1 00:00:01,000 --> 00:00:07,000 [music playing] 2 00:00:17,433 --> 00:00:19,366 - WELCOME TO THE 75TH ANNIVERSARY 3 00:00:19,366 --> 00:00:21,366 OF NASA AMES RESEARCH CENTER 4 00:00:21,366 --> 00:00:26,366 AND THE DIRECTOR'S COLLOQUIUM SUMMER SERIES. 5 00:00:26,366 --> 00:00:29,766 WE FIRST ACHIEVED HUMAN LANDING 6 00:00:29,766 --> 00:00:34,300 ON THE MOON IN 1969. 7 00:00:34,300 --> 00:00:37,633 AT THE SAME TIME, VON BRAUN AND OTHERS 8 00:00:37,633 --> 00:00:40,433 PITCHED THE IDEA OF GOING TO MARS 9 00:00:40,433 --> 00:00:43,833 TO THE PRESIDENT OF THE UNITED STATES. 10 00:00:43,833 --> 00:00:47,866 THE QUESTION IS: WHY MARS? 11 00:00:47,866 --> 00:00:51,133 FIRST, IT'S OUR NEAREST NEIGHBOR, RIGHT? 12 00:00:51,133 --> 00:00:55,766 IT'S THE NEXT-PLANET NEIGHBOR, VENUS AND MARS. 13 00:00:55,766 --> 00:01:01,733 SECOND, IT IS A WAY FOR US TO UNDERSTAND OUR PAST 14 00:01:01,733 --> 00:01:06,066 BY STUDYING THE NEIGHBORS THAT ARE NEXT TO US. 15 00:01:06,066 --> 00:01:11,733 IT'S ALSO POTENTIALLY A PLACE TO COLONIZE IN THE FUTURE. 16 00:01:11,733 --> 00:01:15,900 BUT I ALWAYS SAY THAT SCIENCE-FICTION DRIVES REALITY. 17 00:01:15,900 --> 00:01:18,500 WHEN WE FIRST STARTED LOOKING AT MARS, 18 00:01:18,500 --> 00:01:21,833 WE SAW WHAT LOOKED LIKE CANALS AND CHANNELS 19 00:01:21,833 --> 00:01:23,900 THAT ARE THERE CHANGING, 20 00:01:23,900 --> 00:01:25,400 AND WE ENVISIONED THAT THERE ARE PEOPLE 21 00:01:25,400 --> 00:01:27,500 ON THAT PLANET. 22 00:01:27,500 --> 00:01:29,133 SOME EVEN ENVISIONED 23 00:01:29,133 --> 00:01:34,333 ATTACKS FROM MARS ON OUR PLANET. 24 00:01:34,333 --> 00:01:38,666 SO FAR, WE HAVE HAD MANY MISSIONS TO MARS, 25 00:01:38,666 --> 00:01:42,633 ROBOTIC MISSIONS THAT ARE EXPLORING MARS. 26 00:01:42,633 --> 00:01:45,366 BUT I PERSONALLY, AND MANY OTHERS, 27 00:01:45,366 --> 00:01:48,033 WANT TO SEE US THERE, 28 00:01:48,033 --> 00:01:52,633 SEE HUMANS GO TO MARS. 29 00:01:52,633 --> 00:01:55,533 WHEN DO WE DO THIS? 30 00:01:55,533 --> 00:01:59,833 DO WE WAIT UNTIL WE'VE RESOLVED ALL ISSUES, 31 00:01:59,833 --> 00:02:03,733 UNTIL WE KNOW WE HAVE NO MORE TECHNOLOGY DEVELOPMENT? 32 00:02:03,733 --> 00:02:08,600 OR DO WE DECIDE A CERTAIN DATE BY WHICH WE STOP 33 00:02:08,600 --> 00:02:12,333 AND TAKE OUR TECHNOLOGY THAT WE HAVE AND TAKE SOME RISKS 34 00:02:12,333 --> 00:02:16,900 AND GO TO MARS? 35 00:02:16,900 --> 00:02:19,933 WHEN YOU TAKE THOSE MISSIONS, YOU WILL LEARN, 36 00:02:19,933 --> 00:02:21,466 AND AS YOU LEARN FROM THOSE MISSIONS, 37 00:02:21,466 --> 00:02:24,266 YOU COULD HAVE SAFER TRAVELS TO MARS 38 00:02:24,266 --> 00:02:28,533 AND POTENTIALLY OTHER PLANETS. 39 00:02:28,533 --> 00:02:31,366 TODAY'S TALK IS ENTITLED 40 00:02:31,366 --> 00:02:38,133 "MARS DIRECT: HUMANS TO THE RED PLANET WITHIN A DECADE." 41 00:02:38,133 --> 00:02:42,433 IT WILL BE PRESENTED BY DR. ROBERT ZUBRIN, 42 00:02:42,433 --> 00:02:47,033 WHO IS THE PRESIDENT OF PIONEER ASTRONAUTICS 43 00:02:47,033 --> 00:02:50,633 AND ALSO THE SPIN-OFF PIONEER ENERGY. 44 00:02:50,633 --> 00:02:54,800 HE IS A FELLOW OF THE BRITISH INTERPLANETARY SOCIETY 45 00:02:54,800 --> 00:02:58,133 AND THE FOUNDER AND PRESIDENT OF MARS SOCIETY. 46 00:03:00,933 --> 00:03:03,966 HE HAS INVENTED SEVERAL UNIQUE CONCEPTS 47 00:03:03,966 --> 00:03:06,966 FOR SPACE PROPULSION AND EXPLORATION, 48 00:03:06,966 --> 00:03:11,866 THE AUTHOR OF HUNDREDS OF PUBLICATIONS, 49 00:03:11,866 --> 00:03:14,766 TECHNICAL PUBLICATIONS AND NON-TECHNICAL PUBLICATIONS, 50 00:03:14,766 --> 00:03:19,733 INCLUDING NONFICTION AND FICTION BOOKS. 51 00:03:19,733 --> 00:03:23,400 PLEASE JOIN ME IN WELCOMING ROBERT ZUBRIN. 52 00:03:23,400 --> 00:03:26,966 [applause] 53 00:03:31,433 --> 00:03:32,966 - OKAY. 54 00:03:32,966 --> 00:03:35,366 SO, THANK YOU FOR THAT KIND INTRODUCTION 55 00:03:35,366 --> 00:03:37,866 AND FOR INVITING ME TO COME AND SPEAK HERE. 56 00:03:37,866 --> 00:03:39,500 AND THANKS TO ALL OF YOU FOR COMING, 57 00:03:39,500 --> 00:03:41,000 LISTENING TO WHAT I'VE GOT TO SAY, 58 00:03:41,000 --> 00:03:42,833 AND MORE IMPORTANTLY, FOR WHAT YOU'RE DOING, 59 00:03:42,833 --> 00:03:46,566 BECAUSE I THINK THAT THIS TASK OF OPENING SPACE, 60 00:03:46,566 --> 00:03:48,133 OPENING THE UNIVERSE TO HUMANITY 61 00:03:48,133 --> 00:03:50,533 IS THE MOST IMPORTANT THING GOING ON IN THE WORLD 62 00:03:50,533 --> 00:03:51,533 AT THIS TIME. 63 00:03:51,533 --> 00:03:54,000 THIS TIME WILL BE REMEMBERED 64 00:03:54,000 --> 00:03:56,033 BECAUSE THIS IS WHEN WE FIRST SET SAIL 65 00:03:56,033 --> 00:03:57,700 FOR OTHER WORLDS. 66 00:03:57,700 --> 00:04:03,300 I'M GONNA TALK HUMANS TO MARS WITHIN A DECADE, OKAY? 67 00:04:03,300 --> 00:04:08,866 AND I'M GONNA TALK A LITTLE BIT 68 00:04:08,866 --> 00:04:11,966 ABOUT WHY I THINK IT WOULD HAVE TO BE DONE 69 00:04:11,966 --> 00:04:14,300 IN THAT KIND OF TIME FRAME IF YOU'RE GOING TO DO IT. 70 00:04:14,300 --> 00:04:15,800 I'M GONNA TALK AT SOME LENGTH 71 00:04:15,800 --> 00:04:17,466 AS TO HOW I THINK IT COULD BE DONE. 72 00:04:17,466 --> 00:04:18,600 IN FACT, I'M GOING TO SHOW YOU 73 00:04:18,600 --> 00:04:19,966 TWO DIFFERENT WAYS IT COULD BE DONE, 74 00:04:19,966 --> 00:04:21,300 A PREFERRED WAY 75 00:04:21,300 --> 00:04:24,900 AND ANOTHER WAY THAT WOULD ALSO WORK, 76 00:04:24,900 --> 00:04:29,966 ALTHOUGH IT PUSHES THE LIMITS OF MINIMALISM TO DO IT. 77 00:04:29,966 --> 00:04:33,800 AND FINALLY, I'LL TALK A LITTLE BIT 78 00:04:33,800 --> 00:04:35,533 ABOUT WHY IT NEEDS TO BE DONE AT ALL. 79 00:04:35,533 --> 00:04:36,633 AND BY THE WAY, IF YOU WANT TO HEAR MORE 80 00:04:36,633 --> 00:04:38,833 ON ESPECIALLY THAT LATTER SUBJECT, 81 00:04:38,833 --> 00:04:41,733 THE MARS SOCIETY IS HAVING ITS CONFERENCE IN HOUSTON 82 00:04:41,733 --> 00:04:43,366 AUGUST 7TH THROUGH 10TH. 83 00:04:43,366 --> 00:04:44,866 YOU'RE ALL INVITED TO COME. 84 00:04:44,866 --> 00:04:46,466 THERE'LL BE ALL KINDS OF TALKS THERE 85 00:04:46,466 --> 00:04:49,800 ABOUT WHY AND HOW WE CAN GO TO MARS. 86 00:04:49,800 --> 00:04:54,133 SO, HUMANS TO MARS WITHIN A DECADE, OKAY? 87 00:04:54,133 --> 00:04:56,433 IS THAT REALLY POSSIBLE? 88 00:04:56,433 --> 00:04:58,866 NASA'S CURRENT, I MEAN, TIMELINE 89 00:04:58,866 --> 00:05:02,066 IS TO DO IT AROUND THE YEAR 2047, 90 00:05:02,066 --> 00:05:03,733 MAYBE 3047. 91 00:05:03,733 --> 00:05:05,433 [laughter] 92 00:05:05,433 --> 00:05:11,166 THE QUESTION OF WHETHER WE CAN DO 93 00:05:11,166 --> 00:05:12,666 HUMANS TO MARS IN TEN YEARS 94 00:05:12,666 --> 00:05:15,500 IS SOMEWHAT ANALOGOUS TO THE QUESTION OF, 95 00:05:15,500 --> 00:05:17,866 "HOW MUCH ROPE DOES IT TAKE TO CONNECT TWO POSTS 96 00:05:17,866 --> 00:05:20,366 SEPARATED BY A DISTANCE OF 10 METERS?" 97 00:05:20,366 --> 00:05:23,333 IN PRINCIPLE, IT CAN BE DONE WITH 10 METERS OF ROPE. 98 00:05:23,333 --> 00:05:24,633 ON THE OTHER HAND, IF YOU LET THE ROPE 99 00:05:24,633 --> 00:05:26,033 BE TANGLED EVERY WHICH WAY, 100 00:05:26,033 --> 00:05:28,233 IT COULD TAKE AN INFINITE AMOUNT OF ROPE, OKAY, 101 00:05:28,233 --> 00:05:32,500 AND SO THE ANSWER TO THE QUESTION IS DEPENDENT 102 00:05:32,500 --> 00:05:34,500 UPON WHETHER YOU ACTUALLY WANT TO CONNECT THE TWO POSTS 103 00:05:34,500 --> 00:05:37,733 OR WHETHER YOU'RE TRYING TO SELL ROPE. 104 00:05:37,733 --> 00:05:40,566 AND "MARS DIRECT" WAS ACTUALLY CONCEIVED 105 00:05:40,566 --> 00:05:42,600 BY A TEAM LED BY ME 106 00:05:42,600 --> 00:05:44,866 AND ANOTHER ENGINEER NAMED DAVID BAKER 107 00:05:44,866 --> 00:05:47,633 AT MARTIN MARIETTA, WHICH BECAME LOCKHEED MARTIN, 108 00:05:47,633 --> 00:05:50,400 IN 1990 IN RESPONSE TO THE FAILURE, 109 00:05:50,400 --> 00:05:52,133 OR THE IMMINENT FAILURE-- 110 00:05:52,133 --> 00:05:53,966 AT THAT TIME, IT HADN'T QUITE FAILED YET-- 111 00:05:53,966 --> 00:05:57,600 OF THE FIRST PRESIDENT BUSH'S SPACE EXPLORATION INITIATIVE, 112 00:05:57,600 --> 00:06:00,200 WHICH WAS FOUNDERING BASED ON STICKER SHOCK 113 00:06:00,200 --> 00:06:01,933 DUE TO THE 90-DAY REPORT 114 00:06:01,933 --> 00:06:04,066 WHICH HAD POSTULATED A 30-YEAR PROGRAM 115 00:06:04,066 --> 00:06:05,466 COSTING $400 BILLION 116 00:06:05,466 --> 00:06:08,966 AND ALL SORTS OF EXERCISES IN INFRASTRUCTURE 117 00:06:08,966 --> 00:06:11,933 AND TECHNOLOGY DEVELOPMENTS BEFORE WE COULD GET TO MARS. 118 00:06:11,933 --> 00:06:15,633 AND IT WAS VERY CLEAR TO US AT MARTIN 119 00:06:15,633 --> 00:06:18,666 THAT THE REASON WHY THE 90-DAY REPORT 120 00:06:18,666 --> 00:06:21,133 WAS SO LONG AND COSTLY AND COMPLEX 121 00:06:21,133 --> 00:06:24,133 WAS THAT IT WAS-- HAD BEEN DESIGNED 122 00:06:24,133 --> 00:06:28,600 WITH THE IDEA OF MAKING A WHOLE BUNCH OF PEOPLE HAPPY, 123 00:06:28,600 --> 00:06:30,733 PEOPLE DEVELOPING THIS TECHNOLOGY AND THAT TECHNOLOGY 124 00:06:30,733 --> 00:06:33,333 IN THIS CENTER AND THAT CENTER OR THIS COMPANY OR THAT COMPANY 125 00:06:33,333 --> 00:06:35,100 OR HERE OR THERE OR EVERYWHERE. 126 00:06:35,100 --> 00:06:37,233 THEY HAD BASICALLY NOT DESIGNED A MISSION 127 00:06:37,233 --> 00:06:38,333 BUT A CHRISTMAS TREE 128 00:06:38,333 --> 00:06:39,933 UPON WHICH TO HANG ALL THE ORNAMENTS 129 00:06:39,933 --> 00:06:42,533 AND, YOU KNOW, PROVIDE BUSINESS FOR EVERYONE. 130 00:06:42,533 --> 00:06:44,700 AND THAT'S THE EXACT OPPOSITE 131 00:06:44,700 --> 00:06:46,800 OF THE CORRECT WAY TO DO ENGINEERING, OKAY? 132 00:06:46,800 --> 00:06:48,733 YOU DON'T DESIGN SOMETHING 133 00:06:48,733 --> 00:06:51,400 TO BE AS COMPLEX AND COSTLY AS POSSIBLE 134 00:06:51,400 --> 00:06:53,200 IN ORDER TO PLEASE YOUR VENDORS. 135 00:06:53,200 --> 00:06:56,166 YOU DESIGN IT TO BE AS SIMPLE AS POSSIBLE 136 00:06:56,166 --> 00:06:58,066 AND AS INEXPENSIVE AS POSSIBLE 137 00:06:58,066 --> 00:07:01,933 IN ORDER TO DO THE JOB MOST EFFICIENTLY. 138 00:07:01,933 --> 00:07:03,666 SO THE QUESTION WE ASKED OURSELVES 139 00:07:03,666 --> 00:07:04,966 WHEN WE DESIGNED "MARS DIRECT" 140 00:07:04,966 --> 00:07:06,800 IS, IF YOU WANTED TO DESIGN A MARS MISSION 141 00:07:06,800 --> 00:07:10,200 AND NOT PROVIDE EXCUSES FOR PEOPLE WHO WANTED, YOU KNOW, 142 00:07:10,200 --> 00:07:11,366 TO USE THIS TECHNOLOGY, 143 00:07:11,366 --> 00:07:12,533 WANTED TO USE ELECTRIC PROPULSION, 144 00:07:12,533 --> 00:07:14,033 WANTED TO USE NUCLEAR PROPULSION, 145 00:07:14,033 --> 00:07:15,533 WANTED TO USE THIS, WANTED TO USE THAT, 146 00:07:15,533 --> 00:07:16,900 WANTED TO USE BIOREGENERATIVE LIFE SUPPORT 147 00:07:16,900 --> 00:07:18,666 AND PHYSICAL LIFE SUPPORT AND THIS 148 00:07:18,666 --> 00:07:19,800 AND HAVE A LUNAR BASE 149 00:07:19,800 --> 00:07:21,166 AND HAVE A HANGAR ON THE SPACE STATION 150 00:07:21,166 --> 00:07:25,333 AND, YOU KNOW, THE ABILITY TO REUSE RL-10 ENGINES IN ORBIT, 151 00:07:25,333 --> 00:07:26,633 AND WHATEVER, 152 00:07:26,633 --> 00:07:27,966 HOW WOULD YOU DO IT 153 00:07:27,966 --> 00:07:31,033 IF YOU JUST WANTED TO GET THE JOB DONE, OKAY? 154 00:07:31,033 --> 00:07:34,300 AND THAT IS THE QUESTION WE ASKED OURSELVES. 155 00:07:34,300 --> 00:07:37,533 SO, FIRST, I'M GOING TO NOW PRESENT THE DESIGN 156 00:07:37,533 --> 00:07:42,766 AS WE DEVELOPED IT IN THE SPRING OF 1990. 157 00:07:42,766 --> 00:07:44,233 OKAY. 158 00:07:44,233 --> 00:07:46,733 THIS IS THE MISSION SEQUENCE CHART 159 00:07:46,733 --> 00:07:49,033 FOR THE "MARS DIRECT" PLAN. 160 00:07:49,033 --> 00:07:51,033 YOU CAN LAUNCH TO MARS EVERY TWO YEARS, 161 00:07:51,033 --> 00:07:52,600 SO WE'RE GOING TO BE LAUNCHING TWO BOOSTERS 162 00:07:52,600 --> 00:07:57,933 EVERY TWO YEARS TO MARS IN ORDER TO DO THIS. 163 00:07:57,933 --> 00:08:00,833 WELL, FIRST OF ALL, ANY SPACE OPERATION 164 00:08:00,833 --> 00:08:02,700 REQUIRES AN APPROPRIATE LAUNCH VEHICLE, 165 00:08:02,700 --> 00:08:05,900 AND WE SET OURSELVES THE TASK OF DESIGNING ONE 166 00:08:05,900 --> 00:08:09,300 IN THE SATURN V CLASS OUT OF AVAILABLE TECHNOLOGY, 167 00:08:09,300 --> 00:08:11,533 SHUTTLE TECHNOLOGY. 168 00:08:11,533 --> 00:08:13,933 AND ACTUALLY IT'S NOT VERY DIFFERENT FROM THE SLS 169 00:08:13,933 --> 00:08:18,600 THAT IS CURRENTLY BEING DEVELOPED BY NASA. 170 00:08:18,600 --> 00:08:20,300 I MEAN, WE'RE USING SHUTTLE MAIN ENGINES 171 00:08:20,300 --> 00:08:22,066 INSTEAD OF SOME OTHER MAIN ENGINES AT THE BOTTOM, 172 00:08:22,066 --> 00:08:23,500 AND THEY'RE OFFSET A LITTLE BIT 173 00:08:23,500 --> 00:08:25,333 BECAUSE THESE WERE GOING TO BE LAUNCHED 174 00:08:25,333 --> 00:08:26,733 IN PARALLEL WITH THE SHUTTLE, 175 00:08:26,733 --> 00:08:29,400 WHICH HAS ITS FLAME TRENCHES POSITIONED THUS. 176 00:08:29,400 --> 00:08:30,900 BUT, BASICALLY, HERE YOU GO. 177 00:08:30,900 --> 00:08:33,633 YOU HAVE FOUR SHUTTLE MAIN ENGINES, A COUPLE SOLIDS, 178 00:08:33,633 --> 00:08:35,166 THE EXTERNAL TANK CORE, 179 00:08:35,166 --> 00:08:37,266 HYDROGEN-OXYGEN UPPER STAGE, 180 00:08:37,266 --> 00:08:38,600 AND A 10-METER FAIRING, 181 00:08:38,600 --> 00:08:42,600 OR 33 FEET IF YOU WORK AT LOCKHEED MARTIN. 182 00:08:42,600 --> 00:08:46,500 AND THE--OKAY. 183 00:08:46,500 --> 00:08:50,033 AND THIS COULD LIFT 120 TONS TO LOW EARTH ORBIT, 184 00:08:50,033 --> 00:08:51,566 BUT MORE IMPORTANTLY, 185 00:08:51,566 --> 00:08:57,266 IT COULD USE THIS UPPER STAGE TO SEND 47 TONS 186 00:08:57,266 --> 00:08:59,000 ON DIRECT TRANS-MARS INJECTION 187 00:08:59,000 --> 00:09:01,600 OR 59 TONS ON TRANS-LUNAR INJECTION. 188 00:09:01,600 --> 00:09:03,866 AND THAT IS HOW WE WANTED TO DO THE MISSION, 189 00:09:03,866 --> 00:09:05,366 JUST LIFT AND THROW AND LET IT GO, 190 00:09:05,366 --> 00:09:06,866 SEND THE PAYLOAD TO THE PLANET, 191 00:09:06,866 --> 00:09:10,400 THE SAME BOOSTER THAT LAUNCHED IT IN THE FIRST PLACE. 192 00:09:10,400 --> 00:09:11,500 THAT'S HOW WE'VE DONE 193 00:09:11,500 --> 00:09:13,333 EVERY REAL, UNMANNED PLANETARY MISSION, 194 00:09:13,333 --> 00:09:15,800 THAT'S HOW WE DID THE REAL APOLLO MISSIONS TO THE MOON. 195 00:09:15,800 --> 00:09:17,800 NO ONE'S EVER DONE A MISSION TO ANYWHERE 196 00:09:17,800 --> 00:09:19,600 BY LIFTING THINGS TO THE SPACE STATION 197 00:09:19,600 --> 00:09:21,233 AND WAITING FOR THE INTERPLANETARY CRUISER 198 00:09:21,233 --> 00:09:22,566 TO RETURN FROM SATURN 199 00:09:22,566 --> 00:09:24,400 AND BE REFITTED TO LOAD THE PAYLOAD ON IT 200 00:09:24,400 --> 00:09:25,666 AND THEN GO BACK OUT. 201 00:09:25,666 --> 00:09:27,866 NO, JUST LIFT AND THROW AND LET IT GO. 202 00:09:27,866 --> 00:09:30,100 AND RIGHT THERE, IF YOU CAN DO THE MISSION THAT WAY, 203 00:09:30,100 --> 00:09:32,833 YOU'VE GONE 90% OF THE WAY TOWARDS TAKING THE MARS MISSION 204 00:09:32,833 --> 00:09:34,500 OUT OF THE SCIENCE-FICTION FUTURE 205 00:09:34,500 --> 00:09:37,633 AND PUTTING IT IN OUR WORLD OF REAL ENGINEERING. 206 00:09:37,633 --> 00:09:39,566 BUT HOW CAN YOU DO THAT? 207 00:09:39,566 --> 00:09:44,000 THE TYPICAL MARS MISSION DESIGNS THAT WERE AROUND 208 00:09:44,000 --> 00:09:48,066 WERE 700 TO 1,000 TONS IN LEO. 209 00:09:48,066 --> 00:09:49,833 THIS IS 120 TONS IN LEO, 210 00:09:49,833 --> 00:09:51,800 WHICH, BY THE WAY, IS A LITTLE LESS THAN A SATURN V, 211 00:09:51,800 --> 00:09:54,966 WHICH COULD DO 140. 212 00:09:54,966 --> 00:09:56,533 YOU KNOW, A BOOSTER THAT COULD LAUNCH 213 00:09:56,533 --> 00:10:00,066 ONE OF THESE DEATH STAR SPACESHIP CONCEPTS, 214 00:10:00,066 --> 00:10:02,133 YOU'D BLOW AWAY ORLANDO WHEN YOU TOOK OFF. 215 00:10:02,133 --> 00:10:05,233 SO HOW COULD YOU DO THIS MISSION 216 00:10:05,233 --> 00:10:07,500 WITH A SATURN V CLASS BOOSTER? 217 00:10:07,500 --> 00:10:10,166 WELL, IF YOU LOOKED AT THESE OTHER MISSION PLANS, 218 00:10:10,166 --> 00:10:11,900 WHAT YOU SAW WAS THAT THE MAJORITY OF THE MASS 219 00:10:11,900 --> 00:10:13,266 THAT THEY WERE SENDING TO MARS 220 00:10:13,266 --> 00:10:15,800 WAS THE PROPELLANT TO COME BACK. 221 00:10:15,800 --> 00:10:17,933 WELL, THAT MAY SEEM PRUDENT, OKAY? 222 00:10:17,933 --> 00:10:19,166 SHOULDN'T YOU GO TO MARS 223 00:10:19,166 --> 00:10:21,900 AND HAVE THE PROPELLANT TO COME BACK? 224 00:10:21,900 --> 00:10:24,466 WELL, IS THAT HOW WE'VE EXPLORED ON EARTH? 225 00:10:24,466 --> 00:10:27,700 DID LEWIS AND CLARK CROSS THE AMERICAN CONTINENT 226 00:10:27,700 --> 00:10:29,866 BRINGING WITH THEM ALL THE FOOD, WATER, AND AIR 227 00:10:29,866 --> 00:10:32,100 THEY WOULD NEED FOR THEMSELVES AND THEIR HORSES 228 00:10:32,100 --> 00:10:33,333 FOR A THREE-YEAR TRANSCONTINENTAL 229 00:10:33,333 --> 00:10:34,333 TRIP OF EXPLORATION? 230 00:10:34,333 --> 00:10:35,333 NO. 231 00:10:35,333 --> 00:10:36,600 IF THEY HAD DONE THAT, 232 00:10:36,600 --> 00:10:38,266 THEY WOULD HAVE NEEDED A WAGON TRAIN OF SUPPLIES 233 00:10:38,266 --> 00:10:39,266 FOR EVERY MAN 234 00:10:39,266 --> 00:10:41,166 AND ANOTHER WAGON TRAIN FOR EVERY HORSE, 235 00:10:41,166 --> 00:10:43,233 AND THEN, OF COURSE, THE WAGON TRAIN MEN AND HORSES 236 00:10:43,233 --> 00:10:44,833 WOULD HAVE NEEDED FURTHER WAGON TRAINS, 237 00:10:44,833 --> 00:10:46,400 AND IT WOULD HAVE GONE EXPONENTIAL. 238 00:10:46,400 --> 00:10:47,966 AND NOT ONLY WOULD IT HAVE BLOWN THE BUDGET 239 00:10:47,966 --> 00:10:49,633 OF THOMAS JEFFERSON'S AMERICA, 240 00:10:49,633 --> 00:10:52,900 IT WOULD HAVE EXCEEDED THE MASS OF THE EARTH. 241 00:10:52,900 --> 00:10:57,266 OKAY, NOW, THE--BUT NO, THAT'S NOT WHAT THEY DID. 242 00:10:57,266 --> 00:10:59,266 THEY HUNTED THEIR WAY ACROSS, 243 00:10:59,266 --> 00:11:02,733 AND IN CERTAIN WAYS THEY TRADED WITH NATIVE AMERICANS 244 00:11:02,733 --> 00:11:04,433 TO OBTAIN NECESSARY SUPPLIES. 245 00:11:04,433 --> 00:11:06,166 BUT IN EITHER CASE, THEY WERE MAKING USE 246 00:11:06,166 --> 00:11:08,166 OF THE RESOURCES THAT WERE AVAILABLE 247 00:11:08,166 --> 00:11:10,966 IN THE ENVIRONMENT THEY INTENDED TO OPERATE IN. 248 00:11:10,966 --> 00:11:12,366 WELL, WHY ARE WE GOING TO MARS? 249 00:11:12,366 --> 00:11:14,100 WE'RE GOING TO MARS BECAUSE MARS IS THE PLANET 250 00:11:14,100 --> 00:11:16,433 THAT HAS THE RESOURCES THAT CAN SUPPORT LIFE 251 00:11:16,433 --> 00:11:19,633 AND, THEREFORE, POTENTIALLY TECHNOLOGICAL CIVILIZATION. 252 00:11:19,633 --> 00:11:23,100 WELL, THE SAME RESOURCES THAT MAKE MARS INTERESTING, 253 00:11:23,100 --> 00:11:25,733 IF YOU MAKE USE OF THEM, CAN ALSO MAKE IT ATTAINABLE. 254 00:11:25,733 --> 00:11:28,566 SO THAT IS THE ORIENTATION WE TOOK HERE. 255 00:11:28,566 --> 00:11:31,033 WHAT IS THE TRAVEL-LIGHT, LIVE-OFF-THE-LAND APPROACH 256 00:11:31,033 --> 00:11:33,600 TO MARS EXPLORATION? 257 00:11:33,600 --> 00:11:38,700 SO THE FIRST THING THAT WE SEND TO MARS, 258 00:11:38,700 --> 00:11:41,166 THE FIRST LAUNCH, HERE, 259 00:11:41,166 --> 00:11:43,966 SENDS OUT ON A MINIMUM-ENERGY TRAJECTORY 260 00:11:43,966 --> 00:11:46,966 A EARTH RETURN VEHICLE, ERV. 261 00:11:46,966 --> 00:11:48,833 AND WHAT THIS IS, THIS IS A LITTLE ROCKET SHIP 262 00:11:48,833 --> 00:11:50,433 FOR RETURNING FROM MARS TO EARTH 263 00:11:50,433 --> 00:11:51,966 IN THE TERMINAL STAGE OF THE MISSION. 264 00:11:51,966 --> 00:11:54,233 BUT NO ONE'S IN IT WHEN IT GOES OUT THE FIRST TIME. 265 00:11:54,233 --> 00:11:56,133 SO IT IS UNMANNED. 266 00:11:56,133 --> 00:11:58,900 IT'S GOT A LITTLE CABIN HERE, 15 FEET IN DIAMETER, 267 00:11:58,900 --> 00:12:03,000 WITH SPARTAN QUARTERS FOR A CREW OF FOUR 268 00:12:03,000 --> 00:12:05,233 FOR A SIX-MONTH VOYAGE FROM MARS BACK TO EARTH. 269 00:12:05,233 --> 00:12:07,100 THEN IT'S GOT TWO METHANE OXYGEN 270 00:12:07,100 --> 00:12:10,900 CHEMICAL PROPULSION STAGES HERE WHICH ARE UNFUELED. 271 00:12:10,900 --> 00:12:12,300 THEY HAVE TO BE UNFUELED, 272 00:12:12,300 --> 00:12:13,566 OR THIS WILL WEIGH MUCH TOO HEAVY 273 00:12:13,566 --> 00:12:16,966 FOR SOMETHING LIKE A SATURN V CLASS BOOSTER 274 00:12:16,966 --> 00:12:18,333 TO THROW TO MARS. 275 00:12:18,333 --> 00:12:19,833 HOWEVER, IN SOME OF THE LOWER STAGE TANKS 276 00:12:19,833 --> 00:12:21,933 THAT ARE LATER GOING TO CONTAIN METHANE, 277 00:12:21,933 --> 00:12:23,833 WE'VE GOT ABOUT 6 TONS OF LIQUID HYDROGEN 278 00:12:23,833 --> 00:12:25,300 PROBABLY IN GEL FORM, 279 00:12:25,300 --> 00:12:26,600 AND THEN SLUNG BELOW THE VEHICLE, 280 00:12:26,600 --> 00:12:28,100 NOT SHOWN IN THIS DIAGRAM, 281 00:12:28,100 --> 00:12:29,300 IS A LITTLE TRUCK, A LIGHT TRUCK, 282 00:12:29,300 --> 00:12:30,666 LIKE A LITTLE PICKUP TRUCK. 283 00:12:30,666 --> 00:12:34,133 IN THE BACK OF THAT TRUCK IS A LITTLE NUCLEAR REACTOR 284 00:12:34,133 --> 00:12:36,166 WITH A POWER OF 100 KILOWATTS. 285 00:12:36,166 --> 00:12:38,666 OKAY, 100 KILOWATTS IS LIKE 130 HORSEPOWER, 286 00:12:38,666 --> 00:12:41,166 SAME AMOUNT OF POWER THAT POWERS A MEDIUM-SIZE CAR. 287 00:12:41,166 --> 00:12:43,400 OKAY, SO IT'S NOT A GIANT NUCLEAR POWER PLANT 288 00:12:43,400 --> 00:12:44,500 THAT POWERS A CITY. 289 00:12:44,500 --> 00:12:45,900 IT'S JUST A NICE LITTLE PUTT-PUTT NUKE 290 00:12:45,900 --> 00:12:47,500 SITTING IN THE BACK OF A TRUCK. 291 00:12:47,500 --> 00:12:50,266 NOW, AFTER YOU'VE LANDED, 292 00:12:50,266 --> 00:12:51,966 THE TRUCK IS TELEROBOTICALLY DRIVEN 293 00:12:51,966 --> 00:12:53,466 A FEW HUNDRED METERS AWAY, 294 00:12:53,466 --> 00:12:55,666 UNWINDING A CABLE OFF THE BACK OF IT AS IT GOES, 295 00:12:55,666 --> 00:12:57,300 AND THEN THE REACTOR'S PUT ON THE GROUND, 296 00:12:57,300 --> 00:12:58,900 PREFERABLY IN A DITCH OR A CRATER 297 00:12:58,900 --> 00:13:00,266 ON THE REVERSE SIDE OF THE HILL, 298 00:13:00,266 --> 00:13:01,833 ANYTHING TO PUT A NICE-SIZE CHUNK OF DIRT 299 00:13:01,833 --> 00:13:03,833 BETWEEN THE REACTOR AND THE MAIN LANDING AREA. 300 00:13:03,833 --> 00:13:05,100 AND THEN YOU GOT POWER AT THE SHIP. 301 00:13:05,100 --> 00:13:07,766 YOU TURN IT ON, OKAY, AND WHAT YOU DO THEN IS, 302 00:13:07,766 --> 00:13:10,500 YOU RUN A PUMP, AND YOU SUCK IN THE MARTIAN AIR, 303 00:13:10,500 --> 00:13:13,033 WHICH IS 95% CARBON DIOXIDE, 304 00:13:13,033 --> 00:13:14,300 AND YOU REACT THAT 305 00:13:14,300 --> 00:13:16,400 WITH THE HYDROGEN THAT YOU BROUGHT FROM EARTH, 306 00:13:16,400 --> 00:13:20,100 AND HYDROGEN CAN BE REACTED WITH CARBON DIOXIDE 307 00:13:20,100 --> 00:13:22,500 IN THE PRESENCE OF EITHER RUTHENIUM OR NICKEL 308 00:13:22,500 --> 00:13:25,633 ON ALUMINA CATALYST TO PRODUCE METHANE AND WATER. 309 00:13:25,633 --> 00:13:27,100 THAT'S KNOWN AS SABATIER REACTION. 310 00:13:27,100 --> 00:13:28,733 METHANE'S GOOD ROCKET FUEL. YOU STORE THAT. 311 00:13:28,733 --> 00:13:30,433 YOU TAKE THE WATER, YOU ELECTROLYZE IT, 312 00:13:30,433 --> 00:13:32,766 SPLIT IT INTO HYDROGEN AND OXYGEN. 313 00:13:32,766 --> 00:13:35,900 OH, HERE'S THE WHOLE DIAGRAM. 314 00:13:35,900 --> 00:13:39,300 AND SO THIS MAKES METHANE AND WATER. 315 00:13:39,300 --> 00:13:41,466 THE WATER IS ELECTROLYZED, GIVES YOU OXYGEN. 316 00:13:41,466 --> 00:13:42,733 HYDROGEN IS RECYCLED. 317 00:13:42,733 --> 00:13:45,733 THEN, TO MAKE ADDITIONAL OXYGEN, YOU HAVE A THIRD REACTOR 318 00:13:45,733 --> 00:13:47,833 IN WHICH YOU SPLIT CARBON DIOXIDE 319 00:13:47,833 --> 00:13:49,366 INTO CARBON MONOXIDE AND OXYGEN, 320 00:13:49,366 --> 00:13:51,366 KEEP THE OXYGEN, DUMP THE CARBON MONOXIDE. 321 00:13:51,366 --> 00:13:52,600 YOU CAN DO THAT ON MARS. 322 00:13:52,600 --> 00:13:54,900 THERE'S NO EPA THERE, 323 00:13:54,900 --> 00:13:58,533 WHICH IS A SUBSTANTIAL GOOD REASON TO GO TO MARS. 324 00:13:58,533 --> 00:14:01,466 [laughter] 325 00:14:01,466 --> 00:14:03,500 AND NOW YOU'VE GOT A FULLY FUELED EARTH RETURN VEHICLE 326 00:14:03,500 --> 00:14:05,366 SITTING, WAITING FOR YOU ON THE SURFACE OF MARS. 327 00:14:05,366 --> 00:14:07,000 AND, IN FACT, WE MAKE EXTRA PROPELLANT 328 00:14:07,000 --> 00:14:08,966 BEYOND WHAT THE EARTH RETURN VEHICLE NEEDS 329 00:14:08,966 --> 00:14:12,333 SO THAT WE CAN OPERATE CHEMICAL-POWERED VEHICLES 330 00:14:12,333 --> 00:14:14,600 ON THE SURFACE OF MARS FOR EXPLORATION PURPOSES. 331 00:14:14,600 --> 00:14:15,800 AND WHY DO WE WANT TO DO THAT? 332 00:14:15,800 --> 00:14:17,333 BECAUSE WE'RE GOING TO MARS TO EXPLORE, 333 00:14:17,333 --> 00:14:20,900 AND CHEMICAL-REACTION VEHICLES 334 00:14:20,900 --> 00:14:23,300 HAVE A MUCH HIGHER POWER-TO-MASS RATIO 335 00:14:23,300 --> 00:14:25,600 THAN YOU CAN GET WITH ELECTRIC VEHICLES OR R.T.G. VEHICLES 336 00:14:25,600 --> 00:14:27,100 OR ANYTHING OF THAT SORT, 337 00:14:27,100 --> 00:14:30,466 WHICH IS WHY THEY'RE SO MUCH MORE POPULAR HERE ON EARTH. 338 00:14:30,466 --> 00:14:32,200 AND IN A FRONTIER ENVIRONMENT LIKE MARS, 339 00:14:32,200 --> 00:14:34,333 WHERE YOU REALLY WANT THE SPEED, THE LONG RANGE, THE TORQUE, 340 00:14:34,333 --> 00:14:35,666 THE HAULING CAPABILITY, 341 00:14:35,666 --> 00:14:38,033 AND ALL-AROUND MUSCLE YOU GET FROM HAVING A REAL CAR 342 00:14:38,033 --> 00:14:39,200 INSTEAD OF A GOLF CART, 343 00:14:39,200 --> 00:14:40,333 YOU REALLY WANT TO HAVE ONE. 344 00:14:40,333 --> 00:14:41,600 BUT IT WOULDN'T BE PRACTICAL 345 00:14:41,600 --> 00:14:43,233 IF YOU HAD TO BRING THE FUEL FROM EARTH. 346 00:14:43,233 --> 00:14:44,866 BUT BECAUSE YOU CAN MAKE THE FUEL ON MARS, 347 00:14:44,866 --> 00:14:46,966 THEN YOU HAVE THIS ADDITIONAL CAPABILITY. 348 00:14:46,966 --> 00:14:48,666 SO THE POINT HERE IS THAT THE ABILITY 349 00:14:48,666 --> 00:14:50,266 TO MAKE USE OF LOCAL RESOURCES 350 00:14:50,266 --> 00:14:52,500 IS NOT JUST THE KEY TO MAKING THE MISSION CHEAP. 351 00:14:52,500 --> 00:14:54,333 IT'S ALSO THE KEY TO MAKING THE MISSION EFFECTIVE, 352 00:14:54,333 --> 00:14:56,233 WHICH IS EVEN MORE IMPORTANT, ACTUALLY, 353 00:14:56,233 --> 00:14:57,733 BECAUSE THERE'S NO POINT GOING TO MARS 354 00:14:57,733 --> 00:15:01,666 UNLESS YOU CAN DO SOMETHING USEFUL ONCE YOU GET THERE. 355 00:15:01,666 --> 00:15:04,066 SO, OKAY, THE NEXT-- 356 00:15:04,066 --> 00:15:05,933 THIS BEING DONE, 357 00:15:05,933 --> 00:15:07,933 AT THE NEXT LAUNCH OPPORTUNITY, TWO YEARS LATER, 358 00:15:07,933 --> 00:15:09,766 WE LAUNCH TWO MORE BOOSTERS OFF THE CAPE. 359 00:15:09,766 --> 00:15:11,666 ONE SENDS OUT ANOTHER EARTH RETURN VEHICLE. 360 00:15:11,666 --> 00:15:13,000 THE OTHER SHOOTS OUT A HAB 361 00:15:13,000 --> 00:15:15,500 WITH A CREW OF FOUR ASTRONAUTS IN IT. 362 00:15:15,500 --> 00:15:17,633 NOW, BECAUSE OUR RETURN RIDE 363 00:15:17,633 --> 00:15:19,400 IS WAITING FOR US ON THE SURFACE OF MARS, 364 00:15:19,400 --> 00:15:20,566 WE DON'T NEED TO FLY TO MARS 365 00:15:20,566 --> 00:15:22,933 IN A GIGANTIC DEATH STAR SPACESHIP, OKAY? 366 00:15:22,933 --> 00:15:24,233 WE DON'T EVEN HAVE TO FLY OUT 367 00:15:24,233 --> 00:15:26,733 IN A COMPARATIVELY MODEST "MILLENNIUM FALCON." 368 00:15:26,733 --> 00:15:29,600 WE CAN FLY TO MARS IN A TUNA CAN. 369 00:15:29,600 --> 00:15:32,766 AND THAT'S A VERY GOOD THING, 370 00:15:32,766 --> 00:15:34,500 BECAUSE WE KNOW HOW TO BUILD THEM 371 00:15:34,500 --> 00:15:36,366 AND THEY'VE BEEN PROVEN IN INDUSTRY 372 00:15:36,366 --> 00:15:38,700 TO BE A VERY EFFECTIVE FORM OF PACKAGING. 373 00:15:38,700 --> 00:15:41,066 NOW, OURS IS SOMEWHAT LARGER 374 00:15:41,066 --> 00:15:43,633 THAN THE CHICKEN OF THE SEA UNIT. 375 00:15:43,633 --> 00:15:47,466 OKAY, THIS IS 8 1/2 METERS, 27 FEET IN DIAMETER. 376 00:15:47,466 --> 00:15:50,700 TWO DECKS, EACH WITH 8 FEET OF HEADROOM. 377 00:15:50,700 --> 00:15:52,233 UPPER DECK IS WHERE THEY LIVE. 378 00:15:52,233 --> 00:15:54,366 LOWER DECK IS MORE OF A CARGO HOLD, 379 00:15:54,366 --> 00:15:56,233 WORKSHOP KIND OF PLACE. 380 00:15:56,233 --> 00:15:59,866 HERE'S ONE POTENTIAL LAYOUT OF THE UPPER DECK. 381 00:15:59,866 --> 00:16:01,433 FOUR LITTLE STATEROOMS. 382 00:16:01,433 --> 00:16:04,566 THERE'S A CREW OF FOUR IN HERE, IF I DIDN'T MENTION THAT. 383 00:16:04,566 --> 00:16:06,900 SCIENCE AREA, GALLEY, EXERCISE AREA, 384 00:16:06,900 --> 00:16:10,133 AND IN THE CENTER IS A SOLAR FLARE STORM SHELTER. 385 00:16:10,133 --> 00:16:12,233 OKAY, THERE'S TWO KINDS OF RADIATION 386 00:16:12,233 --> 00:16:13,833 THAT CAN GET YOU IN SPACE: 387 00:16:13,833 --> 00:16:15,700 SOLAR FLARES, COSMIC RAYS. 388 00:16:15,700 --> 00:16:17,333 SOLAR FLARES COME FROM THE SUN, 389 00:16:17,333 --> 00:16:20,266 BIG PULSES OF RADIATION IN AN UNPREDICTABLE WAY. 390 00:16:20,266 --> 00:16:23,366 THAT IS, YOU DON'T KNOW WHEN IT'S GONNA HAPPEN, 391 00:16:23,366 --> 00:16:25,033 MAYBE ONE BIG ONE A YEAR. 392 00:16:25,033 --> 00:16:27,000 BUT THEY'RE BASICALLY PROTONS 393 00:16:27,000 --> 00:16:28,766 WITH ENERGIES OF ABOUT A MEGAVOLT 394 00:16:28,766 --> 00:16:31,066 THAT CAN BE STOPPED BY 5 INCHES OF WATER. 395 00:16:31,066 --> 00:16:34,000 AND WE HAVE ENOUGH PROVISIONS ON THE SHIP TO MASS THAT OUT. 396 00:16:34,000 --> 00:16:36,300 SO THAT'S HOW YOU'RE SAFE AGAINST THE SOLAR FLARES. 397 00:16:36,300 --> 00:16:39,566 THE COSMIC RAYS, WHICH ARE A LITTLE PITTER-PATTER CONSTANTLY 398 00:16:39,566 --> 00:16:41,033 OF HIGH-ENERGY RADIATION 399 00:16:41,033 --> 00:16:42,733 COMING IN FROM INTERSTELLAR SPACE, 400 00:16:42,733 --> 00:16:45,033 THAT CANNOT BE STOPPED WITH 5 INCHES OF WATER, 401 00:16:45,033 --> 00:16:47,033 BUT THE DOSE FOR THAT IS MODERATE, 402 00:16:47,033 --> 00:16:48,633 AS I WILL SHOW YOU LATER, 403 00:16:48,633 --> 00:16:49,900 THAT THIS IS-- 404 00:16:49,900 --> 00:16:52,200 YOU'RE GONNA TAKE THIS WHEN YOU GO TO MARS 405 00:16:52,200 --> 00:16:54,200 NO MATTER WHAT YOU DO, 406 00:16:54,200 --> 00:16:55,933 BUT IT REPRESENTS A MODEST PORTION 407 00:16:55,933 --> 00:16:59,100 OF OVERALL MISSION RISK. 408 00:16:59,100 --> 00:17:01,933 NOW, LET ME JUST SAY THIS, BY THE WAY. 409 00:17:01,933 --> 00:17:04,366 THE TRAJECTORY THAT WE'RE GOING OUT TO MARS ON 410 00:17:04,366 --> 00:17:06,566 IS A SIX-MONTH TRAJECTORY. 411 00:17:06,566 --> 00:17:08,900 AND THIS IS THE CORRECT TRAJECTORY 412 00:17:08,900 --> 00:17:10,400 TO SEND PEOPLE TO MARS ON 413 00:17:10,400 --> 00:17:13,433 REGARDLESS OF THE PROPULSION SYSTEM THAT YOU HAVE. 414 00:17:13,433 --> 00:17:15,466 THAT IS, THERE'S PEOPLE GOING AROUND SAYING, 415 00:17:15,466 --> 00:17:17,533 "WE'VE GOT TO GO TO MARS FASTER. WE'VE GOT TO GO TO MARS FASTER. 416 00:17:17,533 --> 00:17:19,766 "IF WE HAD NUCLEAR THERMAL ROCKETS, 417 00:17:19,766 --> 00:17:21,266 WE COULD GET TO MARS IN FOUR MONTHS." 418 00:17:21,266 --> 00:17:25,133 WELL, YOU COULD, BUT YOU SHOULDN'T. 419 00:17:25,133 --> 00:17:26,633 IF YOU HAD NUCLEAR THERMAL ROCKETS, 420 00:17:26,633 --> 00:17:28,033 YOU SHOULD GET TO MARS IN SIX MONTHS 421 00:17:28,033 --> 00:17:29,866 AND USE THE SUPERIOR PROPULSION CAPABILITY 422 00:17:29,866 --> 00:17:31,866 TO DOUBLE YOUR PAYLOAD, OKAY? 423 00:17:31,866 --> 00:17:32,866 WHY? 424 00:17:32,866 --> 00:17:33,900 WELL, THERE'S TWO REASONS. 425 00:17:33,900 --> 00:17:35,400 ONE IS, DOUBLING THE PAYLOAD 426 00:17:35,400 --> 00:17:37,500 WILL DO FAR MORE FOR MISSION SAFETY 427 00:17:37,500 --> 00:17:40,766 THAN REDUCING THE TRANSIT TIME BY TWO MONTHS, OKAY. 428 00:17:40,766 --> 00:17:43,000 IN TERMS OF MORE REDUNDANCY, 429 00:17:43,000 --> 00:17:45,866 OF CRITICAL SYSTEMS AND SO FORTH, THAT'S POSSIBLE. 430 00:17:45,866 --> 00:17:47,766 BUT THE OTHER IS THIS. 431 00:17:47,766 --> 00:17:49,800 SIX MONTHS OUTBOUND TRANSIT 432 00:17:49,800 --> 00:17:52,800 IS THE TWO-YEAR FREE RETURN TRAJECTORY TO EARTH. 433 00:17:52,800 --> 00:17:54,400 SO IF YOU HAVE TO ABORT THE MISSION, 434 00:17:54,400 --> 00:17:55,666 YOU CAN FLY BY MARS, COME BACK, 435 00:17:55,666 --> 00:17:56,766 YOU GET BACK TO EARTH'S ORBIT 436 00:17:56,766 --> 00:17:58,866 EXACTLY TWO YEARS AFTER YOU LEFT IT, 437 00:17:58,866 --> 00:18:00,266 AND EARTH WILL BE THERE. 438 00:18:00,266 --> 00:18:02,166 IF YOU TRY TO GO TO MARS FASTER, 439 00:18:02,166 --> 00:18:04,566 YOU NECESSARILY GO OUT FURTHER ON A FREE RETURN. 440 00:18:04,566 --> 00:18:06,433 YOU COME BACK IN MORE THAN TWO YEARS, 441 00:18:06,433 --> 00:18:08,300 AND EARTH IS NOT THERE, OKAY? 442 00:18:08,300 --> 00:18:13,033 SO, BY TRYING TO GO TO MARS FASTER THAN SIX MONTHS, 443 00:18:13,033 --> 00:18:16,900 YOU LOSE ROBUSTNESS AND YOU LOSE THE FREE RETURN, 444 00:18:16,900 --> 00:18:18,866 SO YOU SHOULDN'T DO IT, OKAY? 445 00:18:18,866 --> 00:18:20,266 BETTER PROPULSION IS BETTER, 446 00:18:20,266 --> 00:18:22,300 BUT USE IT TO INCREASE THE PAYLOAD. 447 00:18:22,300 --> 00:18:24,033 OKAY. 448 00:18:24,033 --> 00:18:28,000 NOW, THE ONE HEALTH EFFECT THAT WE REALLY HAVE SEEN IN SPACE 449 00:18:28,000 --> 00:18:29,266 HAS NOT BEEN FROM RADIATION. 450 00:18:29,266 --> 00:18:31,333 IT'S BEEN FROM ZERO GRAVITY. 451 00:18:31,333 --> 00:18:36,200 OKAY, AND SO WE MAKE ARTIFICIAL GRAVITY ON THE SHIP 452 00:18:36,200 --> 00:18:38,333 BY TETHERING OFF THE BURNT-OUT UPPER STAGE. 453 00:18:38,333 --> 00:18:40,533 THIS IS THE BURNT-OUT UPPER STAGE OF THE ARES BOOSTER. 454 00:18:40,533 --> 00:18:41,800 IT THREW US TO MARS. 455 00:18:41,800 --> 00:18:43,066 IT'S COASTING TO MARS TOO. 456 00:18:43,066 --> 00:18:44,133 IT CAN BE USED AS A COUNTERWEIGHT 457 00:18:44,133 --> 00:18:45,300 ON THE END OF A TETHER. 458 00:18:45,300 --> 00:18:47,900 THIS THING IS ABOUT A MILE LONG, 1,500 METERS. 459 00:18:47,900 --> 00:18:51,333 SPIN THIS AT 1 RPM, YOU GET MARS GRAVITY IN THE HAB. 460 00:18:51,333 --> 00:18:53,433 IF YOU SPUN IT AT A LITTLE LESS THAN 2 RPM, 461 00:18:53,433 --> 00:18:54,933 YOU'D HAVE EARTH GRAVITY IN THE HAB 462 00:18:54,933 --> 00:18:58,466 AND AVOID THE DECONDITIONING ASSOCIATED WITH ZERO GRAVITY 463 00:18:58,466 --> 00:19:02,366 AND OTHER HEALTH EFFECTS, EYE EFFECTS AND SO FORTH, 464 00:19:02,366 --> 00:19:03,700 THAT HAVE BEEN IDENTIFIED. 465 00:19:03,700 --> 00:19:05,900 THOSE ARE THE SERIOUS HEALTH EFFECTS OF SPACE FLIGHT, 466 00:19:05,900 --> 00:19:09,500 AND THEY CAN BE AMELIORATED THIS WAY. 467 00:19:09,500 --> 00:19:13,466 OKAY, SO-- I DON'T KNOW WHY THAT'S THERE. 468 00:19:13,466 --> 00:19:15,466 OH, I KNOW WHY IT'S THERE. 469 00:19:15,466 --> 00:19:17,966 OKAY, SO THEY FLY OUT TO MARS, TAKE SIX MONTHS. 470 00:19:17,966 --> 00:19:20,400 THEY FIRE PYRO, CUT THE CABLE, AERO-BRAKE, 471 00:19:20,400 --> 00:19:22,266 AND GO AND LAND AT LANDING SITE NUMBER ONE, 472 00:19:22,266 --> 00:19:24,000 WHERE THE FULLY FUELED EARTH RETURN VEHICLE 473 00:19:24,000 --> 00:19:25,333 IS WAITING FOR THEM. 474 00:19:25,333 --> 00:19:26,966 OKAY. 475 00:19:26,966 --> 00:19:28,466 IF THEY LAND OFF-COURSE, 476 00:19:28,466 --> 00:19:30,933 THEY'VE GOT A PRESSURIZED ROVER IN THE LOWER DECK OF THE HAB. 477 00:19:30,933 --> 00:19:32,900 IT HAS A ONE-WAY RANGE OF 600 MILES, 478 00:19:32,900 --> 00:19:34,666 SO THEY REALLY SHOULD BE ABLE TO ACHIEVE 479 00:19:34,666 --> 00:19:36,133 THIS SURFACE RENDEZVOUS. 480 00:19:36,133 --> 00:19:37,866 IF THEY CAN'T, THEY HAVE A REAL PROBLEM 481 00:19:37,866 --> 00:19:40,500 WITH THE PILOT SELECTION PROCESS. 482 00:19:40,500 --> 00:19:43,366 AND IF THAT'S THE CASE, WE CAN STILL SAVE THE MISSION 483 00:19:43,366 --> 00:19:45,033 BY TAKING THE SECOND EARTH RETURN VEHICLE 484 00:19:45,033 --> 00:19:46,733 AND LANDING IT NEAR THEM. 485 00:19:46,733 --> 00:19:50,433 BUT, ASSUMING THAT THEY DO LAND CORRECTLY, 486 00:19:50,433 --> 00:19:53,366 THE SECOND EARTH RETURN VEHICLE CAN BE LANDED ANYWHERE ELSE, 487 00:19:53,366 --> 00:19:54,866 COULD BE LANDED CLOSE BY, 488 00:19:54,866 --> 00:19:56,166 COULD BE ON THE OTHER SIDE OF THE PLANET, 489 00:19:56,166 --> 00:19:58,833 BUT I WOULD LAND IT A FEW HUNDRED MILES AWAY, 490 00:19:58,833 --> 00:20:00,000 BECAUSE IT WILL DEFINE 491 00:20:00,000 --> 00:20:02,166 WHERE THE NEXT EXPLORATION MISSION GOES. 492 00:20:02,166 --> 00:20:04,133 BUT I WOULD STILL LIKE IT TO BE 493 00:20:04,133 --> 00:20:05,633 WITHIN AT LEAST ONE-WAY DRIVING RANGE 494 00:20:05,633 --> 00:20:07,800 OF THE AVAILABLE GROUND TRANSPORTATION. 495 00:20:07,800 --> 00:20:10,133 SO THE CREW HAS TWO COMPLETE EARTH RETURN VEHICLES, 496 00:20:10,133 --> 00:20:11,800 EITHER ONE OF WHICH COULD TAKE THEM HOME. 497 00:20:11,800 --> 00:20:13,766 AND THEY HAVE THREE HABITABLE VOLUMES, 498 00:20:13,766 --> 00:20:14,900 THE BIG ONE IN THE HAB 499 00:20:14,900 --> 00:20:16,666 AND THE CABINS OF THE TWO ERVs. 500 00:20:16,666 --> 00:20:18,866 SO THEY'RE MULTIPLY BACKED UP IN THAT WAY. 501 00:20:18,866 --> 00:20:22,133 BUT THE REAL PURPOSE OF THIS ERV IS NOT FOR THEM. 502 00:20:22,133 --> 00:20:24,566 IT'S TO START MAKING PROPELLANT TO SUPPORT THE NEXT MISSION, 503 00:20:24,566 --> 00:20:26,266 WHICH FLIES OUT TWO YEARS LATER, 504 00:20:26,266 --> 00:20:28,200 ALONG WITH ANOTHER ERV, WHICH IS THEIR BACKUP, 505 00:20:28,200 --> 00:20:32,900 BUT WHICH OTHERWISE OPENS UP LANDING SITE NUMBER THREE. 506 00:20:32,900 --> 00:20:35,500 SO THIS IS AN ACTUAL PHOTOGRAPH OF THE BASE. 507 00:20:35,500 --> 00:20:37,900 [laughter] 508 00:20:37,900 --> 00:20:41,833 WHAT YOU SEE HERE, HERE IS THE EARTH RETURN VEHICLE. 509 00:20:41,833 --> 00:20:43,800 THERE'S THE CABIN, THE TWO PROPULSION STAGES, 510 00:20:43,800 --> 00:20:47,566 THE INTAKES FOR THE CHEMICAL PROCESSING UNIT, 511 00:20:47,566 --> 00:20:49,200 WHICH IS BUILT INTO THE LANDING STAGE 512 00:20:49,200 --> 00:20:51,366 THAT ACTS AS THE TAKEOFF PAD FOR THE REST OF IT. 513 00:20:51,366 --> 00:20:53,366 HERE'S THE REACTOR AND THE CRATER IN THE BACKGROUND, 514 00:20:53,366 --> 00:20:55,366 THE HABITAT, UPPER STAGE WHERE THEY LIVE, 515 00:20:55,366 --> 00:20:57,266 UPPER DECK WHERE THEY LIVE. 516 00:20:57,266 --> 00:20:58,433 LOWER DECK IS THE GARAGE 517 00:20:58,433 --> 00:21:00,166 FOR THE LITTLE PRESSURIZED ROVER, 518 00:21:00,166 --> 00:21:02,033 COUPLE OF SOLAR PANELS USED AS BACKUP POWER 519 00:21:02,033 --> 00:21:03,400 IF YOU HAVE TO TURN THE REACTOR OFF. 520 00:21:03,400 --> 00:21:04,433 YOU ALSO HAVE BACKUP POWER 521 00:21:04,433 --> 00:21:05,966 BY RUNNING THE ENGINE OF THE ROVER 522 00:21:05,966 --> 00:21:07,500 OR THE LIGHT TRUCK, 523 00:21:07,500 --> 00:21:09,466 WHICH MAY BE HARD TO SEE, BUT IT'S SITTING OVER HERE. 524 00:21:09,466 --> 00:21:10,733 IT'S AN UNPRESSURIZED VEHICLE 525 00:21:10,733 --> 00:21:12,366 WHICH IS ALSO THE BACKUP FOR THIS ONE. 526 00:21:12,366 --> 00:21:15,166 AND THEN THIS THING HERE IS AN INFLATABLE GREENHOUSE. 527 00:21:15,166 --> 00:21:16,900 THIS IS NOT A MISSION-CRITICAL ELEMENT. 528 00:21:16,900 --> 00:21:19,766 IT'S AN EXPERIMENT IN LEARNING HOW TO GROW CROPS ON MARS 529 00:21:19,766 --> 00:21:21,666 IN MARTIAN SOIL, MARTIAN SUNLIGHT, 530 00:21:21,666 --> 00:21:23,566 MARTIAN GRAVITY, MARTIAN WATER, 531 00:21:23,566 --> 00:21:27,900 FOR THE BENEFIT OF FUTURE MISSIONS AND FUTURE BASES. 532 00:21:27,900 --> 00:21:30,900 NOW, AFTER A NUMBER OF THESE MISSIONS HAVE OCCURRED 533 00:21:30,900 --> 00:21:32,200 IN DIFFERENT PLACES, 534 00:21:32,200 --> 00:21:35,466 YOU'LL KNOW WHERE YOU WANT TO DEVELOP A MAJOR BASE, 535 00:21:35,466 --> 00:21:38,800 AND YOU COULD DO THAT BY LANDING A LOT OF THE HABS 536 00:21:38,800 --> 00:21:41,566 IN THE SAME PLACE AND MATING THEM UP. 537 00:21:41,566 --> 00:21:43,166 THESE ARE SECOND-GENERATION HABS HERE 538 00:21:43,166 --> 00:21:46,300 WHOSE LANDING LEGS CAN ARTICULATE 539 00:21:46,300 --> 00:21:49,800 NOT ONLY UP AND DOWN BUT ALSO SIDE-TO-SIDE, 540 00:21:49,800 --> 00:21:52,233 THUS ALLOWING THEM TO WALK MUCH IN THE MANNER 541 00:21:52,233 --> 00:21:55,833 THAT THE MARTIANS DID IN "THE WAR OF THE WORLDS." 542 00:21:55,833 --> 00:21:58,000 SO THIS HAS HERITAGE. 543 00:21:58,000 --> 00:22:00,133 [laughter] 544 00:22:00,133 --> 00:22:02,200 AND THERE IT IS. 545 00:22:02,200 --> 00:22:04,533 AND I DON'T HAVE TIME TO GO INTO IT, 546 00:22:04,533 --> 00:22:05,800 BUT I'LL ASSERT WITHOUT PROOF 547 00:22:05,800 --> 00:22:07,433 THAT WE COULD USE THE SAME FLIGHT ELEMENTS 548 00:22:07,433 --> 00:22:09,166 TO BUILD A LUNAR BASE TOO, 549 00:22:09,166 --> 00:22:11,700 SO WE COULD DO THESE THINGS IN PARALLEL, OKAY. 550 00:22:11,700 --> 00:22:13,966 WE DON'T BUILD A LUNAR BASE IN ORDER TO GO TO MARS. 551 00:22:13,966 --> 00:22:15,933 YOU DON'T NEED A LUNAR BASE TO GO TO MARS. 552 00:22:15,933 --> 00:22:18,700 BUT, IN FACT, IF YOU WANTED TO MAINTAIN THE FLIGHT RATE 553 00:22:18,700 --> 00:22:21,833 ASSOCIATED WITH HAVING AN ACTIVE BOOSTER PROGRAM, 554 00:22:21,833 --> 00:22:24,133 YOU DON'T WANT TO BE LAUNCHING TWO EVERY TWO YEARS. 555 00:22:24,133 --> 00:22:26,600 YOU NEED TO LAUNCH MORE FREQUENTLY THAN THAT, 556 00:22:26,600 --> 00:22:28,633 OR, FRANKLY, YOU'RE WASTING A LOT OF MONEY 557 00:22:28,633 --> 00:22:30,866 BY HAVING A STANDING ARMY SITTING AROUND DOING NOTHING 558 00:22:30,866 --> 00:22:32,733 AND, IN FACT, GETTING OUT OF PRACTICE. 559 00:22:32,733 --> 00:22:34,466 SO YOU WOULD PROBABLY ACTUALLY DO THESE THINGS 560 00:22:34,466 --> 00:22:37,133 AT THE SAME TIME. 561 00:22:37,133 --> 00:22:40,366 AND SO THIS IS THE HARDWARE SET THAT WE NEED 562 00:22:40,366 --> 00:22:42,866 TO OPEN UP TWO NEW WORLDS. 563 00:22:42,866 --> 00:22:46,133 NOW, OKAY, THAT'S HOW I'D LIKE TO DO MARS, 564 00:22:46,133 --> 00:22:47,533 AND I THINK WE CAN DO THAT. 565 00:22:47,533 --> 00:22:54,866 HOWEVER, RECENTLY, YOU KNOW, 566 00:22:54,866 --> 00:22:56,433 SPACEX HAS COME ALONG, 567 00:22:56,433 --> 00:22:58,500 AND THEY ARE DEVELOPING HARDWARE 568 00:22:58,500 --> 00:23:01,500 THAT'S GOING TO BE DEVELOPED RELATIVELY SOON, 569 00:23:01,500 --> 00:23:02,966 OR SO IT WOULD SEEM, 570 00:23:02,966 --> 00:23:05,566 INCLUDING FALCON HEAVY CAPABLE OF LAUNCHING 50 TONS 571 00:23:05,566 --> 00:23:07,866 TO LOW EARTH ORBIT. 572 00:23:07,866 --> 00:23:12,066 NOW, 50 TONS IS NOT 120. IT'S LESS. 573 00:23:12,066 --> 00:23:14,733 IT IS. 574 00:23:14,733 --> 00:23:17,966 AND--BUT, YOU KNOW, I SET MYSELF THE TASK OF SAYING, 575 00:23:17,966 --> 00:23:20,233 "WELL, LOOK, WHAT IF I DIDN'T HAVE WHAT I WANT? 576 00:23:20,233 --> 00:23:22,866 "WHAT IF I HAVE THAT? 577 00:23:22,866 --> 00:23:25,300 "OKAY, CAN WE STILL DO HUMANS TO MARS? 578 00:23:25,300 --> 00:23:27,700 IS THERE A WAY THAT, YOU KNOW--" 579 00:23:27,700 --> 00:23:29,033 IN OTHER WORDS, THIS IS NOT AN IDEAL WORLD. 580 00:23:29,033 --> 00:23:30,100 YOU'VE GOT TO, YOU KNOW-- 581 00:23:30,100 --> 00:23:31,366 AS DONALD RUMSFELD SAID, 582 00:23:31,366 --> 00:23:32,833 "YOU GO TO WAR WITH THE FORCES YOU GOT." 583 00:23:32,833 --> 00:23:36,233 OKAY, HE'S AN AUTHORITY. 584 00:23:36,233 --> 00:23:40,900 AND, ANYWAY, YOU GO TO MARS WITH THE FORCES YOU GOT. 585 00:23:40,900 --> 00:23:42,333 SO HOW WOULD I DO IT? 586 00:23:42,333 --> 00:23:45,966 WELL, FIRST OF ALL, I WOULD TAKE AN ALTERATION OF THIS PLAN 587 00:23:45,966 --> 00:23:48,233 WHICH I CALL THE "MARS SEMI-DIRECT" PLAN. 588 00:23:48,233 --> 00:23:50,533 AND THIS, BY THE WAY, IS THE MISSION ARCHITECTURE 589 00:23:50,533 --> 00:23:53,066 THAT WAS ADOPTED BY NASA JOHNSON SPACE CENTER 590 00:23:53,066 --> 00:23:56,100 AND WAS D.R., DESIGN REFERENCE, MISSION 3. 591 00:23:56,100 --> 00:23:59,033 OKAY, THIS IS A THREE-LAUNCH MISSION ARCHITECTURE, OKAY, 592 00:23:59,033 --> 00:24:01,533 IN WHICH ONE LAUNCH SENDS TO MARS 593 00:24:01,533 --> 00:24:09,033 THE EARTH-MARS ASCENT VEHICLE, 594 00:24:09,033 --> 00:24:10,233 WHICH GOES TO THE SURFACE 595 00:24:10,233 --> 00:24:12,066 AND MAKES PROPELLANT ON THE SURFACE. 596 00:24:12,066 --> 00:24:17,100 ONE SENDS THE HAB OUT WITH A CREW, 597 00:24:17,100 --> 00:24:19,600 AND ONE SENDS AN EARTH RETURN VEHICLE 598 00:24:19,600 --> 00:24:24,766 TO A HIGHLY ELLIPTICAL, LOOSELY BOUND MARS ORBIT, 599 00:24:24,766 --> 00:24:27,166 AND SO THAT THE MISSION PLAN IS, 600 00:24:27,166 --> 00:24:29,500 FIRST, YOU SEND AN ASCENT VEHICLE 601 00:24:29,500 --> 00:24:31,600 WHICH FUELS ITSELF ON THE SURFACE, 602 00:24:31,600 --> 00:24:33,766 WHOSE PROCESS IS SIMILAR TO "MARS DIRECT." 603 00:24:33,766 --> 00:24:35,900 OKAY, AND THEN, IN THE NEXT LAUNCH OPPORTUNITY, 604 00:24:35,900 --> 00:24:39,833 YOU SEND OUT AN EARTH RETURN VEHICLE AND A HAB. 605 00:24:39,833 --> 00:24:44,333 NOW, IN FACT, THIS WOULD REQUIRE THREE FALCON HEAVIES, 606 00:24:44,333 --> 00:24:46,333 SO IT'S THREE LAUNCHES, OKAY. 607 00:24:46,333 --> 00:24:47,933 AND WHAT WE DID HERE WAS, 608 00:24:47,933 --> 00:24:50,300 THE FIRST TIME, I WOULD SEND ALL THESE ELEMENTS OUT, 609 00:24:50,300 --> 00:24:51,933 BUT WITH NO ONE IN ANY OF THEM, 610 00:24:51,933 --> 00:24:53,433 AND THEN AT THE SECOND OPPORTUNITY, 611 00:24:53,433 --> 00:24:57,866 YOU SEND OUT THE CREW IN A HAB THAT RENDEZVOUS ON THE SURFACE 612 00:24:57,866 --> 00:25:00,233 WITH THE ASCENT VEHICLE 613 00:25:00,233 --> 00:25:03,133 AND ANOTHER EARTH RETURN VEHICLE TO POSITION IN MARS ORBIT 614 00:25:03,133 --> 00:25:04,966 AND ANOTHER ASCENT VEHICLE. 615 00:25:04,966 --> 00:25:09,133 SO THE--AND THEN THE CREW ASCENDS TO ORBIT 616 00:25:09,133 --> 00:25:11,566 AT THE END OF A YEAR AND A HALF ON THE MARTIAN SURFACE 617 00:25:11,566 --> 00:25:13,733 IN THE PRE-POSITIONED ASCENT VEHICLE. 618 00:25:13,733 --> 00:25:15,800 AND WHILE THE OTHER ONE IS THERE MAKING PROPELLANT, 619 00:25:15,800 --> 00:25:17,400 THEN, IN FACT, IT'S A BACKUP FOR THEM. 620 00:25:17,400 --> 00:25:19,666 AND THE PRE-POSITIONED HAB IS THERE 621 00:25:19,666 --> 00:25:21,533 SO THAT WHEN THEY LAND IN THEIR HAB, 622 00:25:21,533 --> 00:25:23,266 THERE'S ACTUALLY TWO HABS. 623 00:25:23,266 --> 00:25:28,466 NOW, WHAT WE-- WHAT I ASSUMED FOR THIS 624 00:25:28,466 --> 00:25:31,233 IS THAT WE HAD, ALSO, THE DRAGON 625 00:25:31,233 --> 00:25:32,966 WITH A LONG-DURATION LIFE SUPPORT SYSTEM 626 00:25:32,966 --> 00:25:35,866 INSTALLED IN IT. 627 00:25:35,866 --> 00:25:38,100 NOW, THE DRAGON IS KIND OF SMALL 628 00:25:38,100 --> 00:25:43,166 FOR LONG-DURATION HABITATION, 629 00:25:43,166 --> 00:25:47,700 SO THE NOTION HERE WAS THAT AN INFLATABLE EXTENSION 630 00:25:47,700 --> 00:25:49,700 FOR THE DRAGON COULD BE MADE THAT WOULD-- 631 00:25:49,700 --> 00:25:53,200 IN OTHER WORDS, THE CREW COULD LAUNCH TO ORBIT IN A DRAGON, 632 00:25:53,200 --> 00:25:55,966 AND THEN HERE IT IS. 633 00:25:55,966 --> 00:25:58,366 IT TURNS AROUND, DOES THE APOLLO MANEUVER, 634 00:25:58,366 --> 00:26:03,433 AND PULLS OUT OF HERE, OR THE INFLATABLE, 635 00:26:03,433 --> 00:26:05,733 AND ALSO A TETHER THAT GOES TO THE UPPER STAGE 636 00:26:05,733 --> 00:26:11,333 AND CAN GIVE THIS ARTIFICIAL GRAVITY 637 00:26:11,333 --> 00:26:13,800 OFF THE TRANS-MARS INJECTION STAGE. 638 00:26:13,800 --> 00:26:17,366 NOW, I SAID I'D MENTION THIS BUSINESS ABOUT RADIATION, 639 00:26:17,366 --> 00:26:20,266 BECAUSE, ONCE AGAIN, THIS HAS REALLY BEEN USED 640 00:26:20,266 --> 00:26:25,200 AS A KIND OF SNOW DAY BY THOSE IN AUTHORITY 641 00:26:25,200 --> 00:26:26,800 WHO DON'T WANT TO GO TO MARS. 642 00:26:26,800 --> 00:26:29,166 IN OTHER WORDS, YOU KNOW, WE RECENTLY HAD 643 00:26:29,166 --> 00:26:32,033 RADIATION RESULTS FROM "CURIOSITY" IN TRANSIT 644 00:26:32,033 --> 00:26:36,333 WHICH WERE THE SAME AS THOSE FROM "MARIE" IN TRANSIT IN 2001. 645 00:26:36,333 --> 00:26:39,266 THE DATA WAS THE SAME, BUT IN 2001 THEY SAID, 646 00:26:39,266 --> 00:26:42,000 "THIS SHOWS THAT THE RADIATION DOSE OF GOING TO MARS 647 00:26:42,000 --> 00:26:43,900 IS A MODEST PORTION OF TOTAL MISSION RISK." 648 00:26:43,900 --> 00:26:46,166 THEN IN 2013, THEY SAID, 649 00:26:46,166 --> 00:26:52,500 "THIS SHOWS THAT WE CAN'T GO TO MARS--HA-HA, SNOW DAY." 650 00:26:52,500 --> 00:26:54,300 BUT, IN FACT, 651 00:26:54,300 --> 00:26:56,666 THE COSMIC RAY RADIATION DOSE RATES 652 00:26:56,666 --> 00:26:58,366 IN LOW EARTH ORBIT 653 00:26:58,366 --> 00:27:01,633 ARE HALF OF THOSE OF INTERPLANETARY SPACE. 654 00:27:01,633 --> 00:27:03,833 AND THIS IS BECAUSE THE EARTH'S MAGNETIC FIELD 655 00:27:03,833 --> 00:27:07,033 DOES NOT BLOCK AGAINST G-E-V COSMIC RAYS. 656 00:27:07,033 --> 00:27:09,500 THE EARTH BLOCKS OUT HALF THE SKY, 657 00:27:09,500 --> 00:27:11,366 AND THAT'S WHY IT'S A FACTOR OF TWO LESS. 658 00:27:11,366 --> 00:27:12,633 BUT IT'S THE SAME STUFF, 659 00:27:12,633 --> 00:27:13,800 AND IT'S JUST HALF THE DOSE RATE. 660 00:27:13,800 --> 00:27:15,066 AND, AS YOU CAN SEE, 661 00:27:15,066 --> 00:27:17,066 THERE'S ABOUT TEN COSMONAUTS AND ASTRONAUTS 662 00:27:17,066 --> 00:27:18,700 WHO HAVE RECEIVED, 663 00:27:18,700 --> 00:27:23,166 DUE TO LONG-DURATION ACTIVITY ON THE MIR OR THE SPACE STATION, 664 00:27:23,166 --> 00:27:25,433 COSMIC RAY DOSES THAT ARE QUITE COMPARABLE 665 00:27:25,433 --> 00:27:27,933 TO WHAT YOU WOULD GET DOING A ROUNDTRIP TO MARS. 666 00:27:27,933 --> 00:27:30,133 AND THERE HAVE BEEN NO RADIOLOGICAL CASUALTIES 667 00:27:30,133 --> 00:27:31,533 AMONG THIS GROUP. 668 00:27:31,533 --> 00:27:33,266 NOR WOULD WE EXPECT THERE TO HAVE BEEN, 669 00:27:33,266 --> 00:27:36,700 BECAUSE THE RADIATION RISK IS ABOUT 1%. 670 00:27:36,700 --> 00:27:42,133 AND SO THE IDEA THAT WE CANNOT GO TO MARS 671 00:27:42,133 --> 00:27:44,100 UNTIL MUCH MORE ADVANCED PROPULSION SYSTEMS 672 00:27:44,100 --> 00:27:46,300 THAT ARE AVAILABLE THAT CAN GET US TO MARS IN 30 DAYS 673 00:27:46,300 --> 00:27:50,600 IS NOT A VALID ARGUMENT, 674 00:27:50,600 --> 00:27:55,100 AND I BELIEVE IT'S DISINGENUOUS AS WELL. 675 00:27:55,100 --> 00:27:58,400 GIVEN THE FACT, GIVEN THE FACT, FIGURE IT OUT. 676 00:27:58,400 --> 00:28:00,500 OVER THE NEXT TEN YEARS, 677 00:28:00,500 --> 00:28:02,900 SPACE STATION WILL BE CONTINUALLY OCCUPIED, 678 00:28:02,900 --> 00:28:05,733 OKAY, WITH A CREW ABOUT THE SAME SIZE 679 00:28:05,733 --> 00:28:08,700 AS A MARS MISSION CREW, OKAY, 680 00:28:08,700 --> 00:28:11,466 SO TEN YEARS CONTINUAL OCCUPATION 681 00:28:11,466 --> 00:28:14,700 AT HALF THE DOSE RATE OF HUMAN MARS MISSIONS 682 00:28:14,700 --> 00:28:18,433 WHICH SPEND 40% OF THEIR TIME IN TRANSIT, OKAY. 683 00:28:18,433 --> 00:28:21,700 THE TOTAL NUMBER OF PERSON REMS BOTH PROGRAMS WOULD RECEIVE, 684 00:28:21,700 --> 00:28:23,266 THE SPACE STATION OVER THE NEXT TEN YEARS 685 00:28:23,266 --> 00:28:25,533 OR A PROGRAM OF SENDING FIVE HUMAN MISSIONS TO MARS 686 00:28:25,533 --> 00:28:26,900 OVER TEN YEARS, 687 00:28:26,900 --> 00:28:28,666 USING EVERY OPPORTUNITY FOR FLIGHT, 688 00:28:28,666 --> 00:28:30,433 IS THE SAME. 689 00:28:30,433 --> 00:28:32,033 SO RIGHT NOW, NASA, 690 00:28:32,033 --> 00:28:33,766 WHILE WAVING ITS HANDS IN HORROR 691 00:28:33,766 --> 00:28:35,500 OVER THE RADIATION RISK OF GOING TO MARS, 692 00:28:35,500 --> 00:28:37,733 IS ACTUALLY IMPOSING THAT SAME RADIATION RISK 693 00:28:37,733 --> 00:28:43,566 ON THEIR CREWS WITHOUT GOING ANYWHERE. 694 00:28:43,566 --> 00:28:47,700 NOW, ALL RIGHT. 695 00:28:47,700 --> 00:28:50,233 SO I WORKED OUT THE MASSES ON THIS, 696 00:28:50,233 --> 00:28:52,633 AND THE MARGINS ARE TIGHT, BUT THIS LOOKS DOABLE. 697 00:28:52,633 --> 00:28:56,100 ASSUMING 8 TONS, METRIC TONS, FOR THE DRAGONS THEMSELVES, 698 00:28:56,100 --> 00:28:58,200 YOU GO THROUGH THE VARIOUS CONSUMABLES. 699 00:28:58,200 --> 00:29:00,466 YOU HAVE TO HAVE WATER RECYCLING. 700 00:29:00,466 --> 00:29:05,400 AND THAT, BY THE WAY, IS KEY FOR ANY MARS MISSION, 701 00:29:05,400 --> 00:29:09,600 BECAUSE THE AMOUNT OF WATER THAT YOU USE, OKAY, 702 00:29:09,600 --> 00:29:12,900 NASA--WELL, AT LEAST IN SOME AMES DOCUMENTS 703 00:29:12,900 --> 00:29:14,533 THAT I SAW A DECADE AGO-- 704 00:29:14,533 --> 00:29:18,400 THEY WERE SAYING 32 KILOGRAMS PER DAY PER PERSON 705 00:29:18,400 --> 00:29:19,900 WITHOUT RECYCLING. 706 00:29:19,900 --> 00:29:23,266 IN OUR MARS--ARTIC AND MARS DESERT RESEARCH STATIONS, 707 00:29:23,266 --> 00:29:25,500 WE'VE BEEN ABLE TO GET IT DOWN TO 12 A DAY PER PERSON. 708 00:29:25,500 --> 00:29:30,033 BUT EVEN THERE, IF YOU HAVE FOUR PEOPLE 709 00:29:30,033 --> 00:29:32,000 AND ROUND IT OFF TO 1,000 DAYS, 710 00:29:32,000 --> 00:29:36,033 4,000 TIMES 12 WOULD BE 48 TONS OF WATER 711 00:29:36,033 --> 00:29:37,800 IF YOU HAD NO RECYCLING. 712 00:29:37,800 --> 00:29:40,933 IF YOU HAVE 90% RECYCLING, IT'S 4.8 TONS OF WATER. 713 00:29:40,933 --> 00:29:42,200 SO THAT BECOMES DOABLE, 714 00:29:42,200 --> 00:29:43,866 BUT YOU'VE GOT TO DO THAT. 715 00:29:43,866 --> 00:29:47,400 THE KEY TECHNOLOGY HERE IS WATER RECYCLING. 716 00:29:47,400 --> 00:29:50,233 IT'S NOT IMPORTANT TO MAKE YOUR FOOD. 717 00:29:50,233 --> 00:29:51,966 YOU CAN BRING YOUR FOOD. 718 00:29:51,966 --> 00:29:54,766 THAT IS A MODEST MASS. 719 00:29:54,766 --> 00:29:58,133 IT'S WATER THAT REALLY WEIGHS IT. 720 00:29:58,133 --> 00:30:00,400 AND, WELL, IT'S ALL HERE. 721 00:30:00,400 --> 00:30:05,766 NOW, THE CREW IS A CREW OF TWO. 722 00:30:05,766 --> 00:30:07,300 AND, BY THE WAY, IN DOING THIS, 723 00:30:07,300 --> 00:30:12,900 I ASSUMED TWO AVERAGE PEOPLE IN TERMS OF SIZE. 724 00:30:12,900 --> 00:30:17,233 NOW, THAT COULD BE ALTERED. 725 00:30:17,233 --> 00:30:19,866 WHY DO WE HAVE TO SEND AVERAGE-SIZE PEOPLE TO MARS? 726 00:30:19,866 --> 00:30:21,766 WHY NOT SEND SMALL PEOPLE? 727 00:30:21,766 --> 00:30:25,133 WE TRY TO MAKE EVERYTHING ELSE SMALL AND LIGHTWEIGHT 728 00:30:25,133 --> 00:30:26,433 ON THE MISSION, 729 00:30:26,433 --> 00:30:28,566 AND A 100-POUND PERSON EATS HALF AS MUCH 730 00:30:28,566 --> 00:30:31,400 AS A 200-POUND PERSON. 731 00:30:31,400 --> 00:30:34,266 AND SO, YOU KNOW, 732 00:30:34,266 --> 00:30:38,166 I UNDERSTAND THAT THERE ARE CULTURAL ISSUES HERE, 733 00:30:38,166 --> 00:30:40,866 BUT IF ONE WANTED TO BE PRACTICAL, 734 00:30:40,866 --> 00:30:43,833 YOU MIGHT START THINKING IN THOSE DIRECTIONS. 735 00:30:43,833 --> 00:30:45,366 AND, IN FACT, THOUGH, 736 00:30:45,366 --> 00:30:50,300 IF WE DID USE SMALL PEOPLE, 737 00:30:50,300 --> 00:30:53,500 WE PROBABLY COULD HAVE A CREW OF THREE. 738 00:30:56,300 --> 00:31:01,766 OKAY, AND THEN THIS IS JUST AN ARTIST'S DEPICTION 739 00:31:01,766 --> 00:31:03,366 OF THESE THINGS LANDED ON MARS. 740 00:31:03,366 --> 00:31:06,100 THE NOTION HERE IS THESE HABS. 741 00:31:06,100 --> 00:31:08,766 YOU DON'T DO ENTRY AND LANDING WITH THE HABS INFLATED. 742 00:31:08,766 --> 00:31:11,333 THEY WOULD BE DEFLATED, STUFFED BACK INSIDE, 743 00:31:11,333 --> 00:31:14,866 AND THEN INFLATED AGAIN ONCE THEY'RE ON THE SURFACE. 744 00:31:14,866 --> 00:31:16,666 AND THIS LOOKS VERY VULNERABLE 745 00:31:16,666 --> 00:31:18,466 TO BEING BLOWN OVER BY THE WIND OR SOMETHING, 746 00:31:18,466 --> 00:31:21,666 BUT, IN FACT, THE DYNAMIC PRESSURE OF WINDS 747 00:31:21,666 --> 00:31:25,766 ON THE SURFACE OF MARS IS QUITE LOW. 748 00:31:25,766 --> 00:31:27,566 AND THESE THINGS HERE, BY THE WAY, 749 00:31:27,566 --> 00:31:29,033 THE NOTION OF THIS ONE 750 00:31:29,033 --> 00:31:32,100 WAS THAT IT WOULDN'T TRANSPORT HYDROGEN TO MARS. 751 00:31:32,100 --> 00:31:34,466 IT WOULD TRANSPORT HYDROCARBON FUEL 752 00:31:34,466 --> 00:31:35,933 AND JUST MAKE THE OXYGEN, 753 00:31:35,933 --> 00:31:39,066 WHICH IS 3/4 OF THE PROPELLANT, 754 00:31:39,066 --> 00:31:42,833 BECAUSE THE SMALLER SIZE MAKES IT HARDER TO TRANSPORT HYDROGEN. 755 00:31:42,833 --> 00:31:48,600 NOW, THIS MISSION... 756 00:31:48,600 --> 00:31:51,433 IS DESIGNED IN ACCORDANCE WITH, YOU KNOW, 757 00:31:51,433 --> 00:31:55,066 JUST THREE FALCON HEAVY LAUNCHES PER OPPORTUNITY. 758 00:31:55,066 --> 00:31:57,633 SLS, IN ITS EARLIEST INCARNATION, 759 00:31:57,633 --> 00:31:59,400 IS 75 TONS TO ORBIT. 760 00:31:59,400 --> 00:32:02,433 THAT WOULD INCREASE THE MASS MARGINS BY 50%. 761 00:32:02,433 --> 00:32:05,266 OR YOU COULD SAY, OKAY, WE'LL DO TWO FALCON HEAVIES 762 00:32:05,266 --> 00:32:07,000 FOR EACH OF THESE THREE PACKAGES, 763 00:32:07,000 --> 00:32:10,300 MATE AND DOCK, AND THAT WOULD DOUBLE IT. 764 00:32:10,300 --> 00:32:13,300 WHAT I AM SAYING HERE 765 00:32:13,300 --> 00:32:17,333 IS NOT TO ADVOCATE THIS DESIGN IN DETAIL, 766 00:32:17,333 --> 00:32:21,033 BUT TO SAY, IF YOU WANT TO GET TO MARS, 767 00:32:21,033 --> 00:32:23,433 YOU WANT TO TRY TO APPROACH IT 768 00:32:23,433 --> 00:32:26,700 IN A SPIRIT OF RUTHLESS MINIMALISM, 769 00:32:26,700 --> 00:32:29,466 TO SAY, "HOW COULD WE ACTUALLY DO THIS WITH WHAT WE HAVE 770 00:32:29,466 --> 00:32:31,033 OR WHAT WE'RE LIKELY TO HAVE?" 771 00:32:31,033 --> 00:32:32,333 AS OPPOSED TO SAYING, 772 00:32:32,333 --> 00:32:34,533 "WELL, YOU KNOW, WHEN I GO TO MARS, 773 00:32:34,533 --> 00:32:37,033 "I WANT TO HAVE THIS NAUTILUS SPACESHIP 774 00:32:37,033 --> 00:32:41,333 "WITH A, YOU KNOW, SPA AND A SAUNA AND THIS AND THAT, 775 00:32:41,333 --> 00:32:44,933 "AND A POOL ROOM, BECAUSE REALLY, WITHOUT A POOL ROOM, 776 00:32:44,933 --> 00:32:48,900 ASTRONAUTS WON'T BE HAPPY." 777 00:32:48,900 --> 00:32:52,600 YOU WANT TO SAY, "HOW CAN WE ACTUALLY GET THIS DONE 778 00:32:52,600 --> 00:32:53,900 "WITH THE SORT OF THING WE HAVE 779 00:32:53,900 --> 00:32:57,233 AND DESIGN THE MISSION IN THAT WAY?" 780 00:32:57,233 --> 00:32:58,500 BUT THE BOTTOM LINE IS, 781 00:32:58,500 --> 00:33:01,933 WHETHER WE DO IT WITH A TRUE HEAVY-LIFT BOOSTER 782 00:33:01,933 --> 00:33:03,400 LIKE "MARS DIRECT" IS, 783 00:33:03,400 --> 00:33:08,600 OR WE DO IT IN THIS SORT OF-- THIS FALCON DIRECT ARCHITECTURE 784 00:33:08,600 --> 00:33:10,733 WITH A SEMI-HEAVY BOOSTER, 785 00:33:10,733 --> 00:33:11,866 THERE'S WAYS TO DO THIS. 786 00:33:11,866 --> 00:33:14,300 WE DO NOT NEED SCIENCE-FICTION SPACESHIPS 787 00:33:14,300 --> 00:33:16,400 TO GO TO MARS, OKAY? 788 00:33:16,400 --> 00:33:17,566 WE JUST DON'T. 789 00:33:17,566 --> 00:33:20,533 SO, OKAY. 790 00:33:25,933 --> 00:33:27,033 I'LL LEAVE IT THERE. 791 00:33:27,033 --> 00:33:28,466 THANKS. 792 00:33:28,466 --> 00:33:32,000 [applause] 793 00:33:38,700 --> 00:33:40,333 - SO WE HAVE TIME FOR QUESTIONS. 794 00:33:40,333 --> 00:33:41,666 WAIT FOR THE MICROPHONE, 795 00:33:41,666 --> 00:33:44,166 AND PLEASE STAND UP WHEN YOU ASK A QUESTION. 796 00:33:46,966 --> 00:33:50,800 - SO, NASA LEADERSHIP NOW SEEMS TO EMBRACE MARS 797 00:33:50,800 --> 00:33:54,500 AS THE PRIMARY DESTINATION. 798 00:33:54,500 --> 00:33:59,266 AND THEY CERTAINLY ARE AWARE OF YOUR PLAN. 799 00:33:59,266 --> 00:34:01,433 SO, WHAT IS THEIR RESPONSE? 800 00:34:01,433 --> 00:34:04,800 WHY WOULD NOT THEY GET INTERESTED IN THIS PLAN 801 00:34:04,800 --> 00:34:06,633 AND TRYING TO ADOPT IT? 802 00:34:06,633 --> 00:34:08,866 BECAUSE IT'S SO MUCH CHEAPER, IT SEEMS TO ME. 803 00:34:08,866 --> 00:34:10,300 NOT ONLY FASTER, BUT CHEAPER. 804 00:34:10,300 --> 00:34:15,533 - OKAY, WELL, I UNDERSTAND WHY YOU JUST SAID WHAT YOU SAID, 805 00:34:15,533 --> 00:34:17,266 BUT I DISAGREE WITH YOUR PREMISE 806 00:34:17,266 --> 00:34:21,066 THAT NASA HAS EMBRACED MARS AS A DESTINATION. 807 00:34:21,066 --> 00:34:24,933 IF NASA HAD EMBRACED MARS AS A DESTINATION, 808 00:34:24,933 --> 00:34:28,166 IT WOULDN'T BE PLANNING AN ASTEROID-REDIRECT MISSION, 809 00:34:28,166 --> 00:34:30,900 BECAUSE THE ASTEROID-REDIRECT MISSION HAS NOTHING TO DO 810 00:34:30,900 --> 00:34:32,700 WITH HUMANS TO MARS. 811 00:34:32,700 --> 00:34:39,033 OKAY, THE--THEY'VE CHOSEN TO INVOKE HUMANS TO MARS 812 00:34:39,033 --> 00:34:42,066 AS SIZZLE BUT NOT THE STEAK, OKAY? 813 00:34:42,066 --> 00:34:44,033 IN OTHER WORDS-- 814 00:34:44,033 --> 00:34:47,766 AND THIS IS FUNDAMENTAL. 815 00:34:50,433 --> 00:34:54,733 YOU CAN'T GET TO MARS WITH A PROGRAM 816 00:34:54,733 --> 00:34:59,766 THAT IS DESIGNED AROUND PLEASING VARIOUS CONSTITUENCIES 817 00:34:59,766 --> 00:35:01,166 WITHIN THE ORGANIZATION. 818 00:35:01,166 --> 00:35:02,833 FOR INSTANCE, THE ASTEROID-REDIRECT MISSION, 819 00:35:02,833 --> 00:35:05,766 THE PURPOSE OF IT IS TO PROVIDE A MISSION 820 00:35:05,766 --> 00:35:08,266 FOR AN ELECTRIC PROPULSION SYSTEM 821 00:35:08,266 --> 00:35:11,766 WHICH HAPPENS TO HAVE THE EAR OF THE CURRENT ADMINISTRATOR. 822 00:35:11,766 --> 00:35:13,533 OKAY, IT IS-- 823 00:35:13,533 --> 00:35:15,100 NO ONE IN THEIR WILDEST DREAMS 824 00:35:15,100 --> 00:35:18,300 EVER PUT REDIRECTING A 500-TON BOULDER 825 00:35:18,300 --> 00:35:19,800 FROM THE NEAR-EARTH ASTEROID BELT 826 00:35:19,800 --> 00:35:21,366 INTO A RETROGRADE LUNAR ORBIT 827 00:35:21,366 --> 00:35:23,700 ON THE CRITICAL PATH TO MARS. 828 00:35:23,700 --> 00:35:26,966 OKAY, I MEAN, YOU KNOW, 829 00:35:26,966 --> 00:35:29,133 THIS IS NEW. 830 00:35:29,133 --> 00:35:33,200 AND THE--NOW, SOME PEOPLE HAVE ARGUED THAT A LUNAR BASE 831 00:35:33,200 --> 00:35:35,033 IS ON THE CRITICAL PATH TO MARS, 832 00:35:35,033 --> 00:35:36,533 AND I DISAGREE, 833 00:35:36,533 --> 00:35:39,633 BUT AT LEAST THEIR ARGUMENT HAS THE MERIT 834 00:35:39,633 --> 00:35:41,533 THAT A LUNAR BASE IS ON THE CRITICAL PATH 835 00:35:41,533 --> 00:35:44,033 TO HAVING A LUNAR BASE. 836 00:35:44,033 --> 00:35:46,400 AND SO, IF YOU BUILD A LUNAR BASE, 837 00:35:46,400 --> 00:35:48,100 YOU WILL AT LEAST GET A LUNAR BASE. 838 00:35:48,100 --> 00:35:52,100 OKAY, SO, YOU CAN BE SANE AND ARGUE THAT. 839 00:35:52,100 --> 00:35:56,333 BUT THE-- 840 00:35:56,333 --> 00:35:57,900 BECAUSE, IN FACT, THE PEOPLE WHO ARGUE 841 00:35:57,900 --> 00:35:59,766 THAT WE NEED TO BUILD THE LUNAR BASE BEFORE WE GO TO MARS 842 00:35:59,766 --> 00:36:01,900 ARE PEOPLE WHO WANT TO HAVE A LUNAR BASE. 843 00:36:01,900 --> 00:36:04,100 NOW, THE-- 844 00:36:08,966 --> 00:36:12,366 THE PROBLEM HERE IS, IT'S ENTROPY.