1 00:00:05,990 --> 00:00:04,340 like to talk about exploring Mars for 2 00:00:09,020 --> 00:00:06,000 evidence of habitable environments and 3 00:00:11,540 --> 00:00:09,030 life and it really is a fascinating 4 00:00:14,720 --> 00:00:11,550 story that goes back more than a century 5 00:00:18,080 --> 00:00:14,730 of course we have basic questions about 6 00:00:19,910 --> 00:00:18,090 what Mars the planet is all about but in 7 00:00:22,220 --> 00:00:19,920 many ways the best way to address these 8 00:00:24,170 --> 00:00:22,230 questions is to address them in parallel 9 00:00:27,320 --> 00:00:24,180 with a question of searching for life 10 00:00:30,830 --> 00:00:27,330 itself and so in that vein I'd like to 11 00:00:33,080 --> 00:00:30,840 review you know Mars exploration over 12 00:00:34,970 --> 00:00:33,090 the past several decades and how we're 13 00:00:36,950 --> 00:00:34,980 getting ever better at answering this 14 00:00:40,310 --> 00:00:36,960 question of is there a second example of 15 00:00:41,900 --> 00:00:40,320 life in our solar system and you can see 16 00:00:44,959 --> 00:00:41,910 from the two graphics on this first 17 00:00:46,819 --> 00:00:44,969 slide that early Mars might have been 18 00:00:48,380 --> 00:00:46,829 quite a different place than Mars today 19 00:00:50,029 --> 00:00:48,390 and of course that adds to the 20 00:00:53,510 --> 00:00:50,039 excitement as well as the promise that 21 00:00:56,630 --> 00:00:53,520 indeed life once existed there the talk 22 00:00:58,069 --> 00:00:56,640 outline then is really just to get a 23 00:01:00,110 --> 00:00:58,079 start to compare Mars and the earth 24 00:01:03,200 --> 00:01:00,120 earth is obviously the one place where 25 00:01:05,030 --> 00:01:03,210 we know life exists today and therefore 26 00:01:06,740 --> 00:01:05,040 the characteristics of shares of Mars 27 00:01:12,039 --> 00:01:06,750 are quite relevant to the search for 28 00:01:14,960 --> 00:01:12,049 Mars life the Mars exploration Rovers 29 00:01:16,789 --> 00:01:14,970 recent exploration of Mars made several 30 00:01:17,719 --> 00:01:16,799 key discoveries that are quite important 31 00:01:19,190 --> 00:01:17,729 for the search for habitable 32 00:01:21,590 --> 00:01:19,200 environments in life and so I'd like 33 00:01:23,620 --> 00:01:21,600 briefly to review some of the key 34 00:01:27,830 --> 00:01:23,630 relevant discoveries that they've made 35 00:01:30,050 --> 00:01:27,840 this is being taped in early 2012 and at 36 00:01:32,109 --> 00:01:30,060 this point we look forward to the 37 00:01:36,020 --> 00:01:32,119 Curiosity rover which will land on 38 00:01:38,660 --> 00:01:36,030 August of 2012 and it represents really 39 00:01:42,020 --> 00:01:38,670 an extension of this long-term effort to 40 00:01:44,450 --> 00:01:42,030 explore Mars and search for life and 41 00:01:47,090 --> 00:01:44,460 this is put in sort of a lecture format 42 00:01:48,560 --> 00:01:47,100 so I've included periodically some 43 00:01:51,469 --> 00:01:48,570 questions after each of the sections 44 00:01:55,100 --> 00:01:51,479 that students might want to address and 45 00:01:57,050 --> 00:01:55,110 use it to test their comprehension the 46 00:02:00,830 --> 00:01:57,060 next slide then starts the story at 47 00:02:02,959 --> 00:02:00,840 least this lecture with the sort of 48 00:02:05,359 --> 00:02:02,969 knowledge level of Mars some hundred 49 00:02:07,819 --> 00:02:05,369 years ago a very famous astronomer 50 00:02:10,449 --> 00:02:07,829 percival lowell really was quite 51 00:02:13,610 --> 00:02:10,459 fascinated with mars and he had a 52 00:02:17,470 --> 00:02:13,620 state-of-the-art telescope at that time 53 00:02:20,180 --> 00:02:17,480 in his Arizona observatory and he 54 00:02:22,820 --> 00:02:20,190 created this map that you see here of 55 00:02:24,920 --> 00:02:22,830 Mars showing these linear features sort 56 00:02:27,680 --> 00:02:24,930 of connecting nodes these little black 57 00:02:30,050 --> 00:02:27,690 dots that you see and he became quite 58 00:02:32,780 --> 00:02:30,060 excited by you know these features that 59 00:02:34,750 --> 00:02:32,790 he perceived indicating that perhaps 60 00:02:38,229 --> 00:02:34,760 this was evidence of an advanced 61 00:02:40,970 --> 00:02:38,239 intelligent life one that was perhaps 62 00:02:42,949 --> 00:02:40,980 under stress because of the very heap 63 00:02:45,259 --> 00:02:42,959 what he would describe as a very dry 64 00:02:47,390 --> 00:02:45,269 arid environment on Mars and that these 65 00:02:49,940 --> 00:02:47,400 straight lines were perhaps canals that 66 00:02:51,800 --> 00:02:49,950 were connecting sources of water to 67 00:02:54,530 --> 00:02:51,810 agricultural fields and that perhaps 68 00:02:56,089 --> 00:02:54,540 these nodes represented cities well you 69 00:02:59,380 --> 00:02:56,099 can imagine that this created quite a 70 00:03:02,380 --> 00:02:59,390 stir in the public at that time and 71 00:03:04,789 --> 00:03:02,390 therefore heightened the interest and 72 00:03:07,309 --> 00:03:04,799 certainly contributed to the interest in 73 00:03:09,740 --> 00:03:07,319 Mars and Mars exploration in the years 74 00:03:12,589 --> 00:03:09,750 that followed but I also like to start 75 00:03:14,390 --> 00:03:12,599 here just to remind us all of just what 76 00:03:16,130 --> 00:03:14,400 our state of knowledge was just a little 77 00:03:17,539 --> 00:03:16,140 over a hundred years ago and compare 78 00:03:19,849 --> 00:03:17,549 that to what you're going to hear next 79 00:03:21,920 --> 00:03:19,859 it's a remarkable statement about the 80 00:03:27,129 --> 00:03:21,930 achievements of the 20th century and now 81 00:03:31,670 --> 00:03:27,139 moving into the 21st century based on 82 00:03:34,220 --> 00:03:31,680 lolz accounts and also the novelist's 83 00:03:36,500 --> 00:03:34,230 and others of the time there was this 84 00:03:40,190 --> 00:03:36,510 perception of these civilizations having 85 00:03:43,099 --> 00:03:40,200 these cities and these canals and you 86 00:03:44,780 --> 00:03:43,109 know hg wells you know wrote a a major 87 00:03:48,470 --> 00:03:44,790 piece about this about these 88 00:03:51,140 --> 00:03:48,480 civilizations and orson welles in 1938 89 00:03:53,659 --> 00:03:51,150 actually you know did a radio broadcast 90 00:03:55,069 --> 00:03:53,669 of Martians attacking the earth and of 91 00:03:57,229 --> 00:03:55,079 course it was meant to be entertainment 92 00:03:59,930 --> 00:03:57,239 it was meant to be a sort of science 93 00:04:02,289 --> 00:03:59,940 fiction but the public at that time took 94 00:04:06,379 --> 00:04:02,299 it quite seriously there was a lot of 95 00:04:09,619 --> 00:04:06,389 you know public angst about this and it 96 00:04:11,569 --> 00:04:09,629 just Illustrated it even in 1938 people 97 00:04:13,789 --> 00:04:11,579 were quite prepared to believe that this 98 00:04:15,890 --> 00:04:13,799 was this picture might represent Mars 99 00:04:18,949 --> 00:04:15,900 and that we were potentially under 100 00:04:20,839 --> 00:04:18,959 threat of invading forces and again this 101 00:04:22,730 --> 00:04:20,849 underscores the first of all the 102 00:04:26,930 --> 00:04:22,740 perception of what Mars environment was 103 00:04:27,270 --> 00:04:26,940 like at that time 1938 and also just our 104 00:04:29,250 --> 00:04:27,280 real 105 00:04:33,450 --> 00:04:29,260 rudimentary knowledge about that planet 106 00:04:35,879 --> 00:04:33,460 and of course as observations got better 107 00:04:38,580 --> 00:04:35,889 through the 20th century astronomical 108 00:04:40,530 --> 00:04:38,590 observations it became clear that the 109 00:04:43,140 --> 00:04:40,540 atmosphere of Mars was much thinner than 110 00:04:45,180 --> 00:04:43,150 the atmosphere of the earth perhaps only 111 00:04:47,940 --> 00:04:45,190 a few percent of Earth's atmospheric 112 00:04:51,870 --> 00:04:47,950 pressure and this led others even 113 00:04:53,640 --> 00:04:51,880 artists like Chesley bonds Dale to paint 114 00:04:56,790 --> 00:04:53,650 and he was a very famous painter of 115 00:04:58,770 --> 00:04:56,800 planetary images to paint a picture of a 116 00:05:01,920 --> 00:04:58,780 more bleak Mars one that perhaps only 117 00:05:04,050 --> 00:05:01,930 algae could survive at he still had the 118 00:05:06,570 --> 00:05:04,060 straight canals they're going as you see 119 00:05:08,909 --> 00:05:06,580 in this image but it represented a move 120 00:05:10,920 --> 00:05:08,919 towards a more perhaps that's a 121 00:05:13,409 --> 00:05:10,930 realistic view of what Mars was like 122 00:05:15,900 --> 00:05:13,419 although he still clung to the potential 123 00:05:18,090 --> 00:05:15,910 of algal life living at the surface of 124 00:05:20,370 --> 00:05:18,100 Mars and you can see in the foreground a 125 00:05:22,409 --> 00:05:20,380 snowbank and that's actually consistent 126 00:05:24,870 --> 00:05:22,419 with that astronomical observations of 127 00:05:27,390 --> 00:05:24,880 some kind of an ice cap ice caps 128 00:05:30,450 --> 00:05:27,400 actually at the poles of Mars and so in 129 00:05:32,670 --> 00:05:30,460 a way now by 1955 were giving way to a 130 00:05:35,250 --> 00:05:32,680 more realistic view of Mars but one that 131 00:05:37,650 --> 00:05:35,260 still had a ways to go to reach what we 132 00:05:40,950 --> 00:05:37,660 now understand as the surface the 133 00:05:42,870 --> 00:05:40,960 surface environment of Mars the modern 134 00:05:46,080 --> 00:05:42,880 space-age of course I think would really 135 00:05:47,880 --> 00:05:46,090 be defined for Mars as the age in which 136 00:05:50,010 --> 00:05:47,890 we were actually able to send probes 137 00:05:51,960 --> 00:05:50,020 that were close enough to Mars to 138 00:05:53,520 --> 00:05:51,970 provide observations that are superior 139 00:05:56,450 --> 00:05:53,530 to any that we could achieve using 140 00:05:59,850 --> 00:05:56,460 telescopes based on the earth and 141 00:06:03,330 --> 00:05:59,860 certainly the Mariner 4 flyby in 1965 142 00:06:05,850 --> 00:06:03,340 represents a key opening chapter of this 143 00:06:08,219 --> 00:06:05,860 phase of exploration and it was a very 144 00:06:10,290 --> 00:06:08,229 sobering observation indeed of Mars that 145 00:06:13,260 --> 00:06:10,300 only flew by Mars but what you could see 146 00:06:15,480 --> 00:06:13,270 here is a sort of a cratered surface 147 00:06:18,180 --> 00:06:15,490 that quite frankly bears strong 148 00:06:19,710 --> 00:06:18,190 resemblance to the moon and of course we 149 00:06:22,350 --> 00:06:19,720 have much better observations of the 150 00:06:23,820 --> 00:06:22,360 moon because of its proximity and even 151 00:06:25,820 --> 00:06:23,830 before we went there we were pretty sure 152 00:06:28,680 --> 00:06:25,830 this is going to be a very dry bleak and 153 00:06:32,130 --> 00:06:28,690 uninhabitable place and so by the 154 00:06:35,070 --> 00:06:32,140 observations of Mariner in 1965 and 155 00:06:36,779 --> 00:06:35,080 maybe a few years after that we really 156 00:06:38,550 --> 00:06:36,789 were sort of at the nadir of our 157 00:06:40,529 --> 00:06:38,560 perception about the habitability of 158 00:06:41,250 --> 00:06:40,539 Mars we had certainly gone full swing 159 00:06:43,500 --> 00:06:41,260 from the day 160 00:06:45,600 --> 00:06:43,510 use of Percival Lowell and even Chesley 161 00:06:47,340 --> 00:06:45,610 bond still we are now are wondering 162 00:06:49,320 --> 00:06:47,350 whether there was anything more to Mars 163 00:06:51,570 --> 00:06:49,330 than our moon as far as the prospects 164 00:06:53,340 --> 00:06:51,580 for life were concerned so this is sort 165 00:06:57,690 --> 00:06:53,350 of the low point in our perception about 166 00:06:59,420 --> 00:06:57,700 Mars as a potential habitat for life but 167 00:07:02,070 --> 00:06:59,430 as the Viking mission was launched in 168 00:07:04,740 --> 00:07:02,080 1976 and actually some of the previous 169 00:07:08,160 --> 00:07:04,750 an orbiter also was launched even before 170 00:07:10,260 --> 00:07:08,170 Viking our modern perception of Mars 171 00:07:12,420 --> 00:07:10,270 began to take a swing towards the 172 00:07:13,920 --> 00:07:12,430 positive as far as the potential for 173 00:07:16,740 --> 00:07:13,930 habitable environments were concerned 174 00:07:19,830 --> 00:07:16,750 for one thing these spacecraft of the 175 00:07:22,260 --> 00:07:19,840 70s started to make observations of the 176 00:07:25,170 --> 00:07:22,270 surface of Mars that bear resemblance to 177 00:07:26,760 --> 00:07:25,180 some features on the earth for example 178 00:07:30,330 --> 00:07:26,770 if you look to the left of this image a 179 00:07:32,700 --> 00:07:30,340 bit you'll see three features along the 180 00:07:35,790 --> 00:07:32,710 left limb here which are large volcanoes 181 00:07:38,340 --> 00:07:35,800 on Mars very reminiscent of volcanoes on 182 00:07:41,040 --> 00:07:38,350 the earth indicating that a key geologic 183 00:07:43,260 --> 00:07:41,050 process was shared by both planets also 184 00:07:46,530 --> 00:07:43,270 that large gash that you see running 185 00:07:49,440 --> 00:07:46,540 across the front of Mars which we now 186 00:07:51,600 --> 00:07:49,450 know as Valles Marineris represented 187 00:07:54,000 --> 00:07:51,610 some kind of a riff ting or breaking a 188 00:07:56,100 --> 00:07:54,010 part of the Martian crust at some time 189 00:07:58,260 --> 00:07:56,110 in the past rather reminiscent of the 190 00:08:00,810 --> 00:07:58,270 mid-ocean ridge system or other tectonic 191 00:08:02,940 --> 00:08:00,820 features on the earth again speaking to 192 00:08:05,820 --> 00:08:02,950 a similarity between Mars and the earth 193 00:08:08,790 --> 00:08:05,830 and so the closer we looked at Mars the 194 00:08:10,500 --> 00:08:08,800 more we began to see that yes it's quite 195 00:08:12,990 --> 00:08:10,510 different from the earth but perhaps 196 00:08:16,170 --> 00:08:13,000 there are some similarities as well so 197 00:08:18,150 --> 00:08:16,180 this in a way placed mars mars firmly 198 00:08:19,950 --> 00:08:18,160 between the Earth and the moon somewhere 199 00:08:22,080 --> 00:08:19,960 in the middle there between them as sort 200 00:08:24,260 --> 00:08:22,090 of an intermediate example of a planet 201 00:08:28,320 --> 00:08:24,270 and therefore a planetary environment 202 00:08:30,090 --> 00:08:28,330 this little video here shows Mars on the 203 00:08:32,430 --> 00:08:30,100 left and Earth on the right and it shows 204 00:08:34,650 --> 00:08:32,440 that they both have the same tilt the 205 00:08:36,360 --> 00:08:34,660 little highlighting that you see in this 206 00:08:38,280 --> 00:08:36,370 in the lower part of these two Globes 207 00:08:40,469 --> 00:08:38,290 indicates that we have seasons we have 208 00:08:42,450 --> 00:08:40,479 winters and summers both on the earth 209 00:08:45,060 --> 00:08:42,460 and on Mars and so that's another 210 00:08:46,770 --> 00:08:45,070 similarity also we have highlands and 211 00:08:48,600 --> 00:08:46,780 lowlands the lowlands on the earth being 212 00:08:50,310 --> 00:08:48,610 the ocean basins the loans as you can 213 00:08:53,400 --> 00:08:50,320 see on Mars being in the northern 214 00:08:55,140 --> 00:08:53,410 hemisphere and so again this speaks to 215 00:08:58,110 --> 00:08:55,150 some interesting similarities between 216 00:08:59,670 --> 00:08:58,120 Earth and Mars and so that just 217 00:09:01,740 --> 00:08:59,680 heightens our interest now and it 218 00:09:04,230 --> 00:09:01,750 exemplifies what I meant when I said 219 00:09:07,050 --> 00:09:04,240 that our sort of view of Mars is 220 00:09:09,210 --> 00:09:07,060 potentially habitable at some point is 221 00:09:11,550 --> 00:09:09,220 more positive than it was during those 222 00:09:15,030 --> 00:09:11,560 dark years of the 60s with our first fly 223 00:09:16,860 --> 00:09:15,040 by observations and so if we look now at 224 00:09:18,480 --> 00:09:16,870 the earth just to give it drill in a 225 00:09:21,150 --> 00:09:18,490 little bit more closely to the surface 226 00:09:22,800 --> 00:09:21,160 environment the upper panel of course 227 00:09:24,930 --> 00:09:22,810 shows the very familiar Mercator 228 00:09:27,060 --> 00:09:24,940 projection of continents and oceans on 229 00:09:29,400 --> 00:09:27,070 the earth the green highlighting the 230 00:09:32,370 --> 00:09:29,410 very productive forests and grasslands 231 00:09:34,650 --> 00:09:32,380 on the earth and really is a very 232 00:09:36,630 --> 00:09:34,660 familiar landscape to us one that's down 233 00:09:39,300 --> 00:09:36,640 below is showing you the same thing but 234 00:09:40,920 --> 00:09:39,310 with the ocean removed and showing you 235 00:09:43,200 --> 00:09:40,930 and sort of highlighted really in most 236 00:09:45,750 --> 00:09:43,210 cases there in orange this mid-ocean 237 00:09:49,350 --> 00:09:45,760 ridge rift system which is a volcanic 238 00:09:51,720 --> 00:09:49,360 feature it encircles the earth and very 239 00:09:54,090 --> 00:09:51,730 much embodies the geologic activity the 240 00:09:56,030 --> 00:09:54,100 volcanic activity of the earth and quite 241 00:09:58,200 --> 00:09:56,040 frankly that's a very important aspect 242 00:10:01,080 --> 00:09:58,210 contributing to the habitability of our 243 00:10:03,120 --> 00:10:01,090 planet so volcanism is a very important 244 00:10:05,340 --> 00:10:03,130 feature of a planet regarding the 245 00:10:08,220 --> 00:10:05,350 potential for hosting a habitable 246 00:10:09,630 --> 00:10:08,230 environment so in a way then just to 247 00:10:11,550 --> 00:10:09,640 make the transition to what I'll show 248 00:10:13,050 --> 00:10:11,560 next we can think of the continents as 249 00:10:15,990 --> 00:10:13,060 being the highlands of the earth and the 250 00:10:18,150 --> 00:10:16,000 ocean basins as you can see in the in 251 00:10:19,890 --> 00:10:18,160 blue in the upper panel or in the blue 252 00:10:22,980 --> 00:10:19,900 and orange areas in the lower panel 253 00:10:26,490 --> 00:10:22,990 these being sort of the earth lowlands a 254 00:10:29,340 --> 00:10:26,500 key aspect of Earth geography let us now 255 00:10:31,890 --> 00:10:29,350 move to the Mars image again we're 256 00:10:33,930 --> 00:10:31,900 looking at a Mercator projection and as 257 00:10:36,750 --> 00:10:33,940 you can see the blue in the upper part 258 00:10:39,150 --> 00:10:36,760 of this representation represents the 259 00:10:41,480 --> 00:10:39,160 northern lowlands of Mars and as I just 260 00:10:44,130 --> 00:10:41,490 refer back to earth it's analogous to 261 00:10:45,810 --> 00:10:44,140 the ocean basins on the earth although 262 00:10:48,840 --> 00:10:45,820 obviously there's no ocean sitting in 263 00:10:50,400 --> 00:10:48,850 that northern lowlands on Mars then we 264 00:10:52,110 --> 00:10:50,410 have the Southern Highlands which are 265 00:10:54,150 --> 00:10:52,120 shown in the warmer colors in fact if 266 00:10:56,100 --> 00:10:54,160 you look in the lower left here there's 267 00:10:58,800 --> 00:10:56,110 a little little key that indicates 268 00:11:00,540 --> 00:10:58,810 elevation and kilometers where minus 269 00:11:03,540 --> 00:11:00,550 eight is minus eight kilometers below 270 00:11:05,760 --> 00:11:03,550 the mean sort of elevation on Mars and 271 00:11:07,740 --> 00:11:05,770 as you can see Hellas Basin over here 272 00:11:08,940 --> 00:11:07,750 this large impact basin represents the 273 00:11:11,430 --> 00:11:08,950 Louis area 274 00:11:13,650 --> 00:11:11,440 on Mars and then at the top end we have 275 00:11:16,170 --> 00:11:13,660 the big volcanoes I'm these three I 276 00:11:18,840 --> 00:11:16,180 mentioned earlier which really represent 277 00:11:20,760 --> 00:11:18,850 the highs areas highest places on Mars 278 00:11:23,520 --> 00:11:20,770 and as you can see from our dual graph 279 00:11:25,140 --> 00:11:23,530 that's a plus 12 kilometers so that's 280 00:11:27,120 --> 00:11:25,150 the key thing and you can see now that 281 00:11:29,010 --> 00:11:27,130 the similarities between the Earth and 282 00:11:31,440 --> 00:11:29,020 Mars one difference here course be these 283 00:11:33,720 --> 00:11:31,450 very prominent craters every place which 284 00:11:35,960 --> 00:11:33,730 on the earth are much less obvious 285 00:11:38,040 --> 00:11:35,970 because of the constant weathering and 286 00:11:40,590 --> 00:11:38,050 resurfacing of the earth caused by our 287 00:11:43,230 --> 00:11:40,600 climate but the key point I want to make 288 00:11:45,420 --> 00:11:43,240 here with this image is that the density 289 00:11:48,180 --> 00:11:45,430 of craters that you see in the sort of 290 00:11:51,000 --> 00:11:48,190 middle and lower parts of the image here 291 00:11:53,430 --> 00:11:51,010 represent the oldest surfaces on Mars 292 00:11:54,930 --> 00:11:53,440 and to the extent that the early Mars 293 00:11:57,600 --> 00:11:54,940 environment might have been more 294 00:12:00,000 --> 00:11:57,610 interesting for life than later on these 295 00:12:03,120 --> 00:12:00,010 old surfaces represent very important 296 00:12:04,950 --> 00:12:03,130 targets of exploration as we're as you 297 00:12:08,930 --> 00:12:04,960 can see the blue to the north showing 298 00:12:11,400 --> 00:12:08,940 much fewer creators represents a younger 299 00:12:13,200 --> 00:12:11,410 resurfacing of the of that part of the 300 00:12:15,900 --> 00:12:13,210 planet and therefore maybe wouldn't be 301 00:12:17,900 --> 00:12:15,910 the best place to look for evidence of 302 00:12:21,360 --> 00:12:17,910 ancient habitable environments in life 303 00:12:23,070 --> 00:12:21,370 so the other interesting twist to this 304 00:12:24,720 --> 00:12:23,080 though is that now obviously we would 305 00:12:27,360 --> 00:12:24,730 want to explore that heavily cratered 306 00:12:29,940 --> 00:12:27,370 area in the sort of mid latitudes to 307 00:12:32,190 --> 00:12:29,950 southern hemisphere but we have to also 308 00:12:33,870 --> 00:12:32,200 land safely on Mars and to do that we 309 00:12:35,670 --> 00:12:33,880 need as much atmospheric density as 310 00:12:38,370 --> 00:12:35,680 possible as we descend to the surface 311 00:12:39,900 --> 00:12:38,380 and so that means that yeah we should 312 00:12:41,910 --> 00:12:39,910 visit the southern highlands but we 313 00:12:43,920 --> 00:12:41,920 can't visit them too high in fact any 314 00:12:46,860 --> 00:12:43,930 color that you see here that's either 315 00:12:48,690 --> 00:12:46,870 orange red or actually really yellow 316 00:12:50,970 --> 00:12:48,700 orange red or that white at the top 317 00:12:53,460 --> 00:12:50,980 those are elevations that are too high 318 00:12:57,090 --> 00:12:53,470 for us at the moment anyway to risk any 319 00:12:58,560 --> 00:12:57,100 landing mission and so we have to 320 00:13:00,960 --> 00:12:58,570 balance our desire to go to these 321 00:13:03,450 --> 00:13:00,970 ancient terrains against our desire to 322 00:13:06,000 --> 00:13:03,460 land the spacecraft safely so that's a 323 00:13:12,270 --> 00:13:06,010 key tension that we have to cope with in 324 00:13:14,280 --> 00:13:12,280 Mars exploration but as we move closer 325 00:13:16,140 --> 00:13:14,290 and look at some of the features at the 326 00:13:18,420 --> 00:13:16,150 surface of Mars we have really reason to 327 00:13:20,400 --> 00:13:18,430 be excited about that early environment 328 00:13:22,020 --> 00:13:20,410 that I mentioned and that is these large 329 00:13:22,650 --> 00:13:22,030 channels that are flowing across the 330 00:13:24,059 --> 00:13:22,660 surface 331 00:13:26,280 --> 00:13:24,069 they're now quite dry you can see a 332 00:13:28,439 --> 00:13:26,290 little scale bar here on the lower right 333 00:13:30,930 --> 00:13:28,449 corner that little tiny bar there's is 334 00:13:32,699 --> 00:13:30,940 10 kilometers and that indicates that 335 00:13:35,129 --> 00:13:32,709 these are very large channels which 336 00:13:36,420 --> 00:13:35,139 carried large amounts of water from the 337 00:13:38,730 --> 00:13:36,430 Southern Highlands which in this case 338 00:13:40,350 --> 00:13:38,740 would be to the right up down to the 339 00:13:42,540 --> 00:13:40,360 northern lowlands which in this image 340 00:13:44,309 --> 00:13:42,550 would be off to the left and you can see 341 00:13:46,350 --> 00:13:44,319 several examples of these features it's 342 00:13:47,759 --> 00:13:46,360 very prominent one at the top also 343 00:13:49,590 --> 00:13:47,769 another one that seems to erupt from 344 00:13:51,660 --> 00:13:49,600 beneath the surface and then flowing out 345 00:13:53,819 --> 00:13:51,670 towards the northern lowlands and so 346 00:13:57,499 --> 00:13:53,829 this increased our excitement and this 347 00:14:00,420 --> 00:13:57,509 was an observation that was most clearly 348 00:14:03,329 --> 00:14:00,430 documented by the Viking mission again 349 00:14:06,269 --> 00:14:03,339 in the mid 70s and so speaking again to 350 00:14:08,699 --> 00:14:06,279 a different early climate and so the 351 00:14:11,670 --> 00:14:08,709 punch line from this when just going 352 00:14:13,319 --> 00:14:11,680 over what I've summarized so far is that 353 00:14:14,670 --> 00:14:13,329 the Martian environment has really been 354 00:14:17,160 --> 00:14:14,680 more earth-like than that of any other 355 00:14:19,470 --> 00:14:17,170 planet in our solar system again you see 356 00:14:21,090 --> 00:14:19,480 earth on the left and Mars today on the 357 00:14:23,610 --> 00:14:21,100 upper right and then the lower right 358 00:14:25,590 --> 00:14:23,620 maybe an artist's representation of what 359 00:14:29,550 --> 00:14:25,600 Mars might have looked like some 4 + 360 00:14:31,980 --> 00:14:29,560 billion years ago it's clear that it has 361 00:14:34,710 --> 00:14:31,990 some very interesting features that 362 00:14:37,170 --> 00:14:34,720 merit closer inspection and for this 363 00:14:38,910 --> 00:14:37,180 reason Mars has been a major focus in 364 00:14:43,350 --> 00:14:38,920 planetary science exploration in the 365 00:14:46,860 --> 00:14:43,360 last decade or two the next slide then 366 00:14:48,389 --> 00:14:46,870 shows on the left it's shown in 367 00:14:50,340 --> 00:14:48,399 highlighting in blue here some of the 368 00:14:51,870 --> 00:14:50,350 channels and tributaries to the channels 369 00:14:54,689 --> 00:14:51,880 that were documented by the Viking 370 00:14:56,129 --> 00:14:54,699 imagery illustrating again this point 371 00:14:57,780 --> 00:14:56,139 that water used to run across the 372 00:15:00,660 --> 00:14:57,790 surface but these channels don't really 373 00:15:02,819 --> 00:15:00,670 look as robust or as dense as what we 374 00:15:04,379 --> 00:15:02,829 see on the earth and so this led to the 375 00:15:06,240 --> 00:15:04,389 idea that maybe these are just draining 376 00:15:08,730 --> 00:15:06,250 ground water that's coming up in springs 377 00:15:10,889 --> 00:15:08,740 or in any case that the water activity 378 00:15:13,259 --> 00:15:10,899 on Mars was really maybe it was there 379 00:15:15,329 --> 00:15:13,269 episodic ly but not nearly what we see 380 00:15:17,519 --> 00:15:15,339 on the earth but just to show you the 381 00:15:20,790 --> 00:15:17,529 improvement of imagery as on the right 382 00:15:23,519 --> 00:15:20,800 here this is imagery obtained from the 383 00:15:26,460 --> 00:15:23,529 Mars Global Surveyor mission which you 384 00:15:29,670 --> 00:15:26,470 know was launched you know in the past 385 00:15:30,960 --> 00:15:29,680 decade and the colors there are the same 386 00:15:34,170 --> 00:15:30,970 kinds of colors I showed you earlier 387 00:15:35,940 --> 00:15:34,180 with Mars map illustrating much better 388 00:15:37,980 --> 00:15:35,950 elevation control in our 389 00:15:39,510 --> 00:15:37,990 mapping of the surface and the little 390 00:15:41,940 --> 00:15:39,520 yellow lines that you see running all 391 00:15:43,770 --> 00:15:41,950 over here represent the channels now 392 00:15:45,840 --> 00:15:43,780 that we can document using this higher 393 00:15:47,790 --> 00:15:45,850 quality image well the interesting point 394 00:15:49,380 --> 00:15:47,800 is that the image on the right is taken 395 00:15:51,630 --> 00:15:49,390 of the same place that you're seeing on 396 00:15:54,420 --> 00:15:51,640 the left and it just shows how superior 397 00:15:57,480 --> 00:15:54,430 resolution of the imagery is making for 398 00:16:00,090 --> 00:15:57,490 a much more exciting observation about 399 00:16:01,950 --> 00:16:00,100 Mars that gee these are now channel 400 00:16:03,740 --> 00:16:01,960 densities that are approaching drainage 401 00:16:06,120 --> 00:16:03,750 channel densities on the earth and the 402 00:16:07,560 --> 00:16:06,130 argument for precipitation having 403 00:16:10,380 --> 00:16:07,570 occurred at some time in the distant 404 00:16:12,630 --> 00:16:10,390 past on Mars seems to be very compelling 405 00:16:14,850 --> 00:16:12,640 now so the key point is that our 406 00:16:16,650 --> 00:16:14,860 discoveries are very much tied to the 407 00:16:18,660 --> 00:16:16,660 quality of the observations that we can 408 00:16:20,550 --> 00:16:18,670 make and that the superior orbital 409 00:16:22,380 --> 00:16:20,560 imagery that we've been enjoying now 410 00:16:25,680 --> 00:16:22,390 since the Mars Global Surveyor mission 411 00:16:28,800 --> 00:16:25,690 of 1996 I are going to have been a clear 412 00:16:30,630 --> 00:16:28,810 driver in our exploration of Mars and in 413 00:16:32,640 --> 00:16:30,640 fact this image which again is a 414 00:16:34,530 --> 00:16:32,650 Mercator projection showing the northern 415 00:16:36,060 --> 00:16:34,540 lowlands to the high upper part of the 416 00:16:39,120 --> 00:16:36,070 image in the Southern Highlands to the 417 00:16:41,070 --> 00:16:39,130 lower part of the image highlights an 418 00:16:43,800 --> 00:16:41,080 inventory of features that are quite 419 00:16:45,600 --> 00:16:43,810 relevant to our evaluation of water if 420 00:16:48,540 --> 00:16:45,610 you look in the upper left sub panel 421 00:16:50,670 --> 00:16:48,550 here you see a nice dense drainage 422 00:16:52,500 --> 00:16:50,680 network that sort of channels watered 423 00:16:55,320 --> 00:16:52,510 down towards this lower right part of 424 00:16:57,060 --> 00:16:55,330 the image that is an example of what we 425 00:16:58,470 --> 00:16:57,070 are showing here as these little blue 426 00:17:01,590 --> 00:16:58,480 squiggles that you see all the way 427 00:17:04,650 --> 00:17:01,600 across this Mercator map up here in the 428 00:17:06,510 --> 00:17:04,660 upper right we see a a crater that has 429 00:17:08,670 --> 00:17:06,520 had a channel flowing into it and a 430 00:17:11,130 --> 00:17:08,680 channel flowing out but in any case it's 431 00:17:12,930 --> 00:17:11,140 a crater that seems to have had water in 432 00:17:15,150 --> 00:17:12,940 it at some point in the past basically a 433 00:17:16,829 --> 00:17:15,160 crater lake all these little red dots 434 00:17:19,170 --> 00:17:16,839 are that you see here with the white 435 00:17:20,490 --> 00:17:19,180 centers are examples of these types of 436 00:17:23,069 --> 00:17:20,500 crater lakes that we have been 437 00:17:24,900 --> 00:17:23,079 documenting on Mars and as you see just 438 00:17:26,550 --> 00:17:24,910 south of this what we call the dichotomy 439 00:17:28,860 --> 00:17:26,560 boundary between the northern lowlands 440 00:17:30,660 --> 00:17:28,870 and the southern highlands a very high 441 00:17:33,360 --> 00:17:30,670 density of these features both the 442 00:17:34,980 --> 00:17:33,370 channels as well as the lakes indicating 443 00:17:36,750 --> 00:17:34,990 that there was a fair amount of 444 00:17:39,000 --> 00:17:36,760 precipitation at some time in the past 445 00:17:40,770 --> 00:17:39,010 on Mars to conform these features the 446 00:17:43,050 --> 00:17:40,780 only place where they seem sparse is in 447 00:17:45,990 --> 00:17:43,060 this area here but that just happens to 448 00:17:47,670 --> 00:17:46,000 be the place where volcanism has covered 449 00:17:49,620 --> 00:17:47,680 the surface with lava flows and 450 00:17:52,050 --> 00:17:49,630 basically obscured these 451 00:17:54,510 --> 00:17:52,060 features where they happen to be too 452 00:17:57,330 --> 00:17:54,520 close to the volcanoes so it's probably 453 00:17:59,580 --> 00:17:57,340 a reasonable extrapolation to say that 454 00:18:02,070 --> 00:17:59,590 we had very dense features evidencing 455 00:18:04,440 --> 00:18:02,080 precipitation on Mars right just south 456 00:18:07,200 --> 00:18:04,450 of the dichotomy boundary and this after 457 00:18:09,000 --> 00:18:07,210 three more more billion years of Mars 458 00:18:11,250 --> 00:18:09,010 history that could have obscured a lot 459 00:18:13,560 --> 00:18:11,260 of the features that were once there so 460 00:18:16,050 --> 00:18:13,570 the argument for precipitation and water 461 00:18:18,450 --> 00:18:16,060 on Mars just from the landscape analysis 462 00:18:21,330 --> 00:18:18,460 alone has become quite more compelling 463 00:18:23,070 --> 00:18:21,340 in recent years so with this a couple of 464 00:18:25,230 --> 00:18:23,080 thought questions to test your 465 00:18:27,600 --> 00:18:25,240 comprehension one would be in what ways 466 00:18:29,220 --> 00:18:27,610 is more similar to earth and name at 467 00:18:30,900 --> 00:18:29,230 least three characteristics that you can 468 00:18:33,030 --> 00:18:30,910 think of that are similar between Mars 469 00:18:34,920 --> 00:18:33,040 and Earth so that's one question and 470 00:18:37,050 --> 00:18:34,930 another one of course could be how r 471 00:18:39,780 --> 00:18:37,060 Mars and the earth different provide at 472 00:18:42,300 --> 00:18:39,790 least three examples of that and so I 473 00:18:44,700 --> 00:18:42,310 won't provide the answers now but it is 474 00:18:47,100 --> 00:18:44,710 a bit of test of your comprehension of 475 00:18:49,080 --> 00:18:47,110 what what I've just explained okay with 476 00:18:51,450 --> 00:18:49,090 that let's move on again as it just as I 477 00:18:53,640 --> 00:18:51,460 said better resolution images from orbit 478 00:18:55,050 --> 00:18:53,650 tell us a lot more about what Mars 479 00:18:57,240 --> 00:18:55,060 environments might have been like in the 480 00:18:59,370 --> 00:18:57,250 past it's hard to argue that getting 481 00:19:01,080 --> 00:18:59,380 down on the ground and looking up close 482 00:19:04,740 --> 00:19:01,090 and personal to rocks and other features 483 00:19:07,160 --> 00:19:04,750 is you know even more compelling way to 484 00:19:09,600 --> 00:19:07,170 really understand the story about Mars 485 00:19:12,390 --> 00:19:09,610 these are some tools here that a 486 00:19:14,850 --> 00:19:12,400 geologist uses as he or she goes out 487 00:19:16,500 --> 00:19:14,860 into the field to analyze rocks and to 488 00:19:19,440 --> 00:19:16,510 try to understand the story that the 489 00:19:21,390 --> 00:19:19,450 rocks are telling him or her the boots 490 00:19:22,800 --> 00:19:21,400 represent moving around looking at 491 00:19:25,260 --> 00:19:22,810 different rocks looking at different 492 00:19:27,540 --> 00:19:25,270 outcrops and features so mobility is a 493 00:19:30,680 --> 00:19:27,550 very important character of a field 494 00:19:33,290 --> 00:19:30,690 geologist over on the Left we see 495 00:19:35,090 --> 00:19:33,300 binoculars glasses and a hand lens 496 00:19:37,500 --> 00:19:35,100 representing the importance of 497 00:19:39,720 --> 00:19:37,510 observation visual observations first 498 00:19:41,970 --> 00:19:39,730 from a distance than up close and then 499 00:19:43,440 --> 00:19:41,980 really up close with a hand lens to 500 00:19:45,810 --> 00:19:43,450 observe something like the you see you 501 00:19:48,330 --> 00:19:45,820 there the rock sort of it a little lower 502 00:19:49,920 --> 00:19:48,340 left center there the compass here 503 00:19:51,720 --> 00:19:49,930 represents the importance of the 504 00:19:54,210 --> 00:19:51,730 geologist knowing Viet where he or she 505 00:19:56,190 --> 00:19:54,220 is in the field at any one time so that 506 00:19:58,710 --> 00:19:56,200 they can record their observations to 507 00:20:00,540 --> 00:19:58,720 build a map the rock hammer represents 508 00:20:02,700 --> 00:20:00,550 the importance sometimes of breaking off 509 00:20:03,510 --> 00:20:02,710 the surface of a rock to get to a nice 510 00:20:05,610 --> 00:20:03,520 fresh and tear 511 00:20:07,410 --> 00:20:05,620 here this little rock sample to the left 512 00:20:09,000 --> 00:20:07,420 of the hammer of course is something 513 00:20:11,010 --> 00:20:09,010 that's been sawed open so that you can 514 00:20:13,860 --> 00:20:11,020 see very nicely the fabric that's inside 515 00:20:15,270 --> 00:20:13,870 so the ability to look at fresh rock 516 00:20:17,070 --> 00:20:15,280 surface and then it's a little tiny 517 00:20:19,590 --> 00:20:17,080 bottle to the left of the boot indicates 518 00:20:21,720 --> 00:20:19,600 maybe even do some rudimentary analyses 519 00:20:23,580 --> 00:20:21,730 this is just acid to see if the rock 520 00:20:25,650 --> 00:20:23,590 dissolves as a limestone would dissolve 521 00:20:27,210 --> 00:20:25,660 to get more of a sense of the 522 00:20:29,730 --> 00:20:27,220 composition of the rock in the field 523 00:20:32,490 --> 00:20:29,740 these are all very important aspects of 524 00:20:35,460 --> 00:20:32,500 field geology and one that we have tried 525 00:20:37,200 --> 00:20:35,470 to now replicate in Rovers that have 526 00:20:39,990 --> 00:20:37,210 been built to go to the surface of Mars 527 00:20:42,000 --> 00:20:40,000 in 1996 that's a little bread box size 528 00:20:45,210 --> 00:20:42,010 Sojourner represented our first attempt 529 00:20:47,750 --> 00:20:45,220 to do this and it really it made some 530 00:20:50,550 --> 00:20:47,760 interesting observations about Mars 531 00:20:52,650 --> 00:20:50,560 ellen aspects about the composition of 532 00:20:55,020 --> 00:20:52,660 the rocks indicating the how the crust 533 00:20:57,300 --> 00:20:55,030 of Mars may have evolved with volcanic 534 00:20:59,300 --> 00:20:57,310 activity in the early days Sojourner 535 00:21:01,680 --> 00:20:59,310 didn't really make a number of 536 00:21:03,450 --> 00:21:01,690 compelling observations about the story 537 00:21:05,670 --> 00:21:03,460 of water even though we landed it in one 538 00:21:08,580 --> 00:21:05,680 of those ancient large channels but it 539 00:21:09,780 --> 00:21:08,590 was really a significant mission as it 540 00:21:12,330 --> 00:21:09,790 was designed to be and that is a 541 00:21:14,580 --> 00:21:12,340 pathfinder to really do a path finding 542 00:21:16,260 --> 00:21:14,590 mission to understand how to operate a 543 00:21:18,150 --> 00:21:16,270 rover on the surface of Mars and the 544 00:21:19,560 --> 00:21:18,160 types of instruments that would be 545 00:21:21,600 --> 00:21:19,570 important to really make the key 546 00:21:23,760 --> 00:21:21,610 observations to address this question of 547 00:21:26,850 --> 00:21:23,770 just how active and for how long did 548 00:21:28,590 --> 00:21:26,860 water exist on the surface of Mars the 549 00:21:30,750 --> 00:21:28,600 the benefits of our knowledge from 550 00:21:32,940 --> 00:21:30,760 Sojourner led directly to the design 551 00:21:34,290 --> 00:21:32,950 successful design i would add of spirit 552 00:21:36,840 --> 00:21:34,300 and opportunity that were launched in 553 00:21:39,480 --> 00:21:36,850 2003 and i'd like to go over a little 554 00:21:40,800 --> 00:21:39,490 bit of summary of their findings just to 555 00:21:43,110 --> 00:21:40,810 illustrate the importance of that 556 00:21:45,000 --> 00:21:43,120 mission and how it feeds to our quest 557 00:21:47,310 --> 00:21:45,010 year to understand the potential for 558 00:21:49,530 --> 00:21:47,320 habitable environments on Mars and then 559 00:21:53,040 --> 00:21:49,540 finally the recent launch of curiosity 560 00:21:55,200 --> 00:21:53,050 and landing in August of 2012 represents 561 00:21:57,450 --> 00:21:55,210 a further extension of our capabilities 562 00:21:59,370 --> 00:21:57,460 as well as our scientific knowledge of 563 00:22:01,590 --> 00:21:59,380 Mars and certainly what will hopefully 564 00:22:04,230 --> 00:22:01,600 lead to an increased scientific 565 00:22:06,570 --> 00:22:04,240 knowledge of the surface of Mars so I'd 566 00:22:09,300 --> 00:22:06,580 like Ben just to go back to our Mars map 567 00:22:13,230 --> 00:22:09,310 and now indicate the places where nASA 568 00:22:15,630 --> 00:22:13,240 has sent some spacecraft to the surface 569 00:22:16,830 --> 00:22:15,640 of Mars and NASA landing sites as of 570 00:22:19,590 --> 00:22:16,840 2011 571 00:22:23,430 --> 00:22:19,600 and to now circle both opportunity and 572 00:22:25,049 --> 00:22:23,440 spirit here as the two landing sites 573 00:22:27,029 --> 00:22:25,059 that we pick and again as you can see 574 00:22:28,680 --> 00:22:27,039 what I said earlier we white really 575 00:22:31,320 --> 00:22:28,690 wanted to get to the north to the 576 00:22:33,570 --> 00:22:31,330 southern highlands of Mars but we also 577 00:22:35,310 --> 00:22:33,580 had to land into place safely and so we 578 00:22:37,610 --> 00:22:35,320 are in these sort of green zone here 579 00:22:42,269 --> 00:22:37,620 which represents sort of an intermediate 580 00:22:44,190 --> 00:22:42,279 elevation on Mars so first I will take 581 00:22:46,080 --> 00:22:44,200 us to the opportunity site just to get 582 00:22:48,360 --> 00:22:46,090 some of the key observations that were 583 00:22:50,610 --> 00:22:48,370 made by that and this was a place that 584 00:22:52,649 --> 00:22:50,620 we picked based on evidence of a certain 585 00:22:54,269 --> 00:22:52,659 mineral called hematite grey hematite 586 00:22:56,399 --> 00:22:54,279 which indicated that liquid water might 587 00:22:59,100 --> 00:22:56,409 have been active at the surface and when 588 00:23:01,049 --> 00:22:59,110 we landed there you're looking out from 589 00:23:02,760 --> 00:23:01,059 where we landed at an outcrop that's 590 00:23:05,039 --> 00:23:02,770 only about half a meter high here as 591 00:23:06,720 --> 00:23:05,049 shown by this bar but we've made an 592 00:23:08,760 --> 00:23:06,730 observation of a number of features that 593 00:23:11,130 --> 00:23:08,770 were consistent with water having been 594 00:23:13,680 --> 00:23:11,140 present first of all this yellowish 595 00:23:15,630 --> 00:23:13,690 color that you see here are rocks along 596 00:23:17,639 --> 00:23:15,640 the rim of the crater where we landed 597 00:23:19,950 --> 00:23:17,649 that show what we call sulfate minerals 598 00:23:22,080 --> 00:23:19,960 these are minerals that are soluble in 599 00:23:23,639 --> 00:23:22,090 water and very much different from a 600 00:23:26,370 --> 00:23:23,649 volcanic rock and they indicate that 601 00:23:28,380 --> 00:23:26,380 somehow water had to be involved in the 602 00:23:31,919 --> 00:23:28,390 in the formation of these rocks and so 603 00:23:33,860 --> 00:23:31,929 that was very exciting we found again 604 00:23:36,690 --> 00:23:33,870 these iron oxide or hematite rich 605 00:23:37,649 --> 00:23:36,700 concretions little spherical objects 606 00:23:39,510 --> 00:23:37,659 that you can see them littering the 607 00:23:42,240 --> 00:23:39,520 surface we found there in the rocks and 608 00:23:44,460 --> 00:23:42,250 these are consistent with formation in a 609 00:23:46,649 --> 00:23:44,470 saturated water environment where the 610 00:23:48,620 --> 00:23:46,659 iron oxide precipitated actually 611 00:23:51,360 --> 00:23:48,630 probably as an iron hydroxide initially 612 00:23:52,830 --> 00:23:51,370 precipitated out of a solution and 613 00:23:54,779 --> 00:23:52,840 pretty much had to be an acidic solution 614 00:23:57,840 --> 00:23:54,789 to form these little concretion these 615 00:23:59,760 --> 00:23:57,850 little sphere riyals we found another a 616 00:24:01,769 --> 00:23:59,770 bunch of other features again that were 617 00:24:03,510 --> 00:24:01,779 consistent with the presence of water 618 00:24:05,940 --> 00:24:03,520 which I can elaborate a little bit more 619 00:24:08,970 --> 00:24:05,950 on the next slide here now we're zooming 620 00:24:11,600 --> 00:24:08,980 in a close up of view of Iraq this using 621 00:24:13,919 --> 00:24:11,610 that little microscopic imager tool 622 00:24:16,019 --> 00:24:13,929 analogous to what a geologists would 623 00:24:17,880 --> 00:24:16,029 have and here you see these little 624 00:24:21,360 --> 00:24:17,890 spheria lytic hematite concretions 625 00:24:23,610 --> 00:24:21,370 embedded in the rock we see basically 626 00:24:25,409 --> 00:24:23,620 little cavities in the rock that used to 627 00:24:27,450 --> 00:24:25,419 contain some kind of a plating mineral 628 00:24:28,560 --> 00:24:27,460 but has since been dissolved away well 629 00:24:30,419 --> 00:24:28,570 the just the fact that it's been 630 00:24:34,049 --> 00:24:30,429 dissolved away means that it was water 631 00:24:36,359 --> 00:24:34,059 which means water had to be involved and 632 00:24:38,310 --> 00:24:36,369 but and of course but for us and many of 633 00:24:40,379 --> 00:24:38,320 us one of the most exciting observations 634 00:24:42,389 --> 00:24:40,389 was the observation of these ripple 635 00:24:46,379 --> 00:24:42,399 crests as you can see up here in the 636 00:24:48,060 --> 00:24:46,389 upper right and these are the same kinds 637 00:24:50,100 --> 00:24:48,070 of ripples as you would see on a beach 638 00:24:53,220 --> 00:24:50,110 or in a lake or any place where waters 639 00:24:55,440 --> 00:24:53,230 flowing across the surface so not only 640 00:24:57,659 --> 00:24:55,450 indicates that liquid water is present 641 00:25:00,060 --> 00:24:57,669 but it indicated that the liquid water 642 00:25:02,039 --> 00:25:00,070 was present at the surface and this in 643 00:25:04,379 --> 00:25:02,049 head carries a clear implication for the 644 00:25:06,570 --> 00:25:04,389 climate of Mars at that time the climate 645 00:25:08,879 --> 00:25:06,580 had to permit liquid water to be stable 646 00:25:12,450 --> 00:25:08,889 at the surface of Mars and that is not 647 00:25:14,519 --> 00:25:12,460 the case today Mars is so dry and cold 648 00:25:16,830 --> 00:25:14,529 today that liquid water is not stable 649 00:25:19,560 --> 00:25:16,840 and so this was a very important 650 00:25:21,859 --> 00:25:19,570 observation made by opportunity so as 651 00:25:24,960 --> 00:25:21,869 significant as these observations were 652 00:25:27,299 --> 00:25:24,970 just they really represent you know 653 00:25:29,669 --> 00:25:27,309 observations of just a half a meter of a 654 00:25:32,669 --> 00:25:29,679 rock layer we really would like to know 655 00:25:34,889 --> 00:25:32,679 more about what was the history of Mars 656 00:25:37,080 --> 00:25:34,899 environment at that time over here you 657 00:25:40,350 --> 00:25:37,090 see this Eagle crater this little tiny 658 00:25:42,060 --> 00:25:40,360 crater where opportunity landed and so 659 00:25:43,440 --> 00:25:42,070 we got into this mode of going to bigger 660 00:25:45,539 --> 00:25:43,450 and bigger craters here you see 661 00:25:47,700 --> 00:25:45,549 endurance crater and then this very long 662 00:25:50,639 --> 00:25:47,710 drive over here to Victoria crater and 663 00:25:52,259 --> 00:25:50,649 now we have driven off and now arrived 664 00:25:54,029 --> 00:25:52,269 at endeavour crater which is an even 665 00:25:56,310 --> 00:25:54,039 larger creator still why are we going to 666 00:25:59,279 --> 00:25:56,320 creators because craters dig down into 667 00:26:01,169 --> 00:25:59,289 the surface subsurface they expose more 668 00:26:03,119 --> 00:26:01,179 rock layers so you can think of 669 00:26:05,399 --> 00:26:03,129 successive layers of rock as being 670 00:26:07,609 --> 00:26:05,409 successive pages in this in a story book 671 00:26:10,440 --> 00:26:07,619 about the early history of Mars 672 00:26:12,180 --> 00:26:10,450 environment and so if one page is very 673 00:26:13,980 --> 00:26:12,190 interesting than the things you want to 674 00:26:15,749 --> 00:26:13,990 do with any good book or what record is 675 00:26:17,999 --> 00:26:15,759 to look at more pages to learn more 676 00:26:20,279 --> 00:26:18,009 about the progression of the story and 677 00:26:22,409 --> 00:26:20,289 so by going to endurance crater we go 678 00:26:24,480 --> 00:26:22,419 two more pages of the book and when we 679 00:26:27,029 --> 00:26:24,490 got there here's the view of the crater 680 00:26:30,029 --> 00:26:27,039 170 meters across much bigger actually 681 00:26:32,070 --> 00:26:30,039 160 meters much bigger than Eagle crater 682 00:26:34,739 --> 00:26:32,080 and much deeper and because of the depth 683 00:26:36,899 --> 00:26:34,749 we're able to access this layer of rocks 684 00:26:38,340 --> 00:26:36,909 that you see here that tell us more 685 00:26:41,029 --> 00:26:38,350 about the story of this early 686 00:26:43,529 --> 00:26:41,039 environment and to just be quite brief 687 00:26:44,250 --> 00:26:43,539 basically it's a story of Playa lakes 688 00:26:45,780 --> 00:26:44,260 mall 689 00:26:47,520 --> 00:26:45,790 ending bodies of water much like the 690 00:26:50,100 --> 00:26:47,530 ones we saw evidence for back at our 691 00:26:52,170 --> 00:26:50,110 landing site but also under lane by 692 00:26:53,880 --> 00:26:52,180 layers of what we call sand sheets which 693 00:26:56,820 --> 00:26:53,890 represent again water but not in 694 00:26:58,560 --> 00:26:56,830 standing mode just moist sand and then 695 00:27:01,230 --> 00:26:58,570 much thicker layers of what we 696 00:27:03,990 --> 00:27:01,240 characterize as sand dunes and so we 697 00:27:06,390 --> 00:27:04,000 think of a an ancient landscape of sand 698 00:27:08,670 --> 00:27:06,400 dunes wet sand sheets and playa Lakes 699 00:27:10,500 --> 00:27:08,680 much like for example what you would see 700 00:27:12,960 --> 00:27:10,510 at white sands national monument in New 701 00:27:15,810 --> 00:27:12,970 Mexico so now we get an idea about not 702 00:27:17,520 --> 00:27:15,820 only more of through time of what the 703 00:27:18,900 --> 00:27:17,530 environment was like but also more of 704 00:27:21,000 --> 00:27:18,910 what the landscape would have been like 705 00:27:23,160 --> 00:27:21,010 at that time and the important thing is 706 00:27:25,710 --> 00:27:23,170 that included standing bodies of water 707 00:27:29,220 --> 00:27:25,720 at the surface so this mission of 708 00:27:31,530 --> 00:27:29,230 opportunity really demonstrated that 709 00:27:33,360 --> 00:27:31,540 that surface environment was early 710 00:27:35,310 --> 00:27:33,370 environment was really different water 711 00:27:37,140 --> 00:27:35,320 played a more prominent role that's a 712 00:27:39,660 --> 00:27:37,150 big step towards the potential for 713 00:27:41,910 --> 00:27:39,670 habitable environments on early Mars so 714 00:27:43,740 --> 00:27:41,920 let me now expand this concept of 715 00:27:46,140 --> 00:27:43,750 habitable environments beyond just water 716 00:27:47,970 --> 00:27:46,150 this little green cube you see here 717 00:27:49,560 --> 00:27:47,980 represents what I would say the locus of 718 00:27:51,810 --> 00:27:49,570 environments within which life could 719 00:27:54,090 --> 00:27:51,820 survive and for that to be the case 720 00:27:56,490 --> 00:27:54,100 there have to be at least three basic 721 00:27:57,810 --> 00:27:56,500 features satisfied one is you have to 722 00:28:01,050 --> 00:27:57,820 have water available and that's that 723 00:28:02,430 --> 00:28:01,060 horizontal axis here if it's too if the 724 00:28:04,740 --> 00:28:02,440 things that are in the water are too 725 00:28:06,210 --> 00:28:04,750 dilute you just can't get life going but 726 00:28:07,920 --> 00:28:06,220 also if there's just not enough water 727 00:28:10,650 --> 00:28:07,930 available it to keep you chemically 728 00:28:12,810 --> 00:28:10,660 available life cannot take a foothold 729 00:28:14,370 --> 00:28:12,820 but at the same token the same 730 00:28:16,860 --> 00:28:14,380 environment has to have an available 731 00:28:19,260 --> 00:28:16,870 energy source all of us need energy to 732 00:28:21,570 --> 00:28:19,270 survive that's why we have you know our 733 00:28:24,600 --> 00:28:21,580 meals during the day that's why plants 734 00:28:26,310 --> 00:28:24,610 have to absorb the sunlight to make 735 00:28:28,200 --> 00:28:26,320 energy for themselves this is a key 736 00:28:30,750 --> 00:28:28,210 requirement for life and of course the 737 00:28:33,210 --> 00:28:30,760 third one is that we have to have the 738 00:28:35,010 --> 00:28:33,220 ingredients the carbon the sulfur the 739 00:28:38,430 --> 00:28:35,020 nitrogen and other elements available 740 00:28:39,990 --> 00:28:38,440 for life to build ourselves so all of 741 00:28:41,940 --> 00:28:40,000 these things have to be present at the 742 00:28:43,800 --> 00:28:41,950 same place at the same time can we 743 00:28:46,260 --> 00:28:43,810 demonstrate that that was ever the case 744 00:28:49,560 --> 00:28:46,270 at any place on Mars at any time in the 745 00:28:53,970 --> 00:28:49,570 past with that I'd like them to move to 746 00:28:55,530 --> 00:28:53,980 our other landing site at the Gusev 747 00:28:57,690 --> 00:28:55,540 crater which is really on the other side 748 00:28:58,140 --> 00:28:57,700 of the planet from where opportunity 749 00:29:01,800 --> 00:28:58,150 landed 750 00:29:03,540 --> 00:29:01,810 meridiani to a crater that clearly had 751 00:29:05,340 --> 00:29:03,550 water in it at some point you see here 752 00:29:06,540 --> 00:29:05,350 my team Valles flowing into the crater 753 00:29:09,510 --> 00:29:06,550 and then eventually the Creator 754 00:29:11,070 --> 00:29:09,520 overtopped and water flowed into the 755 00:29:13,290 --> 00:29:11,080 northern lowlands and for good measure 756 00:29:16,350 --> 00:29:13,300 here we even have a volcano nearby in 757 00:29:18,390 --> 00:29:16,360 the form Apollinaris Patera so just from 758 00:29:20,370 --> 00:29:18,400 the landscape of this view you can see 759 00:29:22,800 --> 00:29:20,380 that water must have been there in the 760 00:29:24,630 --> 00:29:22,810 past and so unlike the mineral that we 761 00:29:26,880 --> 00:29:24,640 found at the opportunity site at 762 00:29:29,220 --> 00:29:26,890 meridiani it was the landscape that 763 00:29:30,780 --> 00:29:29,230 compelled us to land here at Gusev 764 00:29:33,120 --> 00:29:30,790 crater which you can see is a pretty 765 00:29:35,340 --> 00:29:33,130 good-sized crater 180 meters kilometers 766 00:29:37,500 --> 00:29:35,350 across so let's go to the next slide 767 00:29:40,500 --> 00:29:37,510 however though when we landed way up 768 00:29:43,980 --> 00:29:40,510 here in the upper left corner we landed 769 00:29:46,200 --> 00:29:43,990 on a vast plains of lava rock so even 770 00:29:48,270 --> 00:29:46,210 though this huge crater had water in at 771 00:29:51,510 --> 00:29:48,280 one point guess what subsequent to that 772 00:29:53,670 --> 00:29:51,520 time lava flows had really covered much 773 00:29:55,920 --> 00:29:53,680 of this floor of this crater well this 774 00:29:57,570 --> 00:29:55,930 is a not great news for our little Rover 775 00:29:59,760 --> 00:29:57,580 because our little Rover makes a living 776 00:30:02,100 --> 00:29:59,770 actually analyzing rocks up close and 777 00:30:03,690 --> 00:30:02,110 personal for evidence of water and if we 778 00:30:05,460 --> 00:30:03,700 had a big lava flow that covered all 779 00:30:07,410 --> 00:30:05,470 that evidence then we've got a problem 780 00:30:09,600 --> 00:30:07,420 here as they would say houston we have a 781 00:30:11,700 --> 00:30:09,610 problem here well the good news is that 782 00:30:13,200 --> 00:30:11,710 as we look out from our landing site you 783 00:30:14,760 --> 00:30:13,210 can see in the upper right image here 784 00:30:17,520 --> 00:30:14,770 there were some mountains or hills off 785 00:30:19,050 --> 00:30:17,530 to the southeast which looks different 786 00:30:20,880 --> 00:30:19,060 from these lava Plains and these are 787 00:30:23,910 --> 00:30:20,890 these Columbia Hills that you see now in 788 00:30:26,340 --> 00:30:23,920 the lower big image you see also the 789 00:30:28,350 --> 00:30:26,350 orange represents our decision to drive 790 00:30:30,330 --> 00:30:28,360 over there this is our trail that we are 791 00:30:33,120 --> 00:30:30,340 path that we took and if you look very 792 00:30:35,280 --> 00:30:33,130 closely between the margin between the 793 00:30:37,020 --> 00:30:35,290 hills and the plains to the to the west 794 00:30:38,880 --> 00:30:37,030 you see what looks like almost like a 795 00:30:41,100 --> 00:30:38,890 shoreline feature and this actually is 796 00:30:43,200 --> 00:30:41,110 the edge of the lava flow indicating 797 00:30:44,310 --> 00:30:43,210 that these hills are something different 798 00:30:46,500 --> 00:30:44,320 in fact there's something of the 799 00:30:48,930 --> 00:30:46,510 underlay the lava flow and therefore 800 00:30:50,520 --> 00:30:48,940 they're probably older and so this is 801 00:30:52,530 --> 00:30:50,530 the place to go to see if we could 802 00:30:55,290 --> 00:30:52,540 finally see evidence for water having 803 00:30:58,380 --> 00:30:55,300 played a role in Gusev crater on Mars 804 00:31:00,090 --> 00:30:58,390 and of course we did drive over there as 805 00:31:03,120 --> 00:31:00,100 this map shows and we did indeed find 806 00:31:06,090 --> 00:31:03,130 some additional evidence for water and 807 00:31:09,060 --> 00:31:06,100 just to be quite quick about this of the 808 00:31:11,130 --> 00:31:09,070 indicators of liquid water could be sort 809 00:31:11,670 --> 00:31:11,140 of a raid on a scale here of very low 810 00:31:15,570 --> 00:31:11,680 water 811 00:31:17,280 --> 00:31:15,580 availability clearly at the low end if 812 00:31:19,530 --> 00:31:17,290 you're looking at fresh volcanic rocks 813 00:31:21,600 --> 00:31:19,540 that are still pretty much unaltered by 814 00:31:23,760 --> 00:31:21,610 water if you're looking at soil horizons 815 00:31:25,950 --> 00:31:23,770 we're both insoluble minerals are 816 00:31:28,020 --> 00:31:25,960 uniformly mixed with soluble salts as 817 00:31:30,300 --> 00:31:28,030 you would expect in a very dry 818 00:31:32,250 --> 00:31:30,310 environment where maybe only the wind is 819 00:31:34,320 --> 00:31:32,260 what's blowing things around then that's 820 00:31:36,710 --> 00:31:34,330 not much evidence for water but at the 821 00:31:39,000 --> 00:31:36,720 other end if you're looking at place at 822 00:31:41,760 --> 00:31:39,010 deposits where the rocks have been 823 00:31:44,850 --> 00:31:41,770 altered to clays or salts or other 824 00:31:46,950 --> 00:31:44,860 things and where they've even been 825 00:31:48,870 --> 00:31:46,960 transported around by water this 826 00:31:50,880 --> 00:31:48,880 obviously represents a very extensive 827 00:31:53,940 --> 00:31:50,890 evidence for water having been present 828 00:31:55,680 --> 00:31:53,950 and indeed as we went to the Columbia 829 00:31:57,800 --> 00:31:55,690 Hills husband Hill and some of the other 830 00:32:00,600 --> 00:31:57,810 features I'll mention we did actually 831 00:32:02,790 --> 00:32:00,610 find evidence that water had been quite 832 00:32:05,640 --> 00:32:02,800 extensively present so in that sense 833 00:32:07,530 --> 00:32:05,650 then a spirit had sort of pulled even 834 00:32:09,800 --> 00:32:07,540 with opportunity of being able to prove 835 00:32:13,320 --> 00:32:09,810 that liquid water had been present in 836 00:32:14,880 --> 00:32:13,330 air at some time in the past but it 837 00:32:17,490 --> 00:32:14,890 really got quite exciting for us we 838 00:32:19,020 --> 00:32:17,500 drove over to husband Hill we drove up 839 00:32:21,360 --> 00:32:19,030 and this is where we found that initial 840 00:32:23,130 --> 00:32:21,370 evidence for water but then we drove 841 00:32:24,900 --> 00:32:23,140 down into a place called inter-basin to 842 00:32:27,090 --> 00:32:24,910 a very fascinating feature called home 843 00:32:28,680 --> 00:32:27,100 plate and that really was the site at 844 00:32:30,780 --> 00:32:28,690 which a number of additional exciting 845 00:32:33,180 --> 00:32:30,790 observations were made relevant to this 846 00:32:35,520 --> 00:32:33,190 theme of out habitable environments we 847 00:32:38,100 --> 00:32:35,530 found at home plate that it was a 848 00:32:40,170 --> 00:32:38,110 volcanic flea created feature a violent 849 00:32:42,540 --> 00:32:40,180 volcanic eruption created the debris 850 00:32:44,490 --> 00:32:42,550 that formed this feature it's shaped 851 00:32:46,710 --> 00:32:44,500 like a pancake about 90 meters across 852 00:32:48,660 --> 00:32:46,720 and just a couple meters high here you 853 00:32:51,450 --> 00:32:48,670 can see volcanic rocks all around it 854 00:32:53,820 --> 00:32:51,460 they were probably from lava flows but 855 00:32:55,560 --> 00:32:53,830 we this this deposit home plate was 856 00:32:58,080 --> 00:32:55,570 really a product of very violent 857 00:33:00,540 --> 00:32:58,090 volcanism but for us the most exciting 858 00:33:02,910 --> 00:33:00,550 observation was the discovery of almost 859 00:33:05,070 --> 00:33:02,920 pure silica deposit purely opal and 860 00:33:07,380 --> 00:33:05,080 silica deposits around the perimeter all 861 00:33:09,450 --> 00:33:07,390 the way around this side and down on the 862 00:33:11,940 --> 00:33:09,460 far side as you look at this image we 863 00:33:13,680 --> 00:33:11,950 found the deposits that required liquid 864 00:33:17,190 --> 00:33:13,690 water for their deposition or their 865 00:33:19,260 --> 00:33:17,200 their creation which means now we have 866 00:33:21,060 --> 00:33:19,270 evidence for the volcanic activity 867 00:33:23,070 --> 00:33:21,070 occurring in concert with liquid water 868 00:33:25,650 --> 00:33:23,080 well that's exciting and why is that 869 00:33:26,850 --> 00:33:25,660 exciting because if we look at the earth 870 00:33:29,700 --> 00:33:26,860 and now we're at Yellowstone National 871 00:33:32,340 --> 00:33:29,710 Park the grand prismatic spring a very 872 00:33:34,080 --> 00:33:32,350 large spring at the in Yellowstone and 873 00:33:36,030 --> 00:33:34,090 here you can see a rather large 874 00:33:38,160 --> 00:33:36,040 boardwalk going by it and here is a 10 875 00:33:40,320 --> 00:33:38,170 metre scale here this type of an 876 00:33:44,010 --> 00:33:40,330 environment which we could well now have 877 00:33:45,810 --> 00:33:44,020 evidence for on Mars is a type example 878 00:33:48,720 --> 00:33:45,820 of a habitable environment for microbial 879 00:33:50,510 --> 00:33:48,730 life on the earth here we it's an oasis 880 00:33:53,280 --> 00:33:50,520 obviously you have near surface water 881 00:33:55,050 --> 00:33:53,290 they spring waters bring up chemicals 882 00:33:56,970 --> 00:33:55,060 that could / die provide sources of 883 00:34:00,270 --> 00:33:56,980 energy for life like the sulfur gases 884 00:34:02,010 --> 00:34:00,280 the hydrogen and some even cases that 885 00:34:04,620 --> 00:34:02,020 reduced iron that we see dissolved in 886 00:34:07,470 --> 00:34:04,630 some Springs these can be acted upon by 887 00:34:09,150 --> 00:34:07,480 microbes to obtain energy and if that's 888 00:34:11,550 --> 00:34:09,160 not good enough we have these mineral 889 00:34:14,880 --> 00:34:11,560 deposits like pure silica such as we 890 00:34:17,700 --> 00:34:14,890 have found at at this home plate feature 891 00:34:19,800 --> 00:34:17,710 on Mars that could preserve evidence of 892 00:34:21,630 --> 00:34:19,810 life and I can just call as an example 893 00:34:23,940 --> 00:34:21,640 petrified wood ather sure we're all 894 00:34:26,070 --> 00:34:23,950 familiar with that where ancient tree 895 00:34:28,290 --> 00:34:26,080 trunks have been solicit ID by silica 896 00:34:30,930 --> 00:34:28,300 and you see this beautifully faithful 897 00:34:33,270 --> 00:34:30,940 reproduction of all the woody features 898 00:34:35,370 --> 00:34:33,280 that textures of wood that were once 899 00:34:37,650 --> 00:34:35,380 present there with the tree likewise 900 00:34:39,330 --> 00:34:37,660 silicon can preserve fossils of 901 00:34:41,130 --> 00:34:39,340 microbial life as we've seen at 902 00:34:44,520 --> 00:34:41,140 Yellowstone and also in other ancient 903 00:34:46,440 --> 00:34:44,530 rocks on earth and therefore Hot Springs 904 00:34:49,080 --> 00:34:46,450 can do this for us as well and of course 905 00:34:50,690 --> 00:34:49,090 this hot to cold transitioned from the 906 00:34:52,919 --> 00:34:50,700 spring out to the stream flows 907 00:34:54,960 --> 00:34:52,929 represents a range of conditions that 908 00:34:58,320 --> 00:34:54,970 could sustain a variety of organisms and 909 00:35:00,780 --> 00:34:58,330 now we have found basically a place on 910 00:35:03,320 --> 00:35:00,790 Mars where an environment awfully 911 00:35:06,120 --> 00:35:03,330 similar to this has you know has 912 00:35:07,560 --> 00:35:06,130 potentially occurred and it could have 913 00:35:09,600 --> 00:35:07,570 been potentially habitable in the past 914 00:35:13,200 --> 00:35:09,610 so in this way we're making observations 915 00:35:14,720 --> 00:35:13,210 that advance further towards being able 916 00:35:16,920 --> 00:35:14,730 to establish that we might have had 917 00:35:19,560 --> 00:35:16,930 habitable environments for life on Mars 918 00:35:22,650 --> 00:35:19,570 maybe not life as plants and animals but 919 00:35:23,970 --> 00:35:22,660 life as microorganisms and this is an 920 00:35:25,740 --> 00:35:23,980 image that you can find in the 921 00:35:28,350 --> 00:35:25,750 Smithsonian Museum Natural History 922 00:35:30,780 --> 00:35:28,360 Museum in Washington DC beautiful mural 923 00:35:32,730 --> 00:35:30,790 trying to represent what we think the 924 00:35:34,830 --> 00:35:32,740 early Earth looked like with its 925 00:35:37,230 --> 00:35:34,840 volcanoes and it's standing water and 926 00:35:38,730 --> 00:35:37,240 it's hot springs and so forth and in 927 00:35:39,540 --> 00:35:38,740 many ways you could say that we have 928 00:35:41,550 --> 00:35:39,550 documented 929 00:35:43,890 --> 00:35:41,560 parallel features on Mars that may have 930 00:35:46,050 --> 00:35:43,900 all existed at the same time and so we 931 00:35:47,850 --> 00:35:46,060 really are making progress towards 932 00:35:49,710 --> 00:35:47,860 looking for habitable environments on 933 00:35:51,840 --> 00:35:49,720 Mars these little funny yellowish 934 00:35:54,090 --> 00:35:51,850 features that you see here are an artist 935 00:35:56,280 --> 00:35:54,100 representation of microbial colonies 936 00:35:58,350 --> 00:35:56,290 what we call stromatolites or microbial 937 00:36:00,660 --> 00:35:58,360 reef structures of course we haven't 938 00:36:02,340 --> 00:36:00,670 found those on Mars yet but net we're 939 00:36:04,200 --> 00:36:02,350 beginning to get smarter looking at the 940 00:36:06,480 --> 00:36:04,210 right for the going to the right places 941 00:36:08,910 --> 00:36:06,490 to look for these features and have a 942 00:36:10,830 --> 00:36:08,920 higher chance of finding fossil evidence 943 00:36:12,120 --> 00:36:10,840 not happened yet but we're getting 944 00:36:14,760 --> 00:36:12,130 better at looking in the right 945 00:36:16,380 --> 00:36:14,770 neighborhoods okay so let me now just 946 00:36:18,540 --> 00:36:16,390 return to this block which shows that 947 00:36:20,520 --> 00:36:18,550 you need the water the energy and the 948 00:36:23,460 --> 00:36:20,530 nutrients in order to support life and 949 00:36:24,900 --> 00:36:23,470 now to just raise the bar further okay 950 00:36:27,330 --> 00:36:24,910 me may have found some of these places 951 00:36:29,580 --> 00:36:27,340 but how long did these conditions last 952 00:36:31,530 --> 00:36:29,590 and how much time does life need in 953 00:36:33,750 --> 00:36:31,540 order to get started and to survive 954 00:36:36,540 --> 00:36:33,760 that's a really tough question we've now 955 00:36:38,220 --> 00:36:36,550 got to go to the surface of Mars to a 956 00:36:40,620 --> 00:36:38,230 place where we could be reasonably 957 00:36:42,450 --> 00:36:40,630 convinced that thing's persisted for 958 00:36:44,160 --> 00:36:42,460 let's just stick their neck out and say 959 00:36:45,750 --> 00:36:44,170 you know maybe millions of years you 960 00:36:47,490 --> 00:36:45,760 know you had in habitable conditions 961 00:36:49,620 --> 00:36:47,500 that lasted for a very long time and 962 00:36:52,440 --> 00:36:49,630 that maybe that's adequate then to 963 00:36:54,120 --> 00:36:52,450 support life and so in that regard I'll 964 00:36:56,340 --> 00:36:54,130 move on to the next talk with our 965 00:36:58,380 --> 00:36:56,350 upcoming mission but just before I do 966 00:37:00,570 --> 00:36:58,390 that here's a couple of questions from 967 00:37:02,520 --> 00:37:00,580 what we just talked about what features 968 00:37:04,170 --> 00:37:02,530 were discovered by Opportunity rover at 969 00:37:06,600 --> 00:37:04,180 meridiani planum that indicated that 970 00:37:08,040 --> 00:37:06,610 liquid water once existed there and what 971 00:37:10,380 --> 00:37:08,050 is the evidence that the water we had 972 00:37:12,210 --> 00:37:10,390 sometimes been on the surface okay so 973 00:37:14,820 --> 00:37:12,220 that's the question aimed at the 974 00:37:16,800 --> 00:37:14,830 opportunity rover for spirit what 975 00:37:18,690 --> 00:37:16,810 features did spirit rover finded Gusev 976 00:37:21,510 --> 00:37:18,700 crater that indicated that liquid water 977 00:37:23,640 --> 00:37:21,520 was present and so that's the parallel 978 00:37:25,710 --> 00:37:23,650 question for the spirit rover so that's 979 00:37:30,150 --> 00:37:25,720 for the previous section let's now move 980 00:37:35,190 --> 00:37:30,160 on we are now of course as I give this 981 00:37:37,410 --> 00:37:35,200 talk poised here for to see what the 982 00:37:40,410 --> 00:37:37,420 Mars Science Laboratory will find at the 983 00:37:42,540 --> 00:37:40,420 surface of Mars to continue this sort of 984 00:37:45,780 --> 00:37:42,550 coordinated exploration by orbiters and 985 00:37:49,080 --> 00:37:45,790 el sol by landers of the most promising 986 00:37:51,690 --> 00:37:49,090 places at the surface of Mars and so the 987 00:37:53,370 --> 00:37:51,700 Mars Science Laboratory now along those 988 00:37:55,530 --> 00:37:53,380 lines has benefited 989 00:37:58,170 --> 00:37:55,540 an even more extensive observation of 990 00:38:00,780 --> 00:37:58,180 the surface of Mars by these advanced 991 00:38:02,910 --> 00:38:00,790 orbiters and therefore we have found a 992 00:38:05,940 --> 00:38:02,920 very compelling landing site for this 993 00:38:08,070 --> 00:38:05,950 for this Rover to go to a little couple 994 00:38:10,170 --> 00:38:08,080 of comments about the capability of the 995 00:38:12,330 --> 00:38:10,180 Curiosity rover like the Mars 996 00:38:14,580 --> 00:38:12,340 exploration Rovers it has a very nice 997 00:38:17,130 --> 00:38:14,590 camera set up cameras really to make 998 00:38:18,840 --> 00:38:17,140 those field geology observations that 999 00:38:20,550 --> 00:38:18,850 any geologists would need to make in 1000 00:38:23,310 --> 00:38:20,560 order to define the best places to 1001 00:38:25,170 --> 00:38:23,320 explore it obviously has mobility with 1002 00:38:27,690 --> 00:38:25,180 its wheel system much like the Mars 1003 00:38:29,850 --> 00:38:27,700 exploration Rovers did and also like 1004 00:38:31,560 --> 00:38:29,860 them it has an arm which can look out 1005 00:38:34,110 --> 00:38:31,570 with the hand lens closely at the rocks 1006 00:38:37,320 --> 00:38:34,120 and also do some analyses of these rocks 1007 00:38:39,630 --> 00:38:37,330 for their elemental abundances it also 1008 00:38:41,850 --> 00:38:39,640 though has a very important capability 1009 00:38:43,710 --> 00:38:41,860 to bring samples back and put them 1010 00:38:45,480 --> 00:38:43,720 inside the laboratory which is why we 1011 00:38:47,640 --> 00:38:45,490 call this the Mars Science Laboratory 1012 00:38:50,520 --> 00:38:47,650 mission we have an instrument that you 1013 00:38:52,860 --> 00:38:50,530 can do x-ray analyses to terminals that 1014 00:38:54,870 --> 00:38:52,870 might be present and we also have an 1015 00:38:57,150 --> 00:38:54,880 instrument within the body of this Rover 1016 00:38:59,220 --> 00:38:57,160 that can look at organic compounds if 1017 00:39:01,050 --> 00:38:59,230 they're present or to analyze gases or 1018 00:39:03,450 --> 00:39:01,060 other volatile type species that might 1019 00:39:05,820 --> 00:39:03,460 be present in the samples and so in that 1020 00:39:07,890 --> 00:39:05,830 respect it can do a much more detailed 1021 00:39:10,200 --> 00:39:07,900 analysis of samples than what the Mars 1022 00:39:12,150 --> 00:39:10,210 exploration Rovers did so much bigger 1023 00:39:14,010 --> 00:39:12,160 over this one's about the size of a Jeep 1024 00:39:16,980 --> 00:39:14,020 whereas the others were the size of 1025 00:39:19,140 --> 00:39:16,990 riding lawnmowers looking a little more 1026 00:39:21,600 --> 00:39:19,150 closely and I'll just allude to these 1027 00:39:23,520 --> 00:39:21,610 and move on we see the remote sensing 1028 00:39:24,930 --> 00:39:23,530 instruments the cameras and and the 1029 00:39:26,580 --> 00:39:24,940 chemcam which can actually shoot a 1030 00:39:28,620 --> 00:39:26,590 little laser out and analyze the 1031 00:39:30,270 --> 00:39:28,630 elements in a rock sample that might be 1032 00:39:31,650 --> 00:39:30,280 out in front of the rover so this is 1033 00:39:33,990 --> 00:39:31,660 what we call our remote sensing 1034 00:39:35,730 --> 00:39:34,000 capability then as we get up close and 1035 00:39:37,860 --> 00:39:35,740 personal we can put at the arm out and 1036 00:39:39,720 --> 00:39:37,870 contact the rock with instruments that 1037 00:39:42,300 --> 00:39:39,730 can either look with a hand lens or 1038 00:39:43,980 --> 00:39:42,310 determine the elemental composition if 1039 00:39:46,530 --> 00:39:43,990 we take a sample and put it inside the 1040 00:39:49,200 --> 00:39:46,540 rover we can do as I said chemical and 1041 00:39:51,210 --> 00:39:49,210 isotopic measurements of organic matter 1042 00:39:52,470 --> 00:39:51,220 or gases or whatever and also with the 1043 00:39:54,570 --> 00:39:52,480 other instrument look at the minerals 1044 00:39:57,840 --> 00:39:54,580 and then of course this is also like a 1045 00:40:01,230 --> 00:39:57,850 little roving weather station it can not 1046 00:40:02,880 --> 00:40:01,240 only do meteorology of what the climate 1047 00:40:06,210 --> 00:40:02,890 is are the weather is like at the moment 1048 00:40:07,320 --> 00:40:06,220 but it actually can analyze radiation at 1049 00:40:10,290 --> 00:40:07,330 the field as well 1050 00:40:11,940 --> 00:40:10,300 subsurface availability of water of 1051 00:40:13,890 --> 00:40:11,950 hydrogen actually so a very 1052 00:40:16,440 --> 00:40:13,900 sophisticated Rover really looking 1053 00:40:19,380 --> 00:40:16,450 forward to these analyses the mission 1054 00:40:20,910 --> 00:40:19,390 overview of how it gets there of course 1055 00:40:24,000 --> 00:40:20,920 as we launch it from the earth this 1056 00:40:27,360 --> 00:40:24,010 occurred in November actually November 1057 00:40:29,070 --> 00:40:27,370 of 2011 as I give this talk we're 1058 00:40:31,710 --> 00:40:29,080 currently cruising towards Mars to 1059 00:40:33,180 --> 00:40:31,720 arrive august six east coast time then 1060 00:40:35,610 --> 00:40:33,190 we go through an entry descent and 1061 00:40:38,190 --> 00:40:35,620 landing phase and for this I'd like to 1062 00:40:41,460 --> 00:40:38,200 just show a couple of videos the first 1063 00:40:43,040 --> 00:40:41,470 video and yeah let's go through these 1064 00:40:46,800 --> 00:40:43,050 and these are available on the Mars 1065 00:40:49,650 --> 00:40:46,810 Science Laboratory website what we're 1066 00:40:52,190 --> 00:40:49,660 seeing now is the launch that occurred 1067 00:40:56,010 --> 00:40:52,200 on the saturday after thanksgiving 2011 1068 00:40:57,840 --> 00:40:56,020 this is an atlas 5 rocket the fat part 1069 00:41:01,110 --> 00:40:57,850 at the top of the rocket is the fairing 1070 00:41:03,390 --> 00:41:01,120 that include encloses the rover itself 1071 00:41:05,550 --> 00:41:03,400 stand the entry descent stuff here now 1072 00:41:07,500 --> 00:41:05,560 we see the blast-off which is a 1073 00:41:10,050 --> 00:41:07,510 combination of liquid propulsion engines 1074 00:41:11,520 --> 00:41:10,060 and solid engines that give the thrust 1075 00:41:13,650 --> 00:41:11,530 necessary to get up through the lower 1076 00:41:16,020 --> 00:41:13,660 part of the earth's atmosphere as you 1077 00:41:18,360 --> 00:41:16,030 can see it was a partly cloudy day some 1078 00:41:20,550 --> 00:41:18,370 of us said better vantage points than 1079 00:41:22,080 --> 00:41:20,560 the other but these this video that 1080 00:41:24,300 --> 00:41:22,090 you're looking really shows the best of 1081 00:41:26,190 --> 00:41:24,310 all worlds vantage points from several 1082 00:41:28,710 --> 00:41:26,200 places using telescopes to give you a 1083 00:41:32,250 --> 00:41:28,720 sense of the various stages in the 1084 00:41:34,140 --> 00:41:32,260 launch of this Atlas 5 rocket the first 1085 00:41:36,360 --> 00:41:34,150 thing that will major event that happens 1086 00:41:38,340 --> 00:41:36,370 after the ignition and the launch will 1087 00:41:40,500 --> 00:41:38,350 be the solid Rockets that you see sort 1088 00:41:42,540 --> 00:41:40,510 of around the back of the rocket being 1089 00:41:44,550 --> 00:41:42,550 ejected once they've done their work 1090 00:41:46,980 --> 00:41:44,560 here we're still looking at the main 1091 00:41:49,140 --> 00:41:46,990 engines thrust and of course very 1092 00:41:53,850 --> 00:41:49,150 quickly getting the rock up to high 1093 00:41:55,860 --> 00:41:53,860 altitudes this image probably taken by 1094 00:41:58,440 --> 00:41:55,870 it from a telescope it's down range from 1095 00:41:59,880 --> 00:41:58,450 the launching pad those of us who 1096 00:42:02,340 --> 00:41:59,890 witnessed the launch we're just amazed 1097 00:42:05,850 --> 00:42:02,350 to see these later it's a beautiful set 1098 00:42:07,350 --> 00:42:05,860 of images and I think now as and also as 1099 00:42:08,730 --> 00:42:07,360 this gets higher and higher in the 1100 00:42:11,010 --> 00:42:08,740 atmosphere you'll notice that the tail 1101 00:42:13,520 --> 00:42:11,020 the exhaust is spreading out as the 1102 00:42:16,800 --> 00:42:13,530 atmospheric pressure decreases that 1103 00:42:19,320 --> 00:42:16,810 exhaust tail gets wider and wider now 1104 00:42:21,120 --> 00:42:19,330 and see a beautiful close-up of you can 1105 00:42:22,789 --> 00:42:21,130 see the solid Rockets are still firing 1106 00:42:26,160 --> 00:42:22,799 around the perimeter of the main rocket 1107 00:42:30,509 --> 00:42:26,170 and the tale begins to widen as the 1108 00:42:32,549 --> 00:42:30,519 atmospheric pressure decreases so now is 1109 00:42:35,579 --> 00:42:32,559 you can almost begin to definitely see 1110 00:42:37,650 --> 00:42:35,589 the flaring now and you still see the 1111 00:42:39,480 --> 00:42:37,660 glow of the solid Rockets but now 1112 00:42:41,609 --> 00:42:39,490 they're beginning to lose steam as they 1113 00:42:43,980 --> 00:42:41,619 use up their propellant and you can 1114 00:42:45,900 --> 00:42:43,990 still see the liquid Rockets firing away 1115 00:42:48,120 --> 00:42:45,910 there we're now to the point where we 1116 00:42:50,370 --> 00:42:48,130 really need to get rid of the weight of 1117 00:42:52,559 --> 00:42:50,380 those solid rockets which you'll see 1118 00:42:57,329 --> 00:42:52,569 them peeling off shortly here as they 1119 00:42:58,920 --> 00:42:57,339 there's goes there they go okay and of 1120 00:43:01,650 --> 00:42:58,930 course we do this to make this a much 1121 00:43:03,930 --> 00:43:01,660 more weight efficient spacecraft and the 1122 00:43:06,539 --> 00:43:03,940 liquid Rockets continue to burn this 1123 00:43:08,789 --> 00:43:06,549 will this you'll continue to see the 1124 00:43:11,339 --> 00:43:08,799 tail flare out and the rocket gets 1125 00:43:13,799 --> 00:43:11,349 smaller and harder to see and I think 1126 00:43:16,859 --> 00:43:13,809 perhaps at this point we could just 1127 00:43:19,920 --> 00:43:16,869 transition from this to the next video 1128 00:43:22,259 --> 00:43:19,930 which is now that that has gotten into 1129 00:43:25,319 --> 00:43:22,269 an orbit it actually never orbits the 1130 00:43:28,499 --> 00:43:25,329 earth completely we get up into an 1131 00:43:31,079 --> 00:43:28,509 orbital altitude but then we cruise out 1132 00:43:33,359 --> 00:43:31,089 over across Africa into the Indian Ocean 1133 00:43:35,490 --> 00:43:33,369 and this is sort of where we are now 1134 00:43:37,410 --> 00:43:35,500 we're now over the Indian Ocean you can 1135 00:43:38,490 --> 00:43:37,420 see now the upper stage is just fired to 1136 00:43:41,579 --> 00:43:38,500 make sure we're in the right trajectory 1137 00:43:43,559 --> 00:43:41,589 it is now positioning the spacecraft in 1138 00:43:46,109 --> 00:43:43,569 order to be inserted out of Earth orbit 1139 00:43:48,210 --> 00:43:46,119 and towards Mars and so you can see now 1140 00:43:49,890 --> 00:43:48,220 it's taken on this angle you can see the 1141 00:43:51,630 --> 00:43:49,900 little rockets firing to make sure and 1142 00:43:54,390 --> 00:43:51,640 also you can see we're giving a nice 1143 00:43:55,890 --> 00:43:54,400 slow spin this is spin stabilization 1144 00:43:58,440 --> 00:43:55,900 once that's done we get rid of that 1145 00:44:00,480 --> 00:43:58,450 boost that upper stage rocket and now 1146 00:44:03,120 --> 00:44:00,490 you're looking at the actual spacecraft 1147 00:44:05,309 --> 00:44:03,130 that is heading off to Mars consists of 1148 00:44:07,079 --> 00:44:05,319 two things it consists of what's called 1149 00:44:08,700 --> 00:44:07,089 the cruise stage that what you're seeing 1150 00:44:11,309 --> 00:44:08,710 now which are the solar panels that 1151 00:44:14,130 --> 00:44:11,319 provide power to the spacecraft is its 1152 00:44:16,470 --> 00:44:14,140 cruising to Mars and in the front as 1153 00:44:18,480 --> 00:44:16,480 sort of clamshells safe shaped enclosure 1154 00:44:20,730 --> 00:44:18,490 than it actually contains the rover and 1155 00:44:22,970 --> 00:44:20,740 the entry descent landing hardware and 1156 00:44:26,400 --> 00:44:22,980 so eight and a half months later and 1157 00:44:28,620 --> 00:44:26,410 that would be now as in August of 2012 1158 00:44:30,210 --> 00:44:28,630 we dumped the cruise stage and pay 1159 00:44:32,099 --> 00:44:30,220 tribute to all the engineers who 1160 00:44:34,860 --> 00:44:32,109 designed that it's always a very solemn 1161 00:44:36,750 --> 00:44:34,870 moment and now the 1162 00:44:39,450 --> 00:44:36,760 entry vehicle is going in and of course 1163 00:44:42,000 --> 00:44:39,460 we have to now d accelerate from 13,000 1164 00:44:44,400 --> 00:44:42,010 miles an hour down to a much lower speed 1165 00:44:46,440 --> 00:44:44,410 where we can deploy a parachute so this 1166 00:44:48,300 --> 00:44:46,450 now is it accelerates towards Mars it 1167 00:44:50,640 --> 00:44:48,310 actually reaches that Peaks velocity of 1168 00:44:52,410 --> 00:44:50,650 13,000 miles an hour you can see how 1169 00:44:54,390 --> 00:44:52,420 it's maintaining attitude control with 1170 00:44:56,370 --> 00:44:54,400 those little firing to the Jets this 1171 00:44:57,870 --> 00:44:56,380 tremendous heat that occurs is the 1172 00:44:59,940 --> 00:44:57,880 friction of the atmosphere interacts 1173 00:45:01,740 --> 00:44:59,950 with that each yield and it's a great 1174 00:45:03,930 --> 00:45:01,750 way to slow it down we're just D 1175 00:45:05,430 --> 00:45:03,940 accelerating right now but in a way that 1176 00:45:07,710 --> 00:45:05,440 doesn't burn up the spacecraft we 1177 00:45:09,510 --> 00:45:07,720 learned early on how to design these 1178 00:45:11,580 --> 00:45:09,520 entry vehicles so that you can actually 1179 00:45:14,040 --> 00:45:11,590 survive this coming in through the 1180 00:45:15,510 --> 00:45:14,050 atmosphere some point then we've gotten 1181 00:45:18,000 --> 00:45:15,520 down to a speed that's slow enough to 1182 00:45:20,280 --> 00:45:18,010 deploy deploy the parachute and we don't 1183 00:45:23,160 --> 00:45:20,290 need that heat shield anymore it's done 1184 00:45:25,650 --> 00:45:23,170 its job and once we get that parachute 1185 00:45:27,840 --> 00:45:25,660 out and it's deploying it I've almost 1186 00:45:30,510 --> 00:45:27,850 Mach 2 it's still over a thousand miles 1187 00:45:32,640 --> 00:45:30,520 an hour we can dump the heat shield and 1188 00:45:35,340 --> 00:45:32,650 now there's a radar on the spacecraft 1189 00:45:36,960 --> 00:45:35,350 can determine the location of the ground 1190 00:45:38,340 --> 00:45:36,970 and this determines the timing of 1191 00:45:40,530 --> 00:45:38,350 everything of that you're going to see 1192 00:45:43,110 --> 00:45:40,540 from here to the surface for example 1193 00:45:44,790 --> 00:45:43,120 dropping of what we call the sky crane 1194 00:45:47,730 --> 00:45:44,800 this is actually a descent rocket 1195 00:45:50,450 --> 00:45:47,740 assembly that takes us down and slows us 1196 00:45:53,640 --> 00:45:50,460 down as we go to the surface do a very 1197 00:45:56,310 --> 00:45:53,650 modest speed to where within a few 1198 00:46:00,090 --> 00:45:56,320 hundred meters of the surface we can now 1199 00:46:02,430 --> 00:46:00,100 lower the rover down from the descent 1200 00:46:04,620 --> 00:46:02,440 rocket the sky crane and that's hence 1201 00:46:07,190 --> 00:46:04,630 the name crane it's basically got a 1202 00:46:09,750 --> 00:46:07,200 tether that it can use to lower the 1203 00:46:11,520 --> 00:46:09,760 rover down and here you see a little 1204 00:46:13,290 --> 00:46:11,530 close-up of the camera as it's looking 1205 00:46:15,600 --> 00:46:13,300 at the surface the cameras mounted on 1206 00:46:17,400 --> 00:46:15,610 the rover it's telling us now with the 1207 00:46:19,020 --> 00:46:17,410 surface around the landing site looks 1208 00:46:20,640 --> 00:46:19,030 like this will be quite useful once we 1209 00:46:23,070 --> 00:46:20,650 get down and start driving around here 1210 00:46:26,550 --> 00:46:23,080 you see now the sky crane lowering on a 1211 00:46:28,350 --> 00:46:26,560 tether the rover it now has sensors 1212 00:46:30,720 --> 00:46:28,360 which will tell it when that thing then 1213 00:46:31,890 --> 00:46:30,730 that Rover touches the ground and when 1214 00:46:33,810 --> 00:46:31,900 that touches the ground that will 1215 00:46:37,020 --> 00:46:33,820 trigger what you see happening next year 1216 00:46:38,940 --> 00:46:37,030 the sky crane now slowly lowering the 1217 00:46:40,470 --> 00:46:38,950 rover to the surface we actually put six 1218 00:46:42,570 --> 00:46:40,480 wheels on the ground as part of the 1219 00:46:45,000 --> 00:46:42,580 landing sequence when it senses that 1220 00:46:47,330 --> 00:46:45,010 it's landed it cuts the cables and flies 1221 00:46:48,900 --> 00:46:47,340 off in its program to fly far away and 1222 00:46:50,970 --> 00:46:48,910 frankly crash 1223 00:46:53,160 --> 00:46:50,980 so that it doesn't interfere with the 1224 00:46:55,740 --> 00:46:53,170 mission here we now have the rover on 1225 00:46:57,450 --> 00:46:55,750 the ground and unlike with the Mars 1226 00:47:00,060 --> 00:46:57,460 rovers that had to drive off a platform 1227 00:47:02,520 --> 00:47:00,070 we are on the ground and ready to go 1228 00:47:03,870 --> 00:47:02,530 however for the first several weeks we 1229 00:47:05,850 --> 00:47:03,880 will be checking out all the very 1230 00:47:07,590 --> 00:47:05,860 complicated systems on this Rover and 1231 00:47:09,630 --> 00:47:07,600 it'll take us a while before we can 1232 00:47:11,160 --> 00:47:09,640 actually strike out and explore the 1233 00:47:14,460 --> 00:47:11,170 countryside but this shows it in the 1234 00:47:16,800 --> 00:47:14,470 video pretty much a sequence that you 1235 00:47:19,410 --> 00:47:16,810 could expect us to do once we get moving 1236 00:47:22,890 --> 00:47:19,420 on Mars looking around figuring out the 1237 00:47:24,540 --> 00:47:22,900 best places to go and then driving as 1238 00:47:26,130 --> 00:47:24,550 you can see from the tracks here up to 1239 00:47:28,500 --> 00:47:26,140 something that looks quite promising a 1240 00:47:30,150 --> 00:47:28,510 layer of rocks here we have our little 1241 00:47:32,700 --> 00:47:30,160 laser on board you'll see the little 1242 00:47:34,200 --> 00:47:32,710 light there is it fires out and hits the 1243 00:47:36,240 --> 00:47:34,210 rock first of all we're looking at it 1244 00:47:38,520 --> 00:47:36,250 with our camera okay that's a good place 1245 00:47:40,410 --> 00:47:38,530 to shoot our laser there you can see it 1246 00:47:42,990 --> 00:47:40,420 a little flickering light that is 1247 00:47:45,270 --> 00:47:43,000 actually analyzing the rock there it 1248 00:47:46,800 --> 00:47:45,280 looks promising and it's so promising 1249 00:47:48,810 --> 00:47:46,810 that we're now going to drive up and put 1250 00:47:51,090 --> 00:47:48,820 our arm out you can see now the arm of 1251 00:47:52,920 --> 00:47:51,100 the rover being put out first to do a 1252 00:47:55,320 --> 00:47:52,930 close-up observation of the rock with 1253 00:47:57,600 --> 00:47:55,330 our microscopic imager but then to drill 1254 00:47:59,160 --> 00:47:57,610 into the rock and take a sample to bring 1255 00:48:01,560 --> 00:47:59,170 back to our laboratory and I think this 1256 00:48:03,930 --> 00:48:01,570 is just jumping to the drill where we 1257 00:48:05,870 --> 00:48:03,940 now have a percussion drill that can set 1258 00:48:10,140 --> 00:48:05,880 of rotates and drills into the rock and 1259 00:48:11,670 --> 00:48:10,150 obtains a sample for the you know for 1260 00:48:13,890 --> 00:48:11,680 the laboratory and now we have put this 1261 00:48:15,570 --> 00:48:13,900 powder that's come from the drill into 1262 00:48:18,480 --> 00:48:15,580 our x-ray diffraction instrument called 1263 00:48:20,850 --> 00:48:18,490 chemin and the little depiction here you 1264 00:48:22,260 --> 00:48:20,860 see is of x rays hitting the sample you 1265 00:48:24,090 --> 00:48:22,270 wouldn't actually be able to see this 1266 00:48:25,950 --> 00:48:24,100 but the light showing it here just 1267 00:48:28,130 --> 00:48:25,960 illustrates it and as it hits the 1268 00:48:31,440 --> 00:48:28,140 various layers of atoms in the mineral 1269 00:48:33,450 --> 00:48:31,450 these x-rays are bounced off at various 1270 00:48:36,270 --> 00:48:33,460 characteristic angles to form these ring 1271 00:48:37,830 --> 00:48:36,280 patterns that you see and the spacing of 1272 00:48:40,470 --> 00:48:37,840 those ring patterns and their relative 1273 00:48:42,270 --> 00:48:40,480 intensities are a fingerprint for the 1274 00:48:45,240 --> 00:48:42,280 actual mineral that's present and it's a 1275 00:48:46,920 --> 00:48:45,250 very very diagnostic way of determining 1276 00:48:48,540 --> 00:48:46,930 the minerals that are present even if we 1277 00:48:50,790 --> 00:48:48,550 have never discovered a mineral before 1278 00:48:53,750 --> 00:48:50,800 we can figure out what it is by this 1279 00:48:56,520 --> 00:48:53,760 analysis and so that's a little bit of a 1280 00:48:58,950 --> 00:48:56,530 overview of the capabilities that this 1281 00:49:01,740 --> 00:48:58,960 Rover can do the question then is where 1282 00:49:02,880 --> 00:49:01,750 are we going with that and that is to 1283 00:49:06,120 --> 00:49:02,890 Gale Crater and you can 1284 00:49:09,059 --> 00:49:06,130 here over on the right side of the of 1285 00:49:11,279 --> 00:49:09,069 the Mercator map that I have shown 1286 00:49:13,250 --> 00:49:11,289 several times a crater that's located 1287 00:49:15,960 --> 00:49:13,260 right at the dichotomy boundary between 1288 00:49:19,890 --> 00:49:15,970 the southern highlands in the northern 1289 00:49:21,329 --> 00:49:19,900 lowlands Gale Crater as with Gusev 1290 00:49:23,849 --> 00:49:21,339 crater showed evidence that liquid water 1291 00:49:26,460 --> 00:49:23,859 might have been there in the past here 1292 00:49:28,589 --> 00:49:26,470 is a close-up of that crater showing 1293 00:49:31,710 --> 00:49:28,599 that it's it's pretty good size it's 150 1294 00:49:34,200 --> 00:49:31,720 5 kilometers in diameter but it has 1295 00:49:35,609 --> 00:49:34,210 quite a quite a relief inside of it if 1296 00:49:37,019 --> 00:49:35,619 you look at the little scale bar over 1297 00:49:40,740 --> 00:49:37,029 here you can see that it's several 1298 00:49:43,289 --> 00:49:40,750 kilometers in depth and unlike Gusev 1299 00:49:46,170 --> 00:49:43,299 crater we can look at this with our more 1300 00:49:48,599 --> 00:49:46,180 advanced orbiters and say that the 1301 00:49:50,880 --> 00:49:48,609 surface is not covered with lava flows 1302 00:49:52,500 --> 00:49:50,890 it's actually covered with deposits that 1303 00:49:54,299 --> 00:49:52,510 may well have borne the evidence of 1304 00:49:56,930 --> 00:49:54,309 liquid water so right there we have an 1305 00:49:59,099 --> 00:49:56,940 advantage over Gusev crater here at Gale 1306 00:50:02,339 --> 00:49:59,109 and the other interesting thing about 1307 00:50:04,529 --> 00:50:02,349 Gale again it's about 155 kilometers 1308 00:50:06,930 --> 00:50:04,539 across it has the central mound in the 1309 00:50:09,180 --> 00:50:06,940 middle and it has layers in this in the 1310 00:50:11,249 --> 00:50:09,190 mound and it indicates indicated that 1311 00:50:13,920 --> 00:50:11,259 these layers formed perhaps over a very 1312 00:50:15,420 --> 00:50:13,930 extended period of time and so the 1313 00:50:17,640 --> 00:50:15,430 question then is how much as water 1314 00:50:21,210 --> 00:50:17,650 influenced these layers and what kind of 1315 00:50:22,980 --> 00:50:21,220 story could we reconstruct about the 1316 00:50:25,079 --> 00:50:22,990 history of the the deposition of these 1317 00:50:30,089 --> 00:50:25,089 layers where I'm showing the arrow now 1318 00:50:31,829 --> 00:50:30,099 is our landing site at Gale where it's 1319 00:50:33,990 --> 00:50:31,839 safe to land you can see it's relatively 1320 00:50:35,999 --> 00:50:34,000 flat and then so we land where it's safe 1321 00:50:37,890 --> 00:50:36,009 and then we drive over to where it's 1322 00:50:40,620 --> 00:50:37,900 it's scientifically interesting namely 1323 00:50:43,339 --> 00:50:40,630 to begin to analyze the lower layers of 1324 00:50:45,960 --> 00:50:43,349 this mound in the center of Gale Crater 1325 00:50:48,779 --> 00:50:45,970 what's exciting about it is illustrated 1326 00:50:50,460 --> 00:50:48,789 in this diagram you're looking at the 1327 00:50:52,499 --> 00:50:50,470 lower part of the mound here where that 1328 00:50:53,999 --> 00:50:52,509 safe areas to the upper left and the 1329 00:50:56,099 --> 00:50:54,009 upper part of the mound is to the lower 1330 00:50:58,200 --> 00:50:56,109 right so you're looking at a slope sort 1331 00:51:00,809 --> 00:50:58,210 of going from the lower right down to 1332 00:51:02,640 --> 00:51:00,819 the upper left these colors are meant to 1333 00:51:04,980 --> 00:51:02,650 represent different minerals and there's 1334 00:51:07,230 --> 00:51:04,990 listed here on the left side all of 1335 00:51:09,630 --> 00:51:07,240 these minerals are formed by some kind 1336 00:51:12,480 --> 00:51:09,640 of interaction with water the most easy 1337 00:51:15,509 --> 00:51:12,490 ones to see about that are the clay 1338 00:51:16,560 --> 00:51:15,519 minerals which are shown here in sort of 1339 00:51:18,420 --> 00:51:16,570 the light blue 1340 00:51:20,400 --> 00:51:18,430 color in their scale so you can see that 1341 00:51:22,110 --> 00:51:20,410 there are clay minerals here but also 1342 00:51:23,940 --> 00:51:22,120 there's other minerals like sulfates 1343 00:51:26,760 --> 00:51:23,950 just like the ones that opportunity 1344 00:51:28,860 --> 00:51:26,770 found at meridiani indicating also water 1345 00:51:31,640 --> 00:51:28,870 interactions keys right as a sulfate 1346 00:51:34,710 --> 00:51:31,650 mineral as are these darker blue 1347 00:51:36,810 --> 00:51:34,720 indicated minerals here and so and then 1348 00:51:39,060 --> 00:51:36,820 we have plays in the form of nitrogen 1349 00:51:42,330 --> 00:51:39,070 what we call smectite plays shown here 1350 00:51:43,980 --> 00:51:42,340 in yellow so we have layers that are 1351 00:51:46,350 --> 00:51:43,990 very rich in minerals that right at the 1352 00:51:48,690 --> 00:51:46,360 get-go we can tell you involve liquid 1353 00:51:50,760 --> 00:51:48,700 water and so this is very exciting for 1354 00:51:52,980 --> 00:51:50,770 us as a target to go and actually 1355 00:51:55,200 --> 00:51:52,990 explore so this will be the first time 1356 00:51:57,240 --> 00:51:55,210 now where we have a rover that can go to 1357 00:51:59,130 --> 00:51:57,250 a place and see clay minerals that were 1358 00:52:00,780 --> 00:51:59,140 identified from the orbit and that's 1359 00:52:03,570 --> 00:52:00,790 because the clay minerals were found 1360 00:52:06,180 --> 00:52:03,580 long after the mars to Mars rovers were 1361 00:52:08,240 --> 00:52:06,190 launched and landed and so now we have 1362 00:52:10,620 --> 00:52:08,250 this unique opportunity really to pair a 1363 00:52:13,950 --> 00:52:10,630 compelling orbital observation with the 1364 00:52:16,080 --> 00:52:13,960 landed exploration and so we have this 1365 00:52:18,090 --> 00:52:16,090 mound showing very interesting minerals 1366 00:52:20,430 --> 00:52:18,100 and as if that's not enough these blue 1367 00:52:22,290 --> 00:52:20,440 features that you see here represent 1368 00:52:24,300 --> 00:52:22,300 evidences of standing water that 1369 00:52:26,670 --> 00:52:24,310 occurred even after this mound was 1370 00:52:28,200 --> 00:52:26,680 formed so the mound tell us that tells 1371 00:52:30,300 --> 00:52:28,210 us that at one point this crater was 1372 00:52:32,400 --> 00:52:30,310 completely filled with sediments then 1373 00:52:34,320 --> 00:52:32,410 the sub most some of the sediments were 1374 00:52:35,880 --> 00:52:34,330 taken away by some process and we were 1375 00:52:38,600 --> 00:52:35,890 compelled to think that it actually may 1376 00:52:40,590 --> 00:52:38,610 have been wind that did this and so a 1377 00:52:42,090 --> 00:52:40,600 considerable period of time must have 1378 00:52:44,580 --> 00:52:42,100 passed while all this was happening and 1379 00:52:46,380 --> 00:52:44,590 then after that we have evidence that 1380 00:52:49,110 --> 00:52:46,390 water was standing in this sort of moat 1381 00:52:51,180 --> 00:52:49,120 like area around the perimeter of the of 1382 00:52:52,740 --> 00:52:51,190 the central mound and so we have 1383 00:52:54,810 --> 00:52:52,750 evidence that water was involved in the 1384 00:52:56,580 --> 00:52:54,820 formation of the mound the time pass for 1385 00:52:58,770 --> 00:52:56,590 that mound to be eroded down or for the 1386 00:53:00,990 --> 00:52:58,780 sediments to be removed to reveal the 1387 00:53:02,430 --> 00:53:01,000 mound and then water that formed in the 1388 00:53:05,700 --> 00:53:02,440 moat surrounding the mound so this 1389 00:53:07,170 --> 00:53:05,710 perhaps is our most compelling site for 1390 00:53:08,760 --> 00:53:07,180 the argument that liquid water much a 1391 00:53:11,190 --> 00:53:08,770 person must have persisted over an 1392 00:53:13,380 --> 00:53:11,200 extended period of time so maybe this is 1393 00:53:15,210 --> 00:53:13,390 really one of the best places to go to 1394 00:53:17,490 --> 00:53:15,220 really address the question about a 1395 00:53:19,200 --> 00:53:17,500 habitable environment occurring on early 1396 00:53:21,480 --> 00:53:19,210 Mars and so we're very excited about 1397 00:53:23,070 --> 00:53:21,490 that here's another view that's similar 1398 00:53:25,680 --> 00:53:23,080 to the one I showed earlier the landing 1399 00:53:29,460 --> 00:53:25,690 site the little green squeal here 1400 00:53:30,420 --> 00:53:29,470 showing the Traverse that we would take 1401 00:53:32,480 --> 00:53:30,430 up through the lower man 1402 00:53:35,099 --> 00:53:32,490 to explore some of those very 1403 00:53:37,200 --> 00:53:35,109 interesting clay layers and sulfate 1404 00:53:38,700 --> 00:53:37,210 layers to really see what kind of story 1405 00:53:40,500 --> 00:53:38,710 they can tell us about this early 1406 00:53:42,599 --> 00:53:40,510 environment an environment that may have 1407 00:53:46,349 --> 00:53:42,609 persisted for millions of years as best 1408 00:53:47,790 --> 00:53:46,359 as we can tell and this just shows sort 1409 00:53:49,740 --> 00:53:47,800 of the distance that we have to drive 1410 00:53:51,960 --> 00:53:49,750 from where we land assuming that we land 1411 00:53:54,030 --> 00:53:51,970 in the middle of the safe area and the 1412 00:53:56,579 --> 00:53:54,040 elevation in kilometers that we don't 1413 00:53:58,170 --> 00:53:56,589 really have to climb very much compared 1414 00:54:00,120 --> 00:53:58,180 to the distance we're driving to get to 1415 00:54:01,770 --> 00:54:00,130 some of these very interesting deposits 1416 00:54:04,290 --> 00:54:01,780 so even though the mound looks 1417 00:54:06,240 --> 00:54:04,300 intimidating at first our analyses from 1418 00:54:09,359 --> 00:54:06,250 orbit indicate that we should be able to 1419 00:54:10,740 --> 00:54:09,369 achieve these several of these very 1420 00:54:13,200 --> 00:54:10,750 interesting sites within a reasonable 1421 00:54:15,270 --> 00:54:13,210 life time period of time in the mission 1422 00:54:18,089 --> 00:54:15,280 and at elevations that are not that 1423 00:54:19,829 --> 00:54:18,099 challenging to attain this is an 1424 00:54:21,359 --> 00:54:19,839 interesting view showing some of the 1425 00:54:22,950 --> 00:54:21,369 deposits that were formed perhaps 1426 00:54:26,130 --> 00:54:22,960 associated with those lakes that were in 1427 00:54:27,630 --> 00:54:26,140 the moats this area around the base of 1428 00:54:29,910 --> 00:54:27,640 the mound and then going up into the 1429 00:54:32,220 --> 00:54:29,920 mound itself very interesting terrain 1430 00:54:35,130 --> 00:54:32,230 that the rover would traverse sort of as 1431 00:54:37,109 --> 00:54:35,140 my arrow indicates here to interrogate 1432 00:54:38,430 --> 00:54:37,119 these different layers to see what story 1433 00:54:40,650 --> 00:54:38,440 they can tell about that early 1434 00:54:42,990 --> 00:54:40,660 environment and so it's very it should 1435 00:54:45,390 --> 00:54:43,000 be a very visually compelling mission 1436 00:54:47,339 --> 00:54:45,400 this is created from orbital images that 1437 00:54:49,200 --> 00:54:47,349 allow us to do a stereo reconstruction 1438 00:54:50,490 --> 00:54:49,210 of what the surface looks like but of 1439 00:54:52,109 --> 00:54:50,500 course we'll get much more compelling 1440 00:54:55,410 --> 00:54:52,119 images once we're on the ground with our 1441 00:54:57,630 --> 00:54:55,420 Rover again just to recapitulate the 1442 00:55:00,120 --> 00:54:57,640 kind of Traverse that we might take as 1443 00:55:02,130 --> 00:55:00,130 we drive along driving up into the mound 1444 00:55:03,839 --> 00:55:02,140 and encountering as these colors 1445 00:55:05,520 --> 00:55:03,849 indicate some of these very interesting 1446 00:55:07,740 --> 00:55:05,530 minerals that could tell us the story 1447 00:55:10,650 --> 00:55:07,750 about the early environment in Gale 1448 00:55:11,940 --> 00:55:10,660 Crater going up even further you can 1449 00:55:13,349 --> 00:55:11,950 imagine what the scenery is going to 1450 00:55:15,839 --> 00:55:13,359 look like as we drive up into this 1451 00:55:17,400 --> 00:55:15,849 Canyon and we begin to encounter stream 1452 00:55:19,680 --> 00:55:17,410 type deposits that are bringing 1453 00:55:21,329 --> 00:55:19,690 materials down from an upper part of the 1454 00:55:24,059 --> 00:55:21,339 mound that we may never be able to visit 1455 00:55:25,349 --> 00:55:24,069 directly but we can analyze based on the 1456 00:55:28,079 --> 00:55:25,359 material that has been brought down by 1457 00:55:29,789 --> 00:55:28,089 this stream channel so i mean we could 1458 00:55:32,250 --> 00:55:29,799 be reading millions and millions of 1459 00:55:35,700 --> 00:55:32,260 years of history by traversing in a very 1460 00:55:37,589 --> 00:55:35,710 sort of guided way up the side of the 1461 00:55:40,650 --> 00:55:37,599 flanks of this mound so we're very 1462 00:55:42,480 --> 00:55:40,660 excited about this site and and the 1463 00:55:44,069 --> 00:55:42,490 capabilities at the rover brings to it 1464 00:55:46,349 --> 00:55:44,079 and 1465 00:55:49,079 --> 00:55:46,359 just to sort of finish this off we can 1466 00:55:51,259 --> 00:55:49,089 compel compare the gale mound here sort 1467 00:55:53,519 --> 00:55:51,269 of illustrated on the right with the 1468 00:55:56,099 --> 00:55:53,529 sequence of rocks that you could see at 1469 00:55:58,469 --> 00:55:56,109 the Grand Canyon in Arizona and it's a 1470 00:56:00,390 --> 00:55:58,479 visually compelling set of rocks to look 1471 00:56:03,359 --> 00:56:00,400 at as anybody who's gone to that park 1472 00:56:06,299 --> 00:56:03,369 and a test but it also contains an 1473 00:56:08,190 --> 00:56:06,309 amazing record of Earth history that 1474 00:56:10,499 --> 00:56:08,200 spans hundreds of millions of years and 1475 00:56:13,170 --> 00:56:10,509 that's the point perhaps Gale also 1476 00:56:14,279 --> 00:56:13,180 contains a remarkably informative record 1477 00:56:17,400 --> 00:56:14,289 and as you can see here it actually 1478 00:56:20,039 --> 00:56:17,410 continues up even higher a parallel 1479 00:56:21,599 --> 00:56:20,049 record of a period of Mars history that 1480 00:56:23,309 --> 00:56:21,609 is very relevant to our search for 1481 00:56:25,349 --> 00:56:23,319 habitable environments in life on Mars 1482 00:56:27,479 --> 00:56:25,359 and so I think this comparison with 1483 00:56:29,459 --> 00:56:27,489 Grand Canyon illustrates our level of 1484 00:56:32,039 --> 00:56:29,469 excitement and anticipation of the per 1485 00:56:34,650 --> 00:56:32,049 this mission and again the point to be 1486 00:56:37,079 --> 00:56:34,660 being to try to reconstruct what an 1487 00:56:38,969 --> 00:56:37,089 early environment in Mars might be might 1488 00:56:41,069 --> 00:56:38,979 have been like analogous to our efforts 1489 00:56:43,109 --> 00:56:41,079 in the past to reconstruct early Earth 1490 00:56:44,759 --> 00:56:43,119 environments with implications for 1491 00:56:46,739 --> 00:56:44,769 understanding better the early history 1492 00:56:49,259 --> 00:56:46,749 of our biosphere and of course 1493 00:56:51,209 --> 00:56:49,269 ultimately by finding the right time of 1494 00:56:53,729 --> 00:56:51,219 sight and making the kind of compelling 1495 00:56:56,219 --> 00:56:53,739 observations that we feel the upper that 1496 00:56:58,259 --> 00:56:56,229 the Curiosity rover can do we'd be in a 1497 00:57:01,459 --> 00:56:58,269 position to select samples to bring back 1498 00:57:03,930 --> 00:57:01,469 to earth so now we have this wonderful 1499 00:57:05,939 --> 00:57:03,940 juxtaposition of going to one of the 1500 00:57:08,160 --> 00:57:05,949 most compelling sites on Mars for the 1501 00:57:10,109 --> 00:57:08,170 potential for life and bringing samples 1502 00:57:11,640 --> 00:57:10,119 back to the most capable 1503 00:57:12,930 --> 00:57:11,650 state-of-the-art instruments in 1504 00:57:14,160 --> 00:57:12,940 existence which of course are the 1505 00:57:16,229 --> 00:57:14,170 instruments that we have on the earth 1506 00:57:17,729 --> 00:57:16,239 and this is the great promise that we 1507 00:57:20,130 --> 00:57:17,739 look forward to with the Mars sample 1508 00:57:21,930 --> 00:57:20,140 return mission and we look forward to 1509 00:57:24,410 --> 00:57:21,940 the Mars Science Laboratory mission to 1510 00:57:28,170 --> 00:57:24,420 make additional compelling arguments 1511 00:57:30,089 --> 00:57:28,180 observations to bring closer to the in 1512 00:57:32,099 --> 00:57:30,099 the future the the day we can do the 1513 00:57:34,650 --> 00:57:32,109 sample return mission and with that 1514 00:57:36,959 --> 00:57:34,660 that's our summary of Mars exploration 1515 00:57:38,789 --> 00:57:36,969 and the discoveries we've made and the