1 00:00:01,200 --> 00:00:04,900 [musical tones] [electronic sounds of data] 2 00:00:16,466 --> 00:00:18,000 - Thank you. Thank you. Well, welcome. 3 00:00:18,000 --> 00:00:19,500 What a great turnout. 4 00:00:19,500 --> 00:00:23,566 And welcome to the 2015 NASA Ames Summer Series. 5 00:00:23,566 --> 00:00:26,200 And I have the great honor and pleasure 6 00:00:26,200 --> 00:00:29,466 of introducing one of our two distinguished guests. 7 00:00:29,466 --> 00:00:32,033 I'd like to introduce Dr. Jim Green, 8 00:00:32,033 --> 00:00:35,733 who is our director of planetary sciences for NASA, 9 00:00:35,733 --> 00:00:38,666 and he will do the introduction of our guest speaker. 10 00:00:38,666 --> 00:00:40,000 Welcome again. 11 00:00:40,000 --> 00:00:43,000 [applause] 12 00:00:45,200 --> 00:00:47,100 - Thank you very much, Eugene. 13 00:00:47,100 --> 00:00:51,500 You know, science fiction stories allow us to dream big 14 00:00:51,500 --> 00:00:53,733 and imagine the impossible. 15 00:00:53,733 --> 00:00:56,766 These stories become, in many cases-- 16 00:00:56,766 --> 00:01:00,833 that are classic stories-- become embedded in our minds 17 00:01:00,833 --> 00:01:04,500 and the way we think and the way we work in the future 18 00:01:04,500 --> 00:01:07,166 and in our society. 19 00:01:07,166 --> 00:01:10,700 The stories sometimes allow us to be creative 20 00:01:10,700 --> 00:01:13,133 and invent a new future. 21 00:01:13,133 --> 00:01:16,666 Science fiction is a critical element 22 00:01:16,666 --> 00:01:20,100 of the way we think and the way we act. 23 00:01:20,100 --> 00:01:22,066 Today's colloquium, 24 00:01:22,066 --> 00:01:26,066 "'The Martian': How Science Drove the Plot," 25 00:01:26,066 --> 00:01:29,100 will be presented by Andy Weir. 26 00:01:29,100 --> 00:01:31,333 You know, Andy was hired as a programmer 27 00:01:31,333 --> 00:01:34,733 for a national laboratory at the age of 15 28 00:01:34,733 --> 00:01:38,766 and had been working as a software engineer ever since. 29 00:01:38,766 --> 00:01:42,900 He is also a lifelong space nerd 30 00:01:42,900 --> 00:01:44,566 like many of us 31 00:01:44,566 --> 00:01:46,733 and is a devoted hobbyist 32 00:01:46,733 --> 00:01:49,233 on subjects such as relativistic physics, 33 00:01:49,233 --> 00:01:50,800 orbital mechanics, 34 00:01:50,800 --> 00:01:53,800 and the history of manned space flight. 35 00:01:53,800 --> 00:01:58,166 "The Martian" is Andy's first published novel. 36 00:01:58,166 --> 00:02:01,966 He originally self-published it in 2011 37 00:02:01,966 --> 00:02:05,500 and rereleased it in 2014. 38 00:02:05,500 --> 00:02:08,133 Now, as many know, it's actually been picked up 39 00:02:08,133 --> 00:02:12,700 by 20th Century Fox as a movie. 40 00:02:12,700 --> 00:02:15,166 Ridley Scott is the producer. 41 00:02:15,166 --> 00:02:19,766 If you've seen the trailers, that is a movie I want to see. 42 00:02:19,766 --> 00:02:21,833 But of course I want to tell you, 43 00:02:21,833 --> 00:02:25,866 "The Martian" should be required reading for NASA. 44 00:02:25,866 --> 00:02:29,500 Today Andy will describe how science drove the plot, 45 00:02:29,500 --> 00:02:31,300 illuminating the connectivity 46 00:02:31,300 --> 00:02:34,400 between science fiction and science fact. 47 00:02:34,400 --> 00:02:37,466 So let's give a round of applause to Andy Weir. 48 00:02:37,466 --> 00:02:40,400 [applause] 49 00:02:40,400 --> 00:02:43,066 - Thank you. 50 00:02:43,066 --> 00:02:45,566 All right. 51 00:02:45,566 --> 00:02:47,233 Thank you. 52 00:02:47,233 --> 00:02:49,066 All right. 53 00:02:49,066 --> 00:02:50,466 Hello, everybody. 54 00:02:50,466 --> 00:02:53,433 Um, let me just find out if my wandering mic is hot. 55 00:02:53,433 --> 00:02:54,433 Test, test. 56 00:02:54,433 --> 00:02:56,566 Oh, hey, there we go. 57 00:02:56,566 --> 00:03:00,066 Now I can pontificate from anywhere. 58 00:03:00,066 --> 00:03:02,266 So I'm going to start with a reading, 59 00:03:02,266 --> 00:03:05,733 and then I'm going to talk about how science drove the plot, 60 00:03:05,733 --> 00:03:07,666 as promised. 61 00:03:07,666 --> 00:03:11,133 All right, so there's a lot of profanity in this book, 62 00:03:11,133 --> 00:03:14,366 but a show of hands, who's read it? 63 00:03:14,366 --> 00:03:16,466 Yeah, that's what I like to see. 64 00:03:16,466 --> 00:03:19,100 Show of hands, who's buying it today? 65 00:03:19,100 --> 00:03:21,400 Aw, see, now... 66 00:03:21,400 --> 00:03:24,366 [laughter] 67 00:03:24,366 --> 00:03:26,066 No. 68 00:03:26,066 --> 00:03:30,066 So I'm going to be substituting 69 00:03:30,066 --> 00:03:33,133 softer swear words 70 00:03:33,133 --> 00:03:34,900 for the profanities, 71 00:03:34,900 --> 00:03:38,266 so here we go. 72 00:03:38,266 --> 00:03:40,433 "Log entry: Sol 6. 73 00:03:40,433 --> 00:03:42,666 I'm pretty much 'screwed.' 74 00:03:42,666 --> 00:03:45,366 [laughter] 75 00:03:45,366 --> 00:03:48,500 That's my considered opinion-- screwed. 76 00:03:48,500 --> 00:03:51,766 Six days into what should be the greatest two months of my life 77 00:03:51,766 --> 00:03:53,800 and it's turned into a nightmare. 78 00:03:53,800 --> 00:03:55,366 I don't even know who'll read this. 79 00:03:55,366 --> 00:03:57,566 I guess someone will find it eventually, 80 00:03:57,566 --> 00:03:59,433 maybe 100 years from now. 81 00:03:59,433 --> 00:04:02,366 For the record, I didn't die on Sol 6. 82 00:04:02,366 --> 00:04:04,333 Certainly the rest of the crew thought I did, 83 00:04:04,333 --> 00:04:06,000 and I can't blame them. 84 00:04:06,000 --> 00:04:08,133 Maybe there'll be a day of national mourning for me, 85 00:04:08,133 --> 00:04:09,733 and my Wikipedia page will say, 86 00:04:09,733 --> 00:04:13,066 'Mark Watney is the only human being to have died on Mars.' 87 00:04:13,066 --> 00:04:16,466 And it'll be right, probably, 'cause I'll surely die here, 88 00:04:16,466 --> 00:04:19,733 just not on Sol 6 when everyone thinks I did. 89 00:04:19,733 --> 00:04:21,933 Let's see, where do I begin? 90 00:04:21,933 --> 00:04:23,500 The Ares Program-- 91 00:04:23,500 --> 00:04:26,666 mankind reaching out to Mars to send people to another planet 92 00:04:26,666 --> 00:04:29,866 for the very first time and expand the horizons of humanity, 93 00:04:29,866 --> 00:04:31,833 blah, blah, blah. 94 00:04:31,833 --> 00:04:34,733 The Ares 1 crew did their thing and came back heroes. 95 00:04:34,733 --> 00:04:37,933 They got the parades and fame and love of the world. 96 00:04:37,933 --> 00:04:41,500 Ares 2 did the same thing in a different location on Mars. 97 00:04:41,500 --> 00:04:43,600 They got a firm handshake and a hot cup of coffee 98 00:04:43,600 --> 00:04:45,233 when they got home. 99 00:04:45,233 --> 00:04:48,100 Ares 3, well, that was my mission. 100 00:04:48,100 --> 00:04:50,400 Okay, not mine, per se. 101 00:04:50,400 --> 00:04:52,100 Commander Lewis was in charge. 102 00:04:52,100 --> 00:04:54,200 I was just one of her crew. 103 00:04:54,200 --> 00:04:56,100 Actually, I was the very lowest-ranked member 104 00:04:56,100 --> 00:04:57,500 of her crew. 105 00:04:57,500 --> 00:04:59,366 I would only be 'in command' of the mission 106 00:04:59,366 --> 00:05:01,233 if I were the only remaining person. 107 00:05:01,233 --> 00:05:02,700 Hey, what do you know? I'm in command. 108 00:05:02,700 --> 00:05:05,466 [laughter] 109 00:05:05,466 --> 00:05:07,166 I wonder if this log will be recovered 110 00:05:07,166 --> 00:05:09,733 before the rest of the crew die of old age. 111 00:05:09,733 --> 00:05:12,100 I presume they got back to Earth all right. 112 00:05:12,100 --> 00:05:14,866 Guys, if you're reading this, it wasn't your fault. 113 00:05:14,866 --> 00:05:16,200 You did what you had to do. 114 00:05:16,200 --> 00:05:18,933 In your position, I would have done the same thing. 115 00:05:18,933 --> 00:05:21,666 I don't blame you, and I'm glad you survived. 116 00:05:21,666 --> 00:05:24,366 I guess I should explain how Mars missions work 117 00:05:24,366 --> 00:05:26,966 for any layman who may be reading this. 118 00:05:26,966 --> 00:05:29,000 We got to Earth orbit the normal way, 119 00:05:29,000 --> 00:05:30,966 through an ordinary ship to Hermes. 120 00:05:30,966 --> 00:05:32,733 All the area's missions use Hermes 121 00:05:32,733 --> 00:05:34,300 to get to and from Mars. 122 00:05:34,300 --> 00:05:36,400 It's really big, and it cost a lot, 123 00:05:36,400 --> 00:05:38,033 so NASA only built one. 124 00:05:38,033 --> 00:05:42,166 Once we got to Hermes, four additional unmanned missions 125 00:05:42,166 --> 00:05:45,966 brought us fuel and supplies while we prepared for our trip. 126 00:05:45,966 --> 00:05:48,566 Once everything was a go, we set out for Mars, 127 00:05:48,566 --> 00:05:50,133 but not very fast. 128 00:05:50,133 --> 00:05:52,366 Gone are the days of heavy chemical fuel burns 129 00:05:52,366 --> 00:05:54,700 and trans-Mars injection orbits. 130 00:05:54,700 --> 00:05:57,700 Hermes is powered by ion engines. 131 00:05:57,700 --> 00:06:00,300 They throw argon out the back of the ship really fast 132 00:06:00,300 --> 00:06:02,566 to get a tiny amount of acceleration. 133 00:06:02,566 --> 00:06:05,733 The thing is, it doesn't take much reactant mass, 134 00:06:05,733 --> 00:06:08,500 so a little argon and a nuclear reactor to power things 135 00:06:08,500 --> 00:06:11,466 let us accelerate constantly the whole way there. 136 00:06:11,466 --> 00:06:13,433 You'd be amazed at how fast you can get going 137 00:06:13,433 --> 00:06:16,566 with a tiny acceleration over a long time. 138 00:06:16,566 --> 00:06:18,400 I could regale you with tales 139 00:06:18,400 --> 00:06:21,266 of how we had great fun on the trip, but I won't. 140 00:06:21,266 --> 00:06:23,300 I don't feel like reliving it right now. 141 00:06:23,300 --> 00:06:26,333 Suffice it to say, we got to Mars 124 days later 142 00:06:26,333 --> 00:06:28,766 without strangling each other. 143 00:06:28,766 --> 00:06:32,200 From there, we took the MDV, Mars Descent Vehicle, 144 00:06:32,200 --> 00:06:33,866 to the surface. 145 00:06:33,866 --> 00:06:35,800 The MDV is basically a big can 146 00:06:35,800 --> 00:06:38,666 with some light thrusters and parachutes attached. 147 00:06:38,666 --> 00:06:41,633 Its sole purpose is to get six humans from Mars' orbit 148 00:06:41,633 --> 00:06:44,500 to the surface without killing any of them. 149 00:06:44,500 --> 00:06:47,200 And now we get to the real trick of Mars exploration-- 150 00:06:47,200 --> 00:06:50,533 having all your crap there in advance. 151 00:06:50,533 --> 00:06:52,633 A total of 14 unmanned missions 152 00:06:52,633 --> 00:06:55,900 deposited everything we would need for surface operations. 153 00:06:55,900 --> 00:06:58,033 They tried their best to land all the supply vessels 154 00:06:58,033 --> 00:07:01,766 in the same general area and did a reasonably good job. 155 00:07:01,766 --> 00:07:03,933 Supplies aren't nearly so fragile as humans 156 00:07:03,933 --> 00:07:05,866 and can hit the ground really hard, 157 00:07:05,866 --> 00:07:08,833 but they tend to bounce around a lot. 158 00:07:08,833 --> 00:07:10,533 Naturally, they didn't send us to Mars 159 00:07:10,533 --> 00:07:12,733 until they'd confirmed that all the supplies had made it 160 00:07:12,733 --> 00:07:15,333 to the surface and their containers weren't breached. 161 00:07:15,333 --> 00:07:17,800 Start to finish, including supply missions, 162 00:07:17,800 --> 00:07:20,366 a Mars mission takes about three years. 163 00:07:20,366 --> 00:07:23,333 In fact, there were Ares 3 supplies en route to Mars 164 00:07:23,333 --> 00:07:26,866 while the Ares 2 crew were on their way home. 165 00:07:26,866 --> 00:07:29,800 The most important piece of advance supplies, of course, 166 00:07:29,800 --> 00:07:32,666 was the MAV-- the Mars Ascent Vehicle. 167 00:07:32,666 --> 00:07:34,133 That's how we would get back to Hermes 168 00:07:34,133 --> 00:07:36,500 after surface operations were complete. 169 00:07:36,500 --> 00:07:38,233 The MAV was soft-landed, 170 00:07:38,233 --> 00:07:40,066 as opposed to the balloon bounce-fest 171 00:07:40,066 --> 00:07:42,033 the other supplies had. 172 00:07:42,033 --> 00:07:44,900 Of course, it was in constant communication with Houston, 173 00:07:44,900 --> 00:07:47,066 and if there had been any problems with it, 174 00:07:47,066 --> 00:07:50,300 we would have passed by Mars and gone home without ever landing. 175 00:07:50,300 --> 00:07:52,000 The MAV is pretty cool. 176 00:07:52,000 --> 00:07:54,100 Turns out, through a neat set of chemical reactions 177 00:07:54,100 --> 00:07:55,733 with the Martian atmosphere, 178 00:07:55,733 --> 00:07:58,133 for every kilogram of hydrogen you bring to Mars, 179 00:07:58,133 --> 00:08:00,566 you can make 13 kilograms of fuel. 180 00:08:00,566 --> 00:08:02,300 It's a slow process, though. 181 00:08:02,300 --> 00:08:04,533 It takes 24 months to fill the tank. 182 00:08:04,533 --> 00:08:06,900 That's why they sent it long before we got here. 183 00:08:06,900 --> 00:08:08,700 You can imagine how disappointed I was 184 00:08:08,700 --> 00:08:12,033 when I discovered the MAV was gone. 185 00:08:12,033 --> 00:08:14,066 It was a ridiculous sequence of events 186 00:08:14,066 --> 00:08:15,533 that led to me almost dying 187 00:08:15,533 --> 00:08:17,000 and an even more ridiculous sequence 188 00:08:17,000 --> 00:08:18,633 that led to me surviving. 189 00:08:18,633 --> 00:08:20,900 The mission is designed to handle sandstorm gusts 190 00:08:20,900 --> 00:08:23,700 up to 150 kilometers per hour. 191 00:08:23,700 --> 00:08:26,400 So Houston got understandably nervous when we got whacked 192 00:08:26,400 --> 00:08:29,000 with 175-kilometer-per-hour winds. 193 00:08:29,000 --> 00:08:30,633 We all got in our flight space suits 194 00:08:30,633 --> 00:08:32,166 and huddled in the middle of the Hab 195 00:08:32,166 --> 00:08:35,700 just in case it lost pressure, but the Hab wasn't the problem. 196 00:08:35,700 --> 00:08:37,333 The MAV is a spaceship. 197 00:08:37,333 --> 00:08:39,300 It has a lot of delicate parts. 198 00:08:39,300 --> 00:08:41,533 It can put up with storms to a certain extent, 199 00:08:41,533 --> 00:08:43,966 but it can't just get sandblasted forever. 200 00:08:43,966 --> 00:08:46,400 After an hour and a half of sustained wind, 201 00:08:46,400 --> 00:08:48,066 NASA gave the order to abort. 202 00:08:48,066 --> 00:08:50,000 Nobody wanted to stop a month-long mission 203 00:08:50,000 --> 00:08:51,400 after only six days, 204 00:08:51,400 --> 00:08:53,166 but if the MAV took anymore punishment, 205 00:08:53,166 --> 00:08:56,166 we'd all have gotten stranded down there. 206 00:08:56,166 --> 00:08:59,666 We had to go out into the storm to get from the Hab to the MAV. 207 00:08:59,666 --> 00:09:02,400 That was going to be risky, but what choice did we have? 208 00:09:02,400 --> 00:09:04,933 Everyone made it but me. 209 00:09:04,933 --> 00:09:06,700 Our main communications dish, 210 00:09:06,700 --> 00:09:09,200 which relayed signals from the Hab to Hermes, 211 00:09:09,200 --> 00:09:11,966 acted like a parachute, getting torn from its foundation 212 00:09:11,966 --> 00:09:13,800 and carried along with the torrent. 213 00:09:13,800 --> 00:09:15,066 Along the way, 214 00:09:15,066 --> 00:09:17,266 it crashed through the reception antenna array. 215 00:09:17,266 --> 00:09:18,733 Then one of those long, thin antennae 216 00:09:18,733 --> 00:09:20,800 slammed into me end-first. 217 00:09:20,800 --> 00:09:23,266 It tore through my suit like a bullet through butter, 218 00:09:23,266 --> 00:09:26,866 and I felt the worst pain in my life as it ripped open my side. 219 00:09:26,866 --> 00:09:29,100 I vaguely remember having the wind knocked out of me, 220 00:09:29,100 --> 00:09:30,533 pulled out of me really, 221 00:09:30,533 --> 00:09:34,066 and my ears popping painfully as the pressure of my suit escaped. 222 00:09:34,066 --> 00:09:35,333 The last thing I remember 223 00:09:35,333 --> 00:09:39,066 was seeing Johanssen hopelessly reaching out toward me. 224 00:09:39,066 --> 00:09:41,366 I awoke to the oxygen alarm in my suit-- 225 00:09:41,366 --> 00:09:44,200 a steady, obnoxious beeping that eventually roused me 226 00:09:44,200 --> 00:09:47,700 from a deep and profound desire to just die. 227 00:09:47,700 --> 00:09:49,166 The storm had abated. 228 00:09:49,166 --> 00:09:51,933 I was facedown, almost totally buried in sand. 229 00:09:51,933 --> 00:09:53,400 As I groggily came to, 230 00:09:53,400 --> 00:09:56,133 I wondered why I wasn't more dead. 231 00:09:56,133 --> 00:09:57,566 The antenna had enough force 232 00:09:57,566 --> 00:09:59,566 to punch through the suit and my side, 233 00:09:59,566 --> 00:10:01,500 but it had been stopped by my pelvis, 234 00:10:01,500 --> 00:10:03,233 so there was only one hole in the suit 235 00:10:03,233 --> 00:10:05,400 and a hole in me, of course. 236 00:10:05,400 --> 00:10:07,100 I'd been knocked back quite a ways 237 00:10:07,100 --> 00:10:08,900 and rolled down a steep hill. 238 00:10:08,900 --> 00:10:10,600 Somehow, I landed facedown, 239 00:10:10,600 --> 00:10:13,033 which forced the antenna to a strongly oblique angle 240 00:10:13,033 --> 00:10:15,766 that put a lot of torque on the hole in my suit. 241 00:10:15,766 --> 00:10:17,633 It made a weak seal. 242 00:10:17,633 --> 00:10:20,066 Then the copious blood from my wound 243 00:10:20,066 --> 00:10:21,900 trickled down toward the hole. 244 00:10:21,900 --> 00:10:23,900 As the blood reached the site of the breach, 245 00:10:23,900 --> 00:10:25,400 the water in it quickly evaporated 246 00:10:25,400 --> 00:10:27,066 from airflow and low pressure, 247 00:10:27,066 --> 00:10:29,266 leaving a gunky residue behind. 248 00:10:29,266 --> 00:10:32,333 More blood came in behind it and was also reduced to gunk. 249 00:10:32,333 --> 00:10:34,733 Eventually, it sealed the gaps around the hole 250 00:10:34,733 --> 00:10:35,900 and reduced the leak 251 00:10:35,900 --> 00:10:38,800 to something the suit could counteract. 252 00:10:38,800 --> 00:10:40,933 The suit did its job admirably. 253 00:10:40,933 --> 00:10:43,800 Sensing the drop in pressure, it constantly flooded itself 254 00:10:43,800 --> 00:10:46,600 with air from my nitrogen tank to equalize. 255 00:10:46,600 --> 00:10:48,266 Once the leak became manageable, 256 00:10:48,266 --> 00:10:50,000 it only had to trickle new air in slowly 257 00:10:50,000 --> 00:10:51,733 to relieve the air lost. 258 00:10:51,733 --> 00:10:53,000 After a while, 259 00:10:53,000 --> 00:10:55,966 the CO2--carbon dioxide-- absorbers in the suit 260 00:10:55,966 --> 00:10:57,366 were expended. 261 00:10:57,366 --> 00:10:59,766 That's really the limiting factor to life support-- 262 00:10:59,766 --> 00:11:02,000 not the amount of oxygen you can bring with you, 263 00:11:02,000 --> 00:11:04,200 but the amount of CO2 you can remove. 264 00:11:04,200 --> 00:11:06,500 In the Hab, I had the oxygenator-- 265 00:11:06,500 --> 00:11:09,066 a large piece of equipment that breaks CO2 apart 266 00:11:09,066 --> 00:11:10,733 to give the oxygen back, 267 00:11:10,733 --> 00:11:13,333 but in the space suits, they have to be portable, 268 00:11:13,333 --> 00:11:15,466 so they use a simple chemical-absorption process 269 00:11:15,466 --> 00:11:17,100 with expendable filters. 270 00:11:17,100 --> 00:11:21,066 I'd been asleep long enough that my filters were useless. 271 00:11:21,066 --> 00:11:23,766 The suit saw this problem and moved into an emergency mode 272 00:11:23,766 --> 00:11:25,933 the engineers called 'bloodletting.' 273 00:11:25,933 --> 00:11:28,266 Having no way to separate out the CO2, 274 00:11:28,266 --> 00:11:31,100 the suit deliberately vented air to the Martian atmosphere, 275 00:11:31,100 --> 00:11:32,800 then backfilled with nitrogen. 276 00:11:32,800 --> 00:11:34,466 Between the breach and the bloodletting, 277 00:11:34,466 --> 00:11:36,433 it quickly ran out of nitrogen. 278 00:11:36,433 --> 00:11:38,833 All it had left was my oxygen tank. 279 00:11:38,833 --> 00:11:41,366 So it did the only thing it could to keep me alive-- 280 00:11:41,366 --> 00:11:44,033 it started backfilling with pure oxygen. 281 00:11:44,033 --> 00:11:46,200 I now risked dying from oxygen toxicity, 282 00:11:46,200 --> 00:11:49,066 as the excessively high amount of oxygen threatened to burn up 283 00:11:49,066 --> 00:11:51,100 my nervous system, lungs, and eyes. 284 00:11:51,100 --> 00:11:53,800 An ironic death for someone with a leaky space suit-- 285 00:11:53,800 --> 00:11:55,800 too much oxygen. 286 00:11:55,800 --> 00:11:57,133 Every step of the way 287 00:11:57,133 --> 00:11:59,166 would have had beeping alarms, alerts, and warnings, 288 00:11:59,166 --> 00:12:00,900 but it was the high-oxygen warning 289 00:12:00,900 --> 00:12:02,833 that eventually woke me. 290 00:12:02,833 --> 00:12:06,166 The sheer volume of training for a space mission is astounding. 291 00:12:06,166 --> 00:12:07,266 I'd spent a week back on Earth 292 00:12:07,266 --> 00:12:09,733 practicing emergency space suit drills. 293 00:12:09,733 --> 00:12:11,066 I knew what to do. 294 00:12:11,066 --> 00:12:12,833 Carefully reaching to the side of my helmet, 295 00:12:12,833 --> 00:12:14,366 I got the breach kit. 296 00:12:14,366 --> 00:12:17,366 It's nothing more than a funnel with a valve at the small end 297 00:12:17,366 --> 00:12:20,166 and an unbelievably sticky resin on the wide end. 298 00:12:20,166 --> 00:12:21,800 The idea is, you have the valve open 299 00:12:21,800 --> 00:12:24,000 and stick the wide end over a hole. 300 00:12:24,000 --> 00:12:25,566 The air can escape through the valve 301 00:12:25,566 --> 00:12:28,400 so it doesn't interfere with the resin, making a good seal. 302 00:12:28,400 --> 00:12:31,200 Then you close the valve, and you've sealed the breach. 303 00:12:31,200 --> 00:12:34,166 The tricky part was getting the antenna out of the way. 304 00:12:34,166 --> 00:12:35,766 I pulled it out as fast as I could, 305 00:12:35,766 --> 00:12:37,866 wincing as the sudden pressure drop dizzied me 306 00:12:37,866 --> 00:12:40,833 and made the wound in my side scream in agony. 307 00:12:40,833 --> 00:12:43,266 I got the breach kit over the hole and sealed it. 308 00:12:43,266 --> 00:12:44,766 It held. 309 00:12:44,766 --> 00:12:48,133 The suit backfilled the missing air with yet more oxygen. 310 00:12:48,133 --> 00:12:49,566 Checking my arm readouts, 311 00:12:49,566 --> 00:12:52,366 I saw the suit was now 85% oxygen. 312 00:12:52,366 --> 00:12:55,633 For reference, Earth's atmosphere is about 21%. 313 00:12:55,633 --> 00:12:59,900 I'd be okay, so long as I didn't spend too much time like that. 314 00:12:59,900 --> 00:13:02,466 I stumbled up the hill and back toward the Hab. 315 00:13:02,466 --> 00:13:03,600 As I crested the rise, 316 00:13:03,600 --> 00:13:05,166 I saw something that made me very happy 317 00:13:05,166 --> 00:13:07,000 and something that made me very sad. 318 00:13:07,000 --> 00:13:09,100 The Hab was intact. Yay! 319 00:13:09,100 --> 00:13:12,533 And the MAV was gone. Boo! 320 00:13:12,533 --> 00:13:14,800 Right at that moment, I knew I was screwed, 321 00:13:14,800 --> 00:13:17,233 but I didn't want to just die out on the surface. 322 00:13:17,233 --> 00:13:20,300 I limped back to the Hab and fumbled my way into an airlock. 323 00:13:20,300 --> 00:13:23,033 As soon as it equalized, I threw off my helmet. 324 00:13:23,033 --> 00:13:24,500 Once inside the Hab, 325 00:13:24,500 --> 00:13:27,333 I doffed the suit and got my first good look at the injury. 326 00:13:27,333 --> 00:13:28,933 It would need stitches. 327 00:13:28,933 --> 00:13:30,500 Fortunately, all of us had been trained 328 00:13:30,500 --> 00:13:32,166 in basic medical procedures, 329 00:13:32,166 --> 00:13:34,400 and the Hab had excellent medical supplies. 330 00:13:34,400 --> 00:13:36,233 A quick shot of local anesthetic, 331 00:13:36,233 --> 00:13:39,266 irrigate the wound, nine stitches, and I was done. 332 00:13:39,266 --> 00:13:41,333 I'd be taking antibiotics for a couple of weeks, 333 00:13:41,333 --> 00:13:43,866 but other than that, I'd be fine. 334 00:13:43,866 --> 00:13:45,166 I knew it was hopeless, 335 00:13:45,166 --> 00:13:47,433 but I tried firing up the communications array. 336 00:13:47,433 --> 00:13:48,933 No signal, of course. 337 00:13:48,933 --> 00:13:51,400 The primary satellite dish had broken off, remember? 338 00:13:51,400 --> 00:13:54,500 And it took the reception array with it. 339 00:13:54,500 --> 00:13:57,533 The Hab had secondary and tertiary communication systems, 340 00:13:57,533 --> 00:13:59,800 but they were both just for talking to the MAV, 341 00:13:59,800 --> 00:14:01,700 which would use its much more powerful systems 342 00:14:01,700 --> 00:14:03,066 to relay to Hermes. 343 00:14:03,066 --> 00:14:06,866 Thing is, that only works if the MAV is still around. 344 00:14:06,866 --> 00:14:08,900 I had no way to talk to Hermes. 345 00:14:08,900 --> 00:14:11,400 In time, I could locate the dish out on the surface, 346 00:14:11,400 --> 00:14:13,933 but it would take weeks for me to rig up any repairs, 347 00:14:13,933 --> 00:14:15,833 and by then, it would be too late. 348 00:14:15,833 --> 00:14:17,566 In an abort, Hermes would leave orbit 349 00:14:17,566 --> 00:14:18,900 within 24 hours. 350 00:14:18,900 --> 00:14:21,166 The orbital dynamics made the trip safer and shorter 351 00:14:21,166 --> 00:14:23,900 the earlier you left, so why wait? 352 00:14:23,900 --> 00:14:25,400 Checking out my suit, 353 00:14:25,400 --> 00:14:28,333 I saw the antenna had plowed through my bio-monitor computer. 354 00:14:28,333 --> 00:14:31,133 When on an EVA, all the crew's suits are networked 355 00:14:31,133 --> 00:14:33,066 so that we can see each other's status. 356 00:14:33,066 --> 00:14:34,466 The rest of the crew 357 00:14:34,466 --> 00:14:36,900 would have seen the pressure in my suit drop to nearly zero, 358 00:14:36,900 --> 00:14:40,200 followed immediately by my bio-signs going flat. 359 00:14:40,200 --> 00:14:41,933 Add to that watching me tumble down a hill 360 00:14:41,933 --> 00:14:44,466 with a spear through me in the middle of a sandstorm, 361 00:14:44,466 --> 00:14:46,133 yeah, they thought I was dead. 362 00:14:46,133 --> 00:14:47,633 How could they not? 363 00:14:47,633 --> 00:14:49,233 They may have even had a brief discussion 364 00:14:49,233 --> 00:14:50,800 about recovering my body. 365 00:14:50,800 --> 00:14:52,333 But regulations are clear. 366 00:14:52,333 --> 00:14:55,333 In the event a crewman dies on Mars, he stays on Mars. 367 00:14:55,333 --> 00:14:57,733 Leaving his body behind reduces weight for the MAV 368 00:14:57,733 --> 00:14:59,133 on the trip back. 369 00:14:59,133 --> 00:15:01,633 That means more disposable fuel and a larger margin of error 370 00:15:01,633 --> 00:15:03,233 for the return thrust. 371 00:15:03,233 --> 00:15:05,866 No point in giving that up for sentimentality. 372 00:15:05,866 --> 00:15:07,333 So that's the situation. 373 00:15:07,333 --> 00:15:08,800 I'm stranded on Mars. 374 00:15:08,800 --> 00:15:11,266 I have no way to communicate with Hermes or Earth. 375 00:15:11,266 --> 00:15:12,866 Everyone thinks I'm dead. 376 00:15:12,866 --> 00:15:15,500 I'm in a Hab designed to last 31 days. 377 00:15:15,500 --> 00:15:18,366 If the oxygenator breaks down, I'll suffocate. 378 00:15:18,366 --> 00:15:21,166 If the water reclaimer breaks down, I'll die of thirst. 379 00:15:21,166 --> 00:15:24,033 If the Hab breaches, I'll just kind of explode. 380 00:15:24,033 --> 00:15:25,533 If none of those things happen, 381 00:15:25,533 --> 00:15:27,600 I'll eventually run out of food and starve to death. 382 00:15:27,600 --> 00:15:29,133 So, yeah, I'm screwed." 383 00:15:29,133 --> 00:15:31,233 [laughter] 384 00:15:31,233 --> 00:15:32,433 Thank you. 385 00:15:32,433 --> 00:15:35,433 [applause] 386 00:15:40,166 --> 00:15:43,000 So I put a lot of work into trying to make 387 00:15:43,000 --> 00:15:45,400 the science as accurate as possible in this book, 388 00:15:45,400 --> 00:15:47,133 because at the time that I wrote it, 389 00:15:47,133 --> 00:15:49,666 I was writing it for a small core group of nerdy readers 390 00:15:49,666 --> 00:15:51,833 who were on my mailing list, 391 00:15:51,833 --> 00:15:54,233 'cause, initially, I wrote it just-- 392 00:15:54,233 --> 00:15:57,500 I published it a chapter at a time to my website. 393 00:15:57,500 --> 00:16:00,900 And I had about 3,000 regular readers, 394 00:16:00,900 --> 00:16:03,733 and that was it. 395 00:16:03,733 --> 00:16:06,933 But they were all, like, hard-core science-y people, 396 00:16:06,933 --> 00:16:09,633 because that's the sort of stuff that I wrote. 397 00:16:09,633 --> 00:16:12,733 So, I realized that I had to be accurate on the science, 398 00:16:12,733 --> 00:16:14,466 or as accurate as I could be. 399 00:16:14,466 --> 00:16:18,366 And, so that's why I put so much effort into scientific accuracy. 400 00:16:18,366 --> 00:16:20,233 I had no notion or concept 401 00:16:20,233 --> 00:16:22,133 that the book would have any mainstream appeal. 402 00:16:22,133 --> 00:16:24,433 I thought it would just be for dorks and geeks and dweebs 403 00:16:24,433 --> 00:16:26,000 and, you know, you. 404 00:16:26,000 --> 00:16:27,400 [laughter] 405 00:16:27,400 --> 00:16:28,566 So, um-- 406 00:16:28,566 --> 00:16:31,466 And me, you know. 407 00:16:31,466 --> 00:16:34,500 So I was really surprised to see that it took off so well. 408 00:16:34,500 --> 00:16:36,633 And what I'm going to talk to you about today 409 00:16:36,633 --> 00:16:38,566 is how science drove the plot. 410 00:16:38,566 --> 00:16:39,900 A lot of people ask me-- 411 00:16:39,900 --> 00:16:42,133 So the book has very simple formula-- 412 00:16:42,133 --> 00:16:44,900 problem, solution, problem, solution, problem, solution. 413 00:16:44,900 --> 00:16:46,900 And a question I get asked a lot is, 414 00:16:46,900 --> 00:16:48,400 "Did you come up with the problems first, 415 00:16:48,400 --> 00:16:50,166 or did you come up with the solutions first 416 00:16:50,166 --> 00:16:52,100 and then work out a problem?" 417 00:16:52,100 --> 00:16:54,400 And the answer is, I came up with the problems first. 418 00:16:54,400 --> 00:16:57,100 I tried to have each problem be caused 419 00:16:57,100 --> 00:16:59,400 by the solution to the previous problem. 420 00:16:59,400 --> 00:17:00,666 Like, "Oh, this broke, 421 00:17:00,666 --> 00:17:02,500 so I took apart this other thing to fix that. 422 00:17:02,500 --> 00:17:04,233 Oh, well, now the other thing doesn't work," 423 00:17:04,233 --> 00:17:05,533 and so on. 424 00:17:05,533 --> 00:17:09,266 And so the whole plot is driven by the realities 425 00:17:09,266 --> 00:17:12,166 of the physical world that we live in 426 00:17:12,166 --> 00:17:14,733 or the one he lives on, anyway. 427 00:17:17,066 --> 00:17:19,700 It was interesting, because just by sitting down 428 00:17:19,700 --> 00:17:21,800 and doing the math on these things, 429 00:17:21,800 --> 00:17:24,600 just making no pleasant assumptions 430 00:17:24,600 --> 00:17:26,666 and just doing the math on everything, 431 00:17:26,666 --> 00:17:29,733 I kept finding more and more problems. 432 00:17:29,733 --> 00:17:31,933 And that's good because that's what I wanted. 433 00:17:31,933 --> 00:17:34,566 So one example is early on. 434 00:17:34,566 --> 00:17:37,733 Very early in the book, he realizes-- 435 00:17:37,733 --> 00:17:39,400 Like, in fact, in the part I read, 436 00:17:39,400 --> 00:17:41,466 he realizes he doesn't have enough food, 437 00:17:41,466 --> 00:17:44,600 and he goes about trying to grow his own crops. 438 00:17:44,600 --> 00:17:46,033 He grows potatoes in the Hab 439 00:17:46,033 --> 00:17:48,600 to try to generate enough calories to survive. 440 00:17:48,600 --> 00:17:50,900 And I was like, "Okay, well, he's a botanist, 441 00:17:50,900 --> 00:17:52,733 so let's assume he knows anything 442 00:17:52,733 --> 00:17:54,500 that I can look up," right? 443 00:17:54,500 --> 00:17:55,966 And so I said, 444 00:17:55,966 --> 00:17:58,133 "Okay, well how would you grow potatoes on Mars?" 445 00:17:58,133 --> 00:18:00,466 Well, here's how you grow potatoes, in general, 446 00:18:00,466 --> 00:18:03,933 and assume he's got adequate lighting from internal lights 447 00:18:03,933 --> 00:18:05,300 and stuff like that. 448 00:18:05,300 --> 00:18:06,600 And one thing I found out as well, 449 00:18:06,600 --> 00:18:08,333 it needs a medium to grow in. 450 00:18:08,333 --> 00:18:11,166 So he used just Martian soil that he brought in, 451 00:18:11,166 --> 00:18:13,000 and then I'm like, "Well, wait a minute. 452 00:18:13,000 --> 00:18:14,933 How much water does that soil need?" 453 00:18:14,933 --> 00:18:16,900 'Cause Martian soil's pretty dry. 454 00:18:16,900 --> 00:18:18,066 [laughs] 455 00:18:18,066 --> 00:18:20,066 And it turns out he'd need something 456 00:18:20,066 --> 00:18:23,366 like 600 liters of water to cover the soil 457 00:18:23,366 --> 00:18:26,566 to moisten the soil sufficiently for potatoes to grow. 458 00:18:26,566 --> 00:18:30,466 And I was like, "There is no way they'd bring 600 liters of water 459 00:18:30,466 --> 00:18:33,200 on a manned Mars mission when they have a water reclaimer." 460 00:18:33,200 --> 00:18:34,333 All they need is, like, 461 00:18:34,333 --> 00:18:37,433 you know, some amount of water in reserve 462 00:18:37,433 --> 00:18:39,466 to last them long enough to evacuate 463 00:18:39,466 --> 00:18:40,933 if they lose their water system. 464 00:18:40,933 --> 00:18:44,000 They really don't need to bring 600 liters of water. 465 00:18:44,000 --> 00:18:45,533 That's 600 kilograms. 466 00:18:45,533 --> 00:18:48,066 See, I did the math there in my head. 467 00:18:48,066 --> 00:18:49,766 That's a lot of mass, right? 468 00:18:49,766 --> 00:18:51,133 And so I'm like, 469 00:18:51,133 --> 00:18:54,066 "How the hell is he going to get 600 liters of water?" 470 00:18:54,066 --> 00:18:55,533 And then so I said, like, 471 00:18:55,533 --> 00:18:58,133 "All right, well, that's a problem he's got to solve." 472 00:18:58,133 --> 00:18:59,566 And so it was really cool, because-- 473 00:18:59,566 --> 00:19:01,966 And then there's this whole plotline in the book 474 00:19:01,966 --> 00:19:03,866 where he's manufacturing water. 475 00:19:03,866 --> 00:19:08,000 He's reducing leftover hydrazine from the MDV 476 00:19:08,000 --> 00:19:09,466 to liberate the hydrogen. 477 00:19:09,466 --> 00:19:13,800 He can get oxygen by collecting CO2 from the Martian atmosphere 478 00:19:13,800 --> 00:19:15,566 and then running it through the oxygenator 479 00:19:15,566 --> 00:19:16,833 to liberate the oxygen. 480 00:19:16,833 --> 00:19:18,166 Now he has hydrogen and oxygen, 481 00:19:18,166 --> 00:19:20,166 and he can put them together to make water. 482 00:19:20,166 --> 00:19:22,666 Things don't go as smoothly as he'd like on that process, 483 00:19:22,666 --> 00:19:26,133 especially the "mixing the hydrogen and oxygen" part... 484 00:19:27,766 --> 00:19:29,800 But it's just one of those examples 485 00:19:29,800 --> 00:19:32,266 of where just doing the math and checking the science 486 00:19:32,266 --> 00:19:34,300 had huge effects on the plot. 487 00:19:34,300 --> 00:19:36,400 And that happened over and over again. 488 00:19:36,400 --> 00:19:38,233 What I'm going to show you now is-- 489 00:19:38,233 --> 00:19:39,966 So I'm a software engineer, 490 00:19:39,966 --> 00:19:43,300 and I spent 25 years writing software 491 00:19:43,300 --> 00:19:45,900 before I wrote "The Martian." 492 00:19:45,900 --> 00:19:48,833 When the only tool you have is a hammer, 493 00:19:48,833 --> 00:19:52,166 every problem starts to look like a nail. 494 00:19:52,166 --> 00:19:55,366 And so, when I was trying to figure out the orbital dynamics 495 00:19:55,366 --> 00:19:59,100 of how Hermes got between Earth and Mars, 496 00:19:59,100 --> 00:20:00,400 I was like, 497 00:20:00,400 --> 00:20:03,300 "Well, how do you do this? How do you do this?" 498 00:20:03,300 --> 00:20:05,900 'Cause it's relatively easy in orbital dynamics 499 00:20:05,900 --> 00:20:10,166 to figure out how to get a ship from one point to another-- 500 00:20:10,166 --> 00:20:13,266 an intercept orbit or just a transfer orbit 501 00:20:13,266 --> 00:20:16,100 and then another thrust to match the orbit of your target. 502 00:20:16,100 --> 00:20:18,400 It seems complicated, 503 00:20:18,400 --> 00:20:20,066 but in the grand scheme of things, 504 00:20:20,066 --> 00:20:21,733 it's not that complicated, 505 00:20:21,733 --> 00:20:23,433 at least not for a fiction writer 506 00:20:23,433 --> 00:20:25,900 where I don't need to have the huge levels of accuracy 507 00:20:25,900 --> 00:20:28,500 that a real mission would have, right? 508 00:20:28,500 --> 00:20:30,233 But I had no idea how to deal 509 00:20:30,233 --> 00:20:33,066 with a constantly accelerating craft. 510 00:20:33,066 --> 00:20:35,233 Hermes is powered by ion engines, 511 00:20:35,233 --> 00:20:38,333 which use, basically, a nuclear reactor for power 512 00:20:38,333 --> 00:20:42,200 to rapidly accelerate, in this case, argon atoms, 513 00:20:42,200 --> 00:20:45,800 such that they go so fast, they pick up relativistic mass, 514 00:20:45,800 --> 00:20:49,500 which is why you don't need nearly as much reactant mass. 515 00:20:49,500 --> 00:20:52,000 It has a much better specific impulse 516 00:20:52,000 --> 00:20:55,100 than traditional chemical rocket propellant. 517 00:20:55,100 --> 00:20:57,066 And it's a good way-- Hey, screen saver. 518 00:20:57,066 --> 00:21:01,900 It's a good way to do interplanetary travel. 519 00:21:01,900 --> 00:21:03,400 And I'm like, "How the hell 520 00:21:03,400 --> 00:21:05,233 do I calculate an orbital trajectory 521 00:21:05,233 --> 00:21:07,200 with a constantly accelerating craft?" 522 00:21:07,200 --> 00:21:09,166 And I started trying to do the math on this, 523 00:21:09,166 --> 00:21:11,066 and once I was, like, ten integrals deep, 524 00:21:11,066 --> 00:21:13,633 I realized I was in way over my head. 525 00:21:13,633 --> 00:21:16,433 And I went--I emailed around to mathematicians and stuff, 526 00:21:16,433 --> 00:21:18,366 and they're like, "I don't know. God be with you." 527 00:21:18,366 --> 00:21:20,533 [laughter] 528 00:21:20,533 --> 00:21:23,566 And so I said, like, "Well, what does NASA do?" 529 00:21:23,566 --> 00:21:25,233 I mean, NASA, they worked with-- 530 00:21:25,233 --> 00:21:27,233 By the way, ion engines-- I didn't make this up. 531 00:21:27,233 --> 00:21:28,633 This is a real technology. 532 00:21:28,633 --> 00:21:31,533 Probably most of you know that, but it's a real thing 533 00:21:31,533 --> 00:21:34,066 that has genuinely been used in missions. 534 00:21:34,066 --> 00:21:38,733 Most recently the GRAIL mission used ion propulsion. 535 00:21:38,733 --> 00:21:39,866 [light laughter] 536 00:21:39,866 --> 00:21:41,533 No? They're laughing. 537 00:21:41,533 --> 00:21:43,900 Dawn. Well, Dawn also. Yeah. 538 00:21:43,900 --> 00:21:46,566 [laughs] 539 00:21:46,566 --> 00:21:50,233 The moon-- The ones that mapped the moon. 540 00:21:50,233 --> 00:21:51,400 They didn't? - No. 541 00:21:51,400 --> 00:21:52,733 - Oh, oh, I'm wrong. - Dawn did.