --> 00:47:38,880 think the opposite side of mars but 1226 00:47:42,870 --> 00:47:40,640 there are multiple sites that the one 1227 00:47:43,829 --> 00:47:42,880 closest to gale crater is horowitz 1228 00:47:45,750 --> 00:47:43,839 crater 1229 00:47:47,910 --> 00:47:45,760 named after norman horowitz of the 1230 00:47:51,589 --> 00:47:47,920 viking biology experiment fame 1231 00:47:53,510 --> 00:47:51,599 appropriately that's at 32 south gale is 1232 00:47:56,390 --> 00:47:53,520 a few degrees south they're something 1233 00:47:58,710 --> 00:47:56,400 like 2 000 kilometers apart so 1234 00:48:00,549 --> 00:47:58,720 that's relatively close but still a long 1235 00:48:01,750 --> 00:48:00,559 ways away 1236 00:48:03,910 --> 00:48:01,760 uh 1237 00:48:07,349 --> 00:48:03,920 you asked what it's what it's like at 1238 00:48:09,829 --> 00:48:07,359 newton crater and 1239 00:48:11,270 --> 00:48:09,839 not quite sure what to say beyond what i 1240 00:48:17,190 --> 00:48:11,280 showed you previously could you clarify 1241 00:48:20,950 --> 00:48:18,870 i'm just curious like how much we know 1242 00:48:22,870 --> 00:48:20,960 about it um just if there's any sort of 1243 00:48:25,510 --> 00:48:22,880 description of it that people would find 1244 00:48:30,390 --> 00:48:28,470 well it's a relatively young crater it 1245 00:48:33,109 --> 00:48:30,400 doesn't have a name now we need to 1246 00:48:35,670 --> 00:48:33,119 submit to iu names for the the craters 1247 00:48:37,349 --> 00:48:35,680 that we're making famous here 1248 00:48:39,349 --> 00:48:37,359 but it's a relatively well preserved 10 1249 00:48:42,150 --> 00:48:39,359 kilometer diameter crater 1250 00:48:43,990 --> 00:48:42,160 uh the crater itself is is probably a 1251 00:48:47,589 --> 00:48:44,000 few hundred million years old just 1252 00:48:49,589 --> 00:48:47,599 judging from its state of preservation 1253 00:48:51,030 --> 00:48:49,599 it has steep crater walls because it's 1254 00:48:53,910 --> 00:48:51,040 relatively young 1255 00:48:56,870 --> 00:48:53,920 it's still well preserved and has steep 1256 00:48:58,230 --> 00:48:56,880 crater walls it exposed bedrock around 1257 00:49:00,790 --> 00:48:58,240 the rim 1258 00:49:03,270 --> 00:49:00,800 it's got gullies as colin showed on on 1259 00:49:04,950 --> 00:49:03,280 the north side and fine channels around 1260 00:49:06,069 --> 00:49:04,960 the rest of the crater that may or may 1261 00:49:08,630 --> 00:49:06,079 not be 1262 00:49:10,950 --> 00:49:08,640 related to these flow features 1263 00:49:13,109 --> 00:49:10,960 these flow features also seem to emanate 1264 00:49:16,309 --> 00:49:13,119 from bedrock which is eroded back into 1265 00:49:18,150 --> 00:49:16,319 sort of a sapping like morphology 1266 00:49:20,230 --> 00:49:18,160 so that that site 1267 00:49:21,990 --> 00:49:20,240 looks more like water for that reason 1268 00:49:23,829 --> 00:49:22,000 but again we don't really know cause and 1269 00:49:25,750 --> 00:49:23,839 effect here maybe that formed first 1270 00:49:27,829 --> 00:49:25,760 before these slope features started 1271 00:49:30,390 --> 00:49:27,839 forming 1272 00:49:32,069 --> 00:49:30,400 okay we have a question back at nasa's 1273 00:49:33,349 --> 00:49:32,079 ames research center in california 1274 00:49:37,109 --> 00:49:33,359 please go ahead state your name and 1275 00:49:42,710 --> 00:49:40,390 uh douglas messier from parabolicarc.com 1276 00:49:45,270 --> 00:49:42,720 i was wondering about the 1277 00:49:46,870 --> 00:49:45,280 mechanism is are the organisms that 1278 00:49:47,829 --> 00:49:46,880 might be 1279 00:49:50,069 --> 00:49:47,839 in 1280 00:49:51,750 --> 00:49:50,079 water under the soil protected from the 1281 00:49:53,829 --> 00:49:51,760 radiation and what happens if they 1282 00:49:55,670 --> 00:49:53,839 outflow and get exposed suddenly to 1283 00:49:58,230 --> 00:49:55,680 surface radiation 1284 00:50:00,230 --> 00:49:58,240 or the organisms 1285 00:50:03,030 --> 00:50:00,240 might they be adapted to dealing with 1286 00:50:05,030 --> 00:50:03,040 that level of radiation 1287 00:50:07,190 --> 00:50:05,040 i think we have to assume if they're if 1288 00:50:08,950 --> 00:50:07,200 there are organisms on mars that they're 1289 00:50:10,950 --> 00:50:08,960 highly adapted 1290 00:50:13,349 --> 00:50:10,960 and capable and one of the things they'd 1291 00:50:15,430 --> 00:50:13,359 have to be able to tolerate is is 1292 00:50:20,630 --> 00:50:15,440 exposure to 1293 00:50:23,349 --> 00:50:20,640 radiation environment and one of the 1294 00:50:25,430 --> 00:50:23,359 nice coincidences is of course that iron 1295 00:50:27,270 --> 00:50:25,440 oxides give are a pretty darn good 1296 00:50:29,030 --> 00:50:27,280 sunscreen so one 1297 00:50:31,190 --> 00:50:29,040 actually might envision that they've 1298 00:50:34,150 --> 00:50:31,200 they've found a way to be sticky enough 1299 00:50:36,549 --> 00:50:34,160 that the iron oxide in the surface dust 1300 00:50:38,790 --> 00:50:36,559 adheres to them and that puts them under 1301 00:50:42,230 --> 00:50:38,800 a little sunbrella and keeps them from 1302 00:50:46,950 --> 00:50:44,710 okay that's all the questions we have 1303 00:50:48,630 --> 00:50:46,960 again as a reminder all these images 1304 00:50:50,069 --> 00:50:48,640 you've seen today a lot more information 1305 00:50:55,030 --> 00:50:50,079 about mro 1306 00:50:57,990 --> 00:50:56,309 mro