1 00:00:04,400 --> 00:00:07,800 Speaker 1: Welcome to tech Stuff, a production from My Heart Radio. 2 00:00:11,800 --> 00:00:14,040 Speaker 1: Hey there, and welcome to tech Stuff. I'm your host, 3 00:00:14,120 --> 00:00:17,000 Speaker 1: Jonathan Strickland. I'm an executive producer with my Heart Radio 4 00:00:17,079 --> 00:00:20,599 Speaker 1: and how the Tech Area. It is time for a 5 00:00:20,720 --> 00:00:24,400 Speaker 1: tech Stuff classic episode. This episode originally published back on 6 00:00:24,520 --> 00:00:31,040 Speaker 1: December nine, two thousand fifteen. It is titled how Satellites Work. Enjoy. 7 00:00:32,440 --> 00:00:35,800 Speaker 1: Let's talk about satellites and what they are. So satellite 8 00:00:35,840 --> 00:00:39,760 Speaker 1: is something that's in orbit around another object. And of 9 00:00:39,800 --> 00:00:42,880 Speaker 1: course Earth has had a satellite for billions of years. 10 00:00:42,960 --> 00:00:46,080 Speaker 1: That would be the Moon. That's a natural satellite. But 11 00:00:46,120 --> 00:00:48,839 Speaker 1: if we want to look at man made satellites, we 12 00:00:48,920 --> 00:00:51,720 Speaker 1: have to go back a few decades. And in fact, 13 00:00:51,800 --> 00:00:57,440 Speaker 1: the foundation for man made satellites, the principles, the idea 14 00:00:57,640 --> 00:01:01,160 Speaker 1: of what would be required go act well before the 15 00:01:01,160 --> 00:01:05,440 Speaker 1: space race ever started. That would be Isaac Newton who 16 00:01:05,480 --> 00:01:07,840 Speaker 1: came up with the idea of what would be required 17 00:01:07,840 --> 00:01:10,600 Speaker 1: to create a satellite. Now that's not what he necessarily 18 00:01:10,640 --> 00:01:13,440 Speaker 1: called it, but this was published in a famous thought 19 00:01:13,480 --> 00:01:18,800 Speaker 1: experiment back in seventeen twenty nine, and at the time 20 00:01:18,840 --> 00:01:23,160 Speaker 1: he was really concentrating on gravity, which is pretty heavy stuff. 21 00:01:23,640 --> 00:01:27,880 Speaker 1: So Newton's thought experiment was famous. People have talked about 22 00:01:27,920 --> 00:01:30,880 Speaker 1: this a lot. You've probably heard about it. He said, 23 00:01:30,880 --> 00:01:32,880 Speaker 1: what if you were to go at the top of 24 00:01:32,920 --> 00:01:36,600 Speaker 1: a really really tall mountain and you build a cannon 25 00:01:36,880 --> 00:01:39,640 Speaker 1: on the top of that mountain, and you aim that 26 00:01:39,800 --> 00:01:44,320 Speaker 1: cannon so that the barrel is parallel with the earth 27 00:01:44,400 --> 00:01:47,880 Speaker 1: below you, so it's at at the same you know, 28 00:01:48,080 --> 00:01:52,960 Speaker 1: same angle as the ground down at the base of 29 00:01:52,960 --> 00:01:57,160 Speaker 1: the mountain. You fire the cannon, the cannon ball flies 30 00:01:57,200 --> 00:02:00,920 Speaker 1: out and it moves away from the cannon, and but 31 00:02:00,960 --> 00:02:04,040 Speaker 1: it also starts to fall because gravity has been pulling 32 00:02:04,040 --> 00:02:06,360 Speaker 1: on the cannonball the whole time. You know, gravity was 33 00:02:06,400 --> 00:02:08,240 Speaker 1: pulling on the cannonball when it was in the cannon. 34 00:02:08,440 --> 00:02:10,680 Speaker 1: It's pulling on the cannonball now that it's emerged from 35 00:02:10,720 --> 00:02:13,560 Speaker 1: the cannon. Eventually, this cannonball is going to fall to 36 00:02:13,600 --> 00:02:17,120 Speaker 1: the ground. And by eventually, it's it's based upon the 37 00:02:17,160 --> 00:02:20,800 Speaker 1: altitude that the cannonball already is at. Uh doesn't have 38 00:02:20,800 --> 00:02:23,760 Speaker 1: anything to do with the forward velocity so much as 39 00:02:23,840 --> 00:02:27,560 Speaker 1: the altitude. He said, well, what if you were to 40 00:02:27,560 --> 00:02:30,240 Speaker 1: to pack more gunpowder in this cannon and you fire it, 41 00:02:30,320 --> 00:02:32,640 Speaker 1: might it will go further because it's moving out a 42 00:02:32,639 --> 00:02:36,240 Speaker 1: forward velocity. That's that's greater than the previous one, but 43 00:02:36,320 --> 00:02:40,520 Speaker 1: it still will eventually fall to the earth. Uh really 44 00:02:40,520 --> 00:02:42,320 Speaker 1: in that same amount of time. It's just gonna be 45 00:02:42,360 --> 00:02:45,400 Speaker 1: further out from their first shot. But then you keep 46 00:02:45,400 --> 00:02:48,919 Speaker 1: packing more and more gunpowder in, and eventually you pack 47 00:02:49,040 --> 00:02:51,640 Speaker 1: enough gunpowder in so that when you fire the cannonball, 48 00:02:52,480 --> 00:02:55,799 Speaker 1: it is flying out at a forward velocity at a 49 00:02:55,800 --> 00:02:59,040 Speaker 1: at a rate that is equal to how the Earth 50 00:02:59,200 --> 00:03:03,000 Speaker 1: is curving a way from the cannonball. So, in other words, 51 00:03:03,480 --> 00:03:06,320 Speaker 1: the canniballs falling toward the Earth, but the Earth is 52 00:03:06,320 --> 00:03:09,200 Speaker 1: curving away from the cannonball at that same rate, so 53 00:03:09,240 --> 00:03:13,400 Speaker 1: the cannibal never falls down to hit the Earth's surface 54 00:03:13,800 --> 00:03:16,400 Speaker 1: because the Earth is falling away from the cannonball at 55 00:03:16,440 --> 00:03:19,320 Speaker 1: the same rate that the cannonball itself is falling. This 56 00:03:19,320 --> 00:03:22,080 Speaker 1: would mean that eventually you would shoot yourself in the back, 57 00:03:22,960 --> 00:03:25,480 Speaker 1: because the cannonball would make a full rotation around the 58 00:03:25,520 --> 00:03:28,440 Speaker 1: Earth and come back to its point of origin. At least, 59 00:03:28,440 --> 00:03:31,480 Speaker 1: that was the thought experiment that Newton had proposed, which 60 00:03:31,520 --> 00:03:34,120 Speaker 1: seemed like a really clever idea, but there was no 61 00:03:34,200 --> 00:03:36,880 Speaker 1: practical means of testing it or putting it to any 62 00:03:37,000 --> 00:03:41,040 Speaker 1: use back in Newton's day, it was just an interesting idea. 63 00:03:41,360 --> 00:03:46,280 Speaker 1: It would not be until October four, nineteen seven, and 64 00:03:46,320 --> 00:03:50,040 Speaker 1: that's when the then Soviet Union made history by launching 65 00:03:50,080 --> 00:03:52,960 Speaker 1: the first man made satellite into Earth orbit, and that 66 00:03:53,040 --> 00:03:57,800 Speaker 1: satellite was the spot Nick one. But it was fairly simple. 67 00:03:58,680 --> 00:04:01,840 Speaker 1: It was a ball all that was silver in color. 68 00:04:01,960 --> 00:04:05,360 Speaker 1: It was about twenty two point eight inches in diameter, 69 00:04:05,400 --> 00:04:08,000 Speaker 1: which is around fifty eight centimeters, so not very big, 70 00:04:08,320 --> 00:04:11,200 Speaker 1: and it weighed a hundred eighty three point nine pounds 71 00:04:11,400 --> 00:04:15,040 Speaker 1: or eighty three point six ms. The body was made 72 00:04:15,080 --> 00:04:18,560 Speaker 1: out of an aluminum alloy, and the shell of that 73 00:04:18,600 --> 00:04:22,880 Speaker 1: aluminum was just two millimeters thick. It was actually two 74 00:04:22,920 --> 00:04:26,599 Speaker 1: hemispheres of a globe that were connected together by thirty 75 00:04:26,680 --> 00:04:32,680 Speaker 1: six bolts around the circumference of those hemispheres. It had 76 00:04:32,960 --> 00:04:37,320 Speaker 1: two antennas, and each antenna had two beams, so like 77 00:04:37,400 --> 00:04:43,000 Speaker 1: four prongs extending backward from the scent from the sphere itself, 78 00:04:43,040 --> 00:04:46,440 Speaker 1: almost like it had four legs. One pair of antenna 79 00:04:46,440 --> 00:04:49,160 Speaker 1: where seven point nine feet long or about two point 80 00:04:49,200 --> 00:04:52,080 Speaker 1: four meters. The other pair was twelve point eight feet 81 00:04:52,120 --> 00:04:56,920 Speaker 1: long or three point nine meters. Inside the satellite. There 82 00:04:56,960 --> 00:04:59,960 Speaker 1: wasn't a whole lot, not compared to what had originally 83 00:05:00,080 --> 00:05:03,880 Speaker 1: been planned to put in the satellite. Inside it was 84 00:05:03,920 --> 00:05:07,320 Speaker 1: a radio transmitter so it could communicate back to Earth, 85 00:05:07,880 --> 00:05:12,080 Speaker 1: had three silver zinc batteries that would provide power. It 86 00:05:12,120 --> 00:05:15,960 Speaker 1: had a couple of different switches inside of it, remote switches, 87 00:05:16,520 --> 00:05:20,200 Speaker 1: a thermal system fan was in there, a controlled thermal switch, 88 00:05:20,240 --> 00:05:22,919 Speaker 1: and a barrel metric switch. We're in there. So and 89 00:05:22,920 --> 00:05:27,080 Speaker 1: it was also filled with nitrogen gas to create internal pressure. Essentially, 90 00:05:27,839 --> 00:05:30,840 Speaker 1: the only things this this was really the only thing 91 00:05:30,880 --> 00:05:34,479 Speaker 1: this this um satellite could do was monitor its own 92 00:05:34,640 --> 00:05:37,720 Speaker 1: systems like how hot was it or cold was it? 93 00:05:37,800 --> 00:05:40,599 Speaker 1: What was the pressure like, and then it would beam 94 00:05:40,680 --> 00:05:44,240 Speaker 1: down information in a series of beeps. In fact, my 95 00:05:44,680 --> 00:05:47,960 Speaker 1: former co host Chris Palette used to refer to spot 96 00:05:48,040 --> 00:05:52,320 Speaker 1: Nick as the thing what beeps. It actually sounded a 97 00:05:52,360 --> 00:05:59,240 Speaker 1: bit like this. So if you had had a Ham 98 00:05:59,320 --> 00:06:03,960 Speaker 1: radio back in nine and you were tuning in, you 99 00:06:04,000 --> 00:06:07,080 Speaker 1: could actually pick up that signal as sput Nick passed 100 00:06:07,320 --> 00:06:10,919 Speaker 1: overhead because it was broadcasting on a frequency that was 101 00:06:10,960 --> 00:06:14,680 Speaker 1: within the citizen band radio frequency, and that meant that 102 00:06:14,720 --> 00:06:18,520 Speaker 1: people could actually listen in as sput Nick went overhead. 103 00:06:18,560 --> 00:06:21,159 Speaker 1: It only took ninety eight minutes for the satellite to 104 00:06:21,160 --> 00:06:24,119 Speaker 1: go around the Earth, so every hour and a half 105 00:06:24,200 --> 00:06:26,280 Speaker 1: or so you would be able to pick this up. 106 00:06:26,800 --> 00:06:32,000 Speaker 1: And it freaked people out, particularly in the United States. 107 00:06:32,040 --> 00:06:34,839 Speaker 1: People were freaking out because they were able to actually 108 00:06:35,360 --> 00:06:38,719 Speaker 1: hear evidence of the Soviet Union's ability to send an 109 00:06:38,720 --> 00:06:42,840 Speaker 1: object into space. And if they could do that, there 110 00:06:42,920 --> 00:06:45,080 Speaker 1: was also the fear that they could perhaps fire a 111 00:06:45,120 --> 00:06:48,919 Speaker 1: ballistic missile, maybe with a nuclear warhead, at the United 112 00:06:48,960 --> 00:06:52,359 Speaker 1: States that they had had now had the capability to 113 00:06:52,560 --> 00:06:58,760 Speaker 1: fire massive destructive weapons at the US from a world away, 114 00:06:59,160 --> 00:07:02,280 Speaker 1: and at this time the Cold War was going on strong. 115 00:07:03,000 --> 00:07:06,560 Speaker 1: So it caused more than a little stir. It was 116 00:07:06,680 --> 00:07:11,240 Speaker 1: the fuel for tons of different science fiction films. Uh, 117 00:07:11,280 --> 00:07:15,400 Speaker 1: They're all these different U instructional movies that explained what 118 00:07:15,480 --> 00:07:18,080 Speaker 1: you need to do in the case of a nuclear war, 119 00:07:19,360 --> 00:07:23,920 Speaker 1: and most of them were freakishly optimistic. At any rate, 120 00:07:24,400 --> 00:07:27,760 Speaker 1: it propelled the United States into a new era of 121 00:07:27,960 --> 00:07:31,000 Speaker 1: research and development. The US had already been planning on 122 00:07:31,080 --> 00:07:35,040 Speaker 1: getting into the space race, but this meant that suddenly 123 00:07:35,080 --> 00:07:39,040 Speaker 1: everything was cranked up to eleven, as spinal tap would say. 124 00:07:39,120 --> 00:07:43,960 Speaker 1: So it really literally launched the space race between the 125 00:07:44,040 --> 00:07:47,960 Speaker 1: United States and the Soviet Union. Now, for the story 126 00:07:47,960 --> 00:07:50,239 Speaker 1: of spot Nick itself, you actually have to go back 127 00:07:50,720 --> 00:07:55,080 Speaker 1: much further back to the nineteen forties in fact, or 128 00:07:55,080 --> 00:07:59,280 Speaker 1: even earlier, when you're looking at the the rocket program 129 00:07:59,280 --> 00:08:03,240 Speaker 1: out of the Soviet Union during World War Two. So 130 00:08:04,320 --> 00:08:07,840 Speaker 1: officially you would argue that nineteen fifty two was was 131 00:08:07,880 --> 00:08:12,600 Speaker 1: what got Sputnik itself going. Within the Soviet Union, that's 132 00:08:12,640 --> 00:08:16,320 Speaker 1: what an organization called the International Council of Scientific Unions 133 00:08:16,840 --> 00:08:20,200 Speaker 1: called for artificial satellites to be launched in order to 134 00:08:20,240 --> 00:08:23,000 Speaker 1: study solar activity, which was going to be reaching a 135 00:08:23,120 --> 00:08:27,920 Speaker 1: peak in nineteen fifty eight, and the United States started 136 00:08:28,000 --> 00:08:31,080 Speaker 1: planning a launch at least as far back as nineteen 137 00:08:31,120 --> 00:08:35,480 Speaker 1: fifty five, and their project was called Vanguard, and pretty 138 00:08:35,559 --> 00:08:38,120 Speaker 1: much the world was looking at the United States as 139 00:08:38,160 --> 00:08:40,480 Speaker 1: the leader. It was going to be the US that 140 00:08:40,480 --> 00:08:45,040 Speaker 1: would be launching a satellite sometime around the summer of 141 00:08:45,080 --> 00:08:48,840 Speaker 1: nineteen fifty seven. But the Soviet Union thought, hey, we 142 00:08:48,960 --> 00:08:51,760 Speaker 1: have the opportunity to show up our rival, and so 143 00:08:51,840 --> 00:08:55,400 Speaker 1: they really put Sputnik on the fast track now to 144 00:08:55,400 --> 00:08:57,760 Speaker 1: to look at what was going on in the Soviet Union. 145 00:08:58,160 --> 00:09:01,920 Speaker 1: Going back to the nineties, there was a man named 146 00:09:02,000 --> 00:09:06,400 Speaker 1: Mikhail tiken Revov. I'm gonna mess up that name all 147 00:09:06,400 --> 00:09:09,920 Speaker 1: the time. Tick Hanravov who led a team of scientists 148 00:09:09,960 --> 00:09:13,480 Speaker 1: to design, build, and launch spot Nick one. But their 149 00:09:13,559 --> 00:09:17,520 Speaker 1: early work was really looking at missile systems, ballistic missile 150 00:09:17,600 --> 00:09:21,840 Speaker 1: missile systems for military use. Uh, they just saw the 151 00:09:21,920 --> 00:09:25,959 Speaker 1: potential for using those same systems to launch satellite into space. 152 00:09:26,600 --> 00:09:28,880 Speaker 1: And they were really looking at the possibility of using 153 00:09:28,960 --> 00:09:31,280 Speaker 1: multi stage rockets in order to get the right amount 154 00:09:31,280 --> 00:09:36,280 Speaker 1: of acceleration to push an object into orbit. And they 155 00:09:36,280 --> 00:09:39,720 Speaker 1: were often relying on research performed not just by their team, 156 00:09:39,760 --> 00:09:43,280 Speaker 1: but by other scientific teams around the world. Often this 157 00:09:43,360 --> 00:09:46,920 Speaker 1: was information that we're that was pulled in through espionage. 158 00:09:47,000 --> 00:09:51,400 Speaker 1: It wasn't necessarily the scientific community openly sharing this information. 159 00:09:51,920 --> 00:09:55,439 Speaker 1: And originally, uh, they were really looking at how can 160 00:09:55,480 --> 00:09:59,280 Speaker 1: we make missiles better missiles for the Soviet Union. The 161 00:09:59,280 --> 00:10:02,440 Speaker 1: group would form in nineteen forty six, so not long 162 00:10:02,480 --> 00:10:05,800 Speaker 1: after the end of World War Two, and the team 163 00:10:05,840 --> 00:10:09,560 Speaker 1: worked on satellite plans pretty much in secret because they 164 00:10:09,559 --> 00:10:12,400 Speaker 1: weren't sure if the Soviet government would actually appreciate their 165 00:10:12,440 --> 00:10:15,720 Speaker 1: interest in scientific research that did not have an immediate 166 00:10:15,840 --> 00:10:22,200 Speaker 1: military application. Now, keep in mind that until nineteen fifty three, 167 00:10:22,400 --> 00:10:25,959 Speaker 1: the Soviet Union was being led by Joseph Stalin, and 168 00:10:27,080 --> 00:10:34,240 Speaker 1: he was an incredibly brutal dictator, and paranoia was rampant 169 00:10:34,440 --> 00:10:37,520 Speaker 1: in the Soviet Union. There were stories about secret police 170 00:10:37,600 --> 00:10:40,280 Speaker 1: and kidnappings in the middle of the night. People lived 171 00:10:40,280 --> 00:10:44,400 Speaker 1: in constant fear of being arrested or executed. But after 172 00:10:44,480 --> 00:10:49,000 Speaker 1: Stalin died in March ninette, people were able to concentrate 173 00:10:49,080 --> 00:10:52,960 Speaker 1: on something beyond just not being noticed. It's hard to 174 00:10:53,000 --> 00:10:56,439 Speaker 1: imagine how terrifying that time must have been, but it's 175 00:10:56,480 --> 00:11:00,880 Speaker 1: probably no coincidence that it was nineteen fifty for when 176 00:11:00,920 --> 00:11:04,839 Speaker 1: the Soviet scientists stopped hiding the fact that they were 177 00:11:04,880 --> 00:11:08,280 Speaker 1: performing this satellite research. They would talk about it openly, 178 00:11:08,840 --> 00:11:12,680 Speaker 1: and the project received support from various scientific societies within 179 00:11:12,760 --> 00:11:16,200 Speaker 1: the USSR, but it wouldn't be until nineteen fifty six 180 00:11:16,200 --> 00:11:20,640 Speaker 1: that they received official approval from the Kremlin. So if 181 00:11:20,640 --> 00:11:26,320 Speaker 1: you want to hear a really amazing story about bureaucracy, science, politics, 182 00:11:26,400 --> 00:11:29,400 Speaker 1: and how messed up everything was in the Soviet Union 183 00:11:29,400 --> 00:11:33,920 Speaker 1: in the nineteen fifties, you should really research the full 184 00:11:33,960 --> 00:11:38,880 Speaker 1: story of spot Nik because it's amazing that this project 185 00:11:39,000 --> 00:11:43,439 Speaker 1: ever really got a lot of of support. In large 186 00:11:43,480 --> 00:11:46,160 Speaker 1: part the support was coming from the Soviet Union wanting 187 00:11:46,200 --> 00:11:51,200 Speaker 1: to demonstrate its power, not to pursue science, but in 188 00:11:51,320 --> 00:11:54,640 Speaker 1: order to show the rest of the world we're the 189 00:11:54,679 --> 00:11:58,400 Speaker 1: big bear, don't mess with us. There were a whole 190 00:11:58,400 --> 00:12:01,640 Speaker 1: bunch of different departments. It all worked on the design 191 00:12:01,760 --> 00:12:05,720 Speaker 1: of the spot Nick project, and it's kind of interesting 192 00:12:05,720 --> 00:12:09,480 Speaker 1: to see how diverse this group was. So those those 193 00:12:09,480 --> 00:12:13,440 Speaker 1: different departments included the Academy of Sciences of USSR, which 194 00:12:13,679 --> 00:12:17,840 Speaker 1: oversaw the scientific research and development of the project. There 195 00:12:17,920 --> 00:12:22,320 Speaker 1: was the organization Okay b DASH one, which was the 196 00:12:22,440 --> 00:12:26,840 Speaker 1: u s s R Experimental Design Bureau. It's essentially was 197 00:12:26,920 --> 00:12:30,680 Speaker 1: the equivalent of our DARPA here in the United States. 198 00:12:30,679 --> 00:12:34,679 Speaker 1: It was a research and development program that really took 199 00:12:34,760 --> 00:12:37,520 Speaker 1: big risks to see if they could find big reward 200 00:12:37,960 --> 00:12:43,560 Speaker 1: from scientific research implemented in practical ways. That particularly, that 201 00:12:43,640 --> 00:12:46,320 Speaker 1: particular department fell under the direction of the Ministry of 202 00:12:46,400 --> 00:12:51,199 Speaker 1: Defense Industry. So that group was responsible for designing the 203 00:12:51,280 --> 00:12:55,719 Speaker 1: body of the satellite, and in the Satellite biz we 204 00:12:55,760 --> 00:12:59,880 Speaker 1: referred to this as the bus. The bus is essentially 205 00:13:00,480 --> 00:13:04,080 Speaker 1: the the body or shell inside which all the instrumentation 206 00:13:04,160 --> 00:13:08,120 Speaker 1: exists apart from you know, some instrumentation obviously has to 207 00:13:08,120 --> 00:13:09,880 Speaker 1: be on the outside of the bus, like any sort 208 00:13:09,880 --> 00:13:14,040 Speaker 1: of imagery or antenna, but you get what I mean. Next, 209 00:13:14,080 --> 00:13:17,200 Speaker 1: we have the Ministry of Radio Industry. They were in 210 00:13:17,280 --> 00:13:22,400 Speaker 1: charge of flight control systems, radio and telemetry systems. Then 211 00:13:22,440 --> 00:13:25,960 Speaker 1: you had the Ministry of ship Building. The ship Building 212 00:13:26,000 --> 00:13:29,400 Speaker 1: Ministry was responsible for designing the gyroscopes that would go 213 00:13:29,440 --> 00:13:32,840 Speaker 1: in the satellite. You had the Ministry of Machine Building. 214 00:13:33,400 --> 00:13:37,840 Speaker 1: They were responsible for ground processing, transport, fueling, and launch hardware. 215 00:13:38,559 --> 00:13:40,679 Speaker 1: You had the Ministry of Defense itself which was in 216 00:13:40,760 --> 00:13:44,679 Speaker 1: charge of launch operations. You had the Ministry of Avia 217 00:13:44,880 --> 00:13:49,360 Speaker 1: Aviation Industry which was in charge of the tracking systems, 218 00:13:49,640 --> 00:13:52,920 Speaker 1: and the Special Committee of the Soviet of Ministers, which 219 00:13:52,960 --> 00:13:57,319 Speaker 1: were all about the management and coordination of the program overall. Now, 220 00:13:57,320 --> 00:14:01,959 Speaker 1: originally spot NICK was referred to as Object D and 221 00:14:02,040 --> 00:14:04,720 Speaker 1: it was supposed to be a much larger, much more 222 00:14:04,800 --> 00:14:09,079 Speaker 1: sophisticated satellite. It was not supposed to just be the 223 00:14:09,080 --> 00:14:11,520 Speaker 1: thing what beeps. It was supposed to have a lot 224 00:14:11,559 --> 00:14:15,640 Speaker 1: of instrumentation for actual scientific study, with a collection of 225 00:14:15,720 --> 00:14:20,120 Speaker 1: useful instruments but the projects suffered several setbacks in the 226 00:14:20,160 --> 00:14:24,000 Speaker 1: design process that kept pushing back when they would be 227 00:14:24,040 --> 00:14:27,760 Speaker 1: able to launch, and there was a growing concern that 228 00:14:27,800 --> 00:14:29,760 Speaker 1: the United States was going to be able to launch 229 00:14:29,760 --> 00:14:33,640 Speaker 1: a satellite in orbit starting on July first nine. So 230 00:14:33,680 --> 00:14:36,320 Speaker 1: they had a new goal. They wanted to strip down 231 00:14:36,440 --> 00:14:39,360 Speaker 1: their ideas to just the most essential elements to try 232 00:14:39,400 --> 00:14:43,520 Speaker 1: and beat America to the punch, and they did. They 233 00:14:43,560 --> 00:14:48,920 Speaker 1: were able to create a much smaller, more basic satellite 234 00:14:49,040 --> 00:14:50,720 Speaker 1: and they were able to launch it before the United 235 00:14:50,760 --> 00:14:54,600 Speaker 1: States could send their own satellite into space, and they 236 00:14:54,600 --> 00:14:57,680 Speaker 1: set a precedent, and in fact, only did the USSR 237 00:14:57,760 --> 00:15:01,600 Speaker 1: beat the USA, they did it twice. We'll be back 238 00:15:01,640 --> 00:15:04,280 Speaker 1: with more of this classic episode about how satellites work 239 00:15:04,560 --> 00:15:17,400 Speaker 1: after this quick break. The second satellite, which was Sputnik two, 240 00:15:17,920 --> 00:15:21,400 Speaker 1: contained the first life form sent into Earth orbit, and 241 00:15:21,480 --> 00:15:26,160 Speaker 1: that was the dog named Lyca, and Likeca, was always 242 00:15:26,240 --> 00:15:30,480 Speaker 1: destined to die during this mission. There was no plan 243 00:15:30,800 --> 00:15:35,760 Speaker 1: for Lyca to return to Earth safely. Uhlica was going 244 00:15:35,840 --> 00:15:40,960 Speaker 1: to die inside the satellite, either by starvation or thirst. 245 00:15:42,360 --> 00:15:44,600 Speaker 1: It was just no or suffocation that was just known 246 00:15:44,640 --> 00:15:47,520 Speaker 1: that this was a one way trip for the dog. Um, 247 00:15:47,560 --> 00:15:50,800 Speaker 1: the dog likely died due to overheating fairly early in 248 00:15:50,840 --> 00:15:55,080 Speaker 1: the mission based upon what the instrumentation was saying. And 249 00:15:55,080 --> 00:15:57,960 Speaker 1: there have been a lot of web comics, cartoons and 250 00:15:58,160 --> 00:16:00,760 Speaker 1: an amazing song. More than one song, but there's a 251 00:16:00,800 --> 00:16:04,360 Speaker 1: great song called Space Doggedy which was written by Jonathan 252 00:16:04,400 --> 00:16:08,400 Speaker 1: Colton and obviously has uh a lot of influence from 253 00:16:08,440 --> 00:16:12,040 Speaker 1: Space Oddity from David Bowie Space Oddity in there. Space 254 00:16:12,080 --> 00:16:15,240 Speaker 1: Doggy great song. There's actually a video on YouTube someone's 255 00:16:15,240 --> 00:16:18,600 Speaker 1: put together with actual footage of like a from spot 256 00:16:18,720 --> 00:16:22,640 Speaker 1: Nick two. And that's all I'm going to say about that, 257 00:16:22,800 --> 00:16:26,480 Speaker 1: because otherwise I'm gonna get all choked up because to me, 258 00:16:26,520 --> 00:16:29,120 Speaker 1: it's a very sad story and necessary story. I totally 259 00:16:29,200 --> 00:16:34,000 Speaker 1: understand why we need to use animals to test the systems, 260 00:16:34,000 --> 00:16:37,360 Speaker 1: because clearly you can't just put a human in there 261 00:16:37,400 --> 00:16:40,400 Speaker 1: and hope everything turns out all right. But it's still 262 00:16:40,400 --> 00:16:43,280 Speaker 1: a very sad story to me because I'm I'm a 263 00:16:43,320 --> 00:16:48,240 Speaker 1: squishy dog lover. I have a dog, and I when 264 00:16:48,280 --> 00:16:50,160 Speaker 1: I look at my dog and imagine what Lica was 265 00:16:50,240 --> 00:16:53,200 Speaker 1: going through, I just fall to pieces. At any rate, 266 00:16:53,240 --> 00:16:56,600 Speaker 1: the United States response to sput Nick was to go 267 00:16:56,680 --> 00:17:00,000 Speaker 1: back to the drawing board. They had their Vanguard design 268 00:17:00,000 --> 00:17:03,080 Speaker 1: mind that they had planned to launch, but that now 269 00:17:03,200 --> 00:17:07,480 Speaker 1: felt that it was no longer a strong enough offering. 270 00:17:07,520 --> 00:17:10,720 Speaker 1: They needed to come up with a better satellite to 271 00:17:10,880 --> 00:17:15,920 Speaker 1: really be a good response to the Soviet Union's project. 272 00:17:16,320 --> 00:17:20,760 Speaker 1: So the new USA project was called Explorer, and it 273 00:17:20,800 --> 00:17:24,840 Speaker 1: was led by a rocket scientist named Werner von Brown. 274 00:17:26,080 --> 00:17:33,000 Speaker 1: Von Brown was a brilliant physicist, a very intelligent rockets scientist, 275 00:17:33,080 --> 00:17:37,720 Speaker 1: but he had an incredibly dark past. UH. He was 276 00:17:37,760 --> 00:17:40,760 Speaker 1: born in Germany in nineteen twelve and he was part 277 00:17:40,800 --> 00:17:43,680 Speaker 1: of the Rocket Society as early as nineteen twenty nine. 278 00:17:44,280 --> 00:17:48,320 Speaker 1: As the Nazis gained power in Germany during the thirties, 279 00:17:48,960 --> 00:17:51,760 Speaker 1: Von Brown chose to work for the German Army to 280 00:17:51,840 --> 00:17:55,480 Speaker 1: develop missiles. He wanted to continue his research and work, 281 00:17:55,920 --> 00:17:59,600 Speaker 1: and it seemed like the UH the most opportune place, 282 00:18:00,600 --> 00:18:03,199 Speaker 1: and his work was instrumental in the development of the 283 00:18:03,320 --> 00:18:08,440 Speaker 1: V two ballistic missile, which was a tool the Nazis 284 00:18:08,640 --> 00:18:11,600 Speaker 1: used to some effect, perhaps not as great as it 285 00:18:11,600 --> 00:18:14,760 Speaker 1: could have been, but certainly was a destructive weapon that 286 00:18:14,880 --> 00:18:19,760 Speaker 1: caused a lot of damage and death. He was eventually 287 00:18:19,800 --> 00:18:23,800 Speaker 1: awarded an honorary rank in the s S by Heinrich Himmler. 288 00:18:24,640 --> 00:18:28,160 Speaker 1: It is said, however, that von Brown only accepted that 289 00:18:28,240 --> 00:18:30,880 Speaker 1: rank because he and his team were worried that Himmler 290 00:18:30,880 --> 00:18:35,320 Speaker 1: would be angry if he had declined it. So at 291 00:18:35,400 --> 00:18:39,000 Speaker 1: least some accounts state that von Brown didn't share the 292 00:18:39,040 --> 00:18:43,520 Speaker 1: political ideology of the Nazis. He just saw this as 293 00:18:43,600 --> 00:18:46,640 Speaker 1: the opportunity for him to actually do his work, and 294 00:18:46,800 --> 00:18:49,800 Speaker 1: if he didn't join the Nazis then he would not 295 00:18:49,920 --> 00:18:54,240 Speaker 1: be able to do his work. Von Brown realized that 296 00:18:54,280 --> 00:18:56,879 Speaker 1: Germany would lose the war. I think a lot of 297 00:18:56,920 --> 00:18:59,480 Speaker 1: people realized that it was getting to a point where 298 00:18:59,480 --> 00:19:02,800 Speaker 1: it was deniable, and so he made plans to surrender 299 00:19:02,920 --> 00:19:06,520 Speaker 1: himself and his team of around five rockets scientists to 300 00:19:06,640 --> 00:19:09,720 Speaker 1: the Allies and offered to do research for the United 301 00:19:09,720 --> 00:19:14,399 Speaker 1: States to help them develop their ballistic missiles. Further So, 302 00:19:14,520 --> 00:19:18,440 Speaker 1: Fan Brown and his scientists would create a rocket research 303 00:19:18,520 --> 00:19:22,480 Speaker 1: center that originally fell under the guidance of the United 304 00:19:22,480 --> 00:19:25,800 Speaker 1: States Army, but eventually it would get shifted to a 305 00:19:25,840 --> 00:19:30,800 Speaker 1: new organization called NASA, which was founded mainly in reaction 306 00:19:30,880 --> 00:19:35,040 Speaker 1: to spot Nick and really be part of the space race. 307 00:19:36,040 --> 00:19:39,880 Speaker 1: Explorer one would launch on January thirty one, nineteen eight, 308 00:19:40,480 --> 00:19:45,520 Speaker 1: and it made an actual scientific discovery on its orbital flight. 309 00:19:45,680 --> 00:19:50,400 Speaker 1: It discovered magnetic radiation belts around the Earth, which are 310 00:19:50,600 --> 00:19:54,520 Speaker 1: now called the Van Allen Belt after one of the 311 00:19:54,920 --> 00:19:59,800 Speaker 1: lead researcher on the project. Now, these days, satellites are 312 00:20:00,040 --> 00:20:04,280 Speaker 1: way more sophisticated than spot Nick or even Explorer one, 313 00:20:04,359 --> 00:20:07,800 Speaker 1: and they typically use solar panels to capture solar energy 314 00:20:07,800 --> 00:20:11,200 Speaker 1: and convert it into electricity that's used to charge batteries 315 00:20:11,200 --> 00:20:13,920 Speaker 1: for power. Some of them actually use fuel cells rather 316 00:20:13,960 --> 00:20:18,520 Speaker 1: than batteries to generate electricity, And we've used nuclear power 317 00:20:18,600 --> 00:20:21,560 Speaker 1: in some probes that we've sent away from our planet, 318 00:20:21,600 --> 00:20:23,640 Speaker 1: but in general we tend to be a bit skittish 319 00:20:23,680 --> 00:20:27,520 Speaker 1: about the idea of putting nuclear power into stuff that's 320 00:20:27,560 --> 00:20:32,119 Speaker 1: going to be orbiting our own planet. Satellites tend to 321 00:20:32,160 --> 00:20:34,840 Speaker 1: have some pretty sophisticated stuff inside them these days, like 322 00:20:34,880 --> 00:20:38,520 Speaker 1: computer control systems, which were well beyond the abilities of 323 00:20:38,560 --> 00:20:43,120 Speaker 1: the early satellites which had electro mechanical controls. But now 324 00:20:43,119 --> 00:20:48,160 Speaker 1: we've got computer control systems, radio communications, attitude control systems. 325 00:20:48,359 --> 00:20:52,199 Speaker 1: Attitude in this case isn't about personality, but rather the 326 00:20:52,200 --> 00:20:55,560 Speaker 1: satellites orientation with respect to the position of the Earth, 327 00:20:56,160 --> 00:20:59,800 Speaker 1: and satellites can have different shaped orbits. Some have circular 328 00:20:59,880 --> 00:21:03,560 Speaker 1: or bits, which are very regular and uh and predictable, 329 00:21:04,160 --> 00:21:07,720 Speaker 1: but some have elliptical orbits. And elliptical orbits are interesting 330 00:21:07,760 --> 00:21:11,600 Speaker 1: because a satellite will travel at different speeds along its 331 00:21:11,720 --> 00:21:15,680 Speaker 1: orbital path. So there are two points along that path 332 00:21:15,760 --> 00:21:19,639 Speaker 1: that we call the foci of the elliptical orbit. The 333 00:21:19,680 --> 00:21:23,800 Speaker 1: point that's closest to the planet is the parage, and 334 00:21:23,920 --> 00:21:26,600 Speaker 1: that's the point at which the satellite will be moving 335 00:21:26,680 --> 00:21:29,320 Speaker 1: fastest through its orbit. It's like think of it like 336 00:21:29,400 --> 00:21:34,080 Speaker 1: the sling shot effect. The furthest point from a planet. 337 00:21:34,119 --> 00:21:36,880 Speaker 1: The furthest point in the orbit the satellite's orbit from 338 00:21:36,880 --> 00:21:39,800 Speaker 1: a planet is the apogee, and that's where the satellite 339 00:21:39,800 --> 00:21:44,200 Speaker 1: will move the slowest in its orbital path. Now, launching 340 00:21:44,200 --> 00:21:47,520 Speaker 1: a satellite into orbit obviously requires rockets, and in a 341 00:21:47,640 --> 00:21:50,840 Speaker 1: rocket launch, a special system is used called the inertial 342 00:21:50,920 --> 00:21:55,000 Speaker 1: guidance system, which calculates the adjustments needed to push a 343 00:21:55,040 --> 00:21:58,119 Speaker 1: satellite into the correct orbit. I'll talk about the different 344 00:21:58,200 --> 00:22:02,440 Speaker 1: orbits in a second. Typically, rockets are fired so that 345 00:22:02,480 --> 00:22:05,880 Speaker 1: they head eastward, and that means that the Earth's rotation 346 00:22:06,040 --> 00:22:09,560 Speaker 1: gives those rockets a speed boost. It's like the rockets 347 00:22:09,560 --> 00:22:11,879 Speaker 1: are actually flying faster than they really are because of 348 00:22:11,880 --> 00:22:13,960 Speaker 1: the relative motion of the Earth. If you were to 349 00:22:14,040 --> 00:22:16,439 Speaker 1: launch your rocket at the equator, you would get the 350 00:22:16,480 --> 00:22:20,080 Speaker 1: biggest boost because the Earth bulge is out there. It's 351 00:22:20,119 --> 00:22:23,760 Speaker 1: the largest diameter. So here's how you would determine the 352 00:22:23,800 --> 00:22:26,640 Speaker 1: boost you get to your speed. You take the Earth's circumference, 353 00:22:27,080 --> 00:22:30,280 Speaker 1: which is about two thousand, nine hundred miles or forty 354 00:22:30,359 --> 00:22:34,960 Speaker 1: thousand sixty kilometers. You figure out how fast the Earth rotates, 355 00:22:35,000 --> 00:22:38,640 Speaker 1: which is one full rotation in approximately twenty four hours, 356 00:22:39,000 --> 00:22:41,720 Speaker 1: which gives us a speed of around one thousand, thirty 357 00:22:41,760 --> 00:22:44,359 Speaker 1: eight miles per hour or one thousand, six hundred sixty 358 00:22:44,400 --> 00:22:47,520 Speaker 1: nine kilometers per hour. That's the rotational speed of the Earth. 359 00:22:48,280 --> 00:22:50,840 Speaker 1: That's typically that's actually at the equator. If you were 360 00:22:50,880 --> 00:22:53,800 Speaker 1: to look at a launch facility at Cape Canaveral, the 361 00:22:53,920 --> 00:22:57,760 Speaker 1: rotational speed is different because you're further north of the equator. 362 00:22:57,840 --> 00:23:01,160 Speaker 1: You're not at the thickest part of the Earth. Uh Therefore, 363 00:23:01,359 --> 00:23:07,159 Speaker 1: the circumference is smaller and you have a slower speed, 364 00:23:08,080 --> 00:23:11,320 Speaker 1: So a slower rotational speed at that point so it's 365 00:23:11,359 --> 00:23:14,560 Speaker 1: closer to around eight miles per hour or one thousand, 366 00:23:14,640 --> 00:23:17,960 Speaker 1: four hundred forty kilometers per hour, but that speed boost 367 00:23:17,960 --> 00:23:20,400 Speaker 1: gives us a big help. So to get the satellite 368 00:23:20,440 --> 00:23:23,720 Speaker 1: into orbit, you have to be going wicked fast, but 369 00:23:23,840 --> 00:23:25,719 Speaker 1: not as fast as what you would need to actually 370 00:23:25,920 --> 00:23:28,640 Speaker 1: escape Earth's gravity. So if you wanted to go out 371 00:23:28,840 --> 00:23:32,440 Speaker 1: into space and beyond Earth's gravity, you're leaving Earth orbit, 372 00:23:32,920 --> 00:23:35,040 Speaker 1: you're heading out to Mars or something. You would have 373 00:23:35,080 --> 00:23:38,240 Speaker 1: to accelerate to at least twenty five thousand, thirty nine 374 00:23:38,240 --> 00:23:42,879 Speaker 1: miles per hour or forty kilometers per hour to escape 375 00:23:42,880 --> 00:23:46,439 Speaker 1: Earth's gravity and enter outer space. Putting a satellite in 376 00:23:46,520 --> 00:23:50,119 Speaker 1: orbit requires less speed, and it all depends upon which 377 00:23:50,240 --> 00:23:54,399 Speaker 1: orbit you're trying to insert the satellite into. The orbits 378 00:23:54,440 --> 00:23:58,840 Speaker 1: determine the speed, so lower orbits require faster speeds, which 379 00:23:58,920 --> 00:24:01,200 Speaker 1: might seem counter and tuitive at first, but you gotta 380 00:24:01,240 --> 00:24:04,840 Speaker 1: remember those lower orbits that that speed is meant to 381 00:24:05,200 --> 00:24:09,800 Speaker 1: counteract the gravitational pull of Earth so that the object 382 00:24:09,800 --> 00:24:12,520 Speaker 1: in orbit remains in orbit doesn't get pulled back down 383 00:24:12,560 --> 00:24:15,760 Speaker 1: to the ground. So when you're closer to Earth, the 384 00:24:15,800 --> 00:24:19,880 Speaker 1: force of gravity is greater, as you probably Remember, gravity 385 00:24:19,920 --> 00:24:23,720 Speaker 1: is dependent upon two things, the mass of two objects 386 00:24:23,840 --> 00:24:27,480 Speaker 1: and their relative distance to one another. So as distance 387 00:24:27,520 --> 00:24:32,040 Speaker 1: increases gravitation, gravitational pull decreases, and you don't need to 388 00:24:32,080 --> 00:24:35,800 Speaker 1: counteract that with more velocity to make sure an object 389 00:24:35,880 --> 00:24:39,320 Speaker 1: stays within its orbital path and doesn't deteriorate and fall 390 00:24:39,400 --> 00:24:43,199 Speaker 1: into the Earth. So higher orbits require lower speeds, and 391 00:24:43,200 --> 00:24:45,320 Speaker 1: if you get far enough out there, you can have 392 00:24:45,359 --> 00:24:49,840 Speaker 1: a satellite that orbits at the same speed as Earth's rotation. Uh, 393 00:24:49,880 --> 00:24:53,480 Speaker 1: those would be geostationary orbits. They would appear to be 394 00:24:53,640 --> 00:24:56,280 Speaker 1: directly above a fixed point on the Earth and they 395 00:24:56,280 --> 00:24:59,679 Speaker 1: would not move from that point. I'll get into that 396 00:24:59,720 --> 00:25:03,399 Speaker 1: more just a second. First, let's talk about the various 397 00:25:03,440 --> 00:25:06,880 Speaker 1: types of orbits from an altitude, because we can describe 398 00:25:06,960 --> 00:25:10,160 Speaker 1: orbits in different ways. You can describe their orbital pathway 399 00:25:10,160 --> 00:25:13,520 Speaker 1: whether it's circular or elliptical. You can describe it in 400 00:25:13,600 --> 00:25:16,600 Speaker 1: its altitude, and you can describe it in its orientation 401 00:25:16,680 --> 00:25:20,200 Speaker 1: as in is it equatorial, is it directly above the equator? 402 00:25:20,760 --> 00:25:24,320 Speaker 1: Is there any degree of inclination? Um? Is it a 403 00:25:24,400 --> 00:25:28,440 Speaker 1: polar orbit which goes north south not east west? Lots 404 00:25:28,440 --> 00:25:31,520 Speaker 1: of different ways to describe them. So from an altitude perspective, 405 00:25:31,560 --> 00:25:34,239 Speaker 1: we start with lower orbit. That's the one closest end 406 00:25:34,240 --> 00:25:36,919 Speaker 1: to the Earth, and that's an a range that's between 407 00:25:36,920 --> 00:25:40,160 Speaker 1: a hundred eleven miles and one thousand, two hundred three 408 00:25:40,160 --> 00:25:43,040 Speaker 1: miles above the surface of the Earth. In kilometers, I 409 00:25:43,040 --> 00:25:46,120 Speaker 1: would be a hundred eighty to two thousand uh. This 410 00:25:46,240 --> 00:25:49,679 Speaker 1: tends to be the altitude we use for satellites that 411 00:25:49,720 --> 00:25:54,120 Speaker 1: collects surface observations, photography, weather satellites, that kind of thing. 412 00:25:54,800 --> 00:25:57,800 Speaker 1: When you go further out, you get to medium Earth 413 00:25:57,880 --> 00:26:01,119 Speaker 1: orbit that's in a zone the between one thousand, two 414 00:26:01,200 --> 00:26:04,520 Speaker 1: hundred forty three miles and twenty two thousand, two hundred 415 00:26:04,560 --> 00:26:08,880 Speaker 1: twenty three miles or in kilometers way easier two thousand 416 00:26:08,920 --> 00:26:13,800 Speaker 1: to thirty six thousand kilometers. Navigation satellites like GPS tend 417 00:26:13,880 --> 00:26:17,119 Speaker 1: to be at this altitude, although summer at higher altitudes. 418 00:26:17,520 --> 00:26:20,960 Speaker 1: Then you get to geosynchronous orbit. That's when you are 419 00:26:21,000 --> 00:26:24,320 Speaker 1: at an altitude that's greater than twenty two thousand, twenty 420 00:26:24,400 --> 00:26:27,560 Speaker 1: three miles, in other words, greater than thirty six thousand kilometers. 421 00:26:27,800 --> 00:26:30,800 Speaker 1: The orbital period is the same as the Earth's rotational period, 422 00:26:30,880 --> 00:26:33,800 Speaker 1: meaning it takes a full day for the satellite to 423 00:26:33,880 --> 00:26:36,719 Speaker 1: go all the way around the Earth. There are is 424 00:26:36,760 --> 00:26:42,200 Speaker 1: a subset of geosynchronous satellites called geo stationary satellites, So 425 00:26:42,920 --> 00:26:49,320 Speaker 1: all geostationary satellites are also geosynchronous, but not all geosynchronous 426 00:26:49,359 --> 00:26:53,560 Speaker 1: satellites are geo stationary. If you have a geostationary satellite, 427 00:26:53,600 --> 00:26:55,879 Speaker 1: that's one of those satellites that remains over a fixed 428 00:26:55,920 --> 00:26:59,399 Speaker 1: position on the Earth's surface, So you could build and 429 00:26:59,680 --> 00:27:04,800 Speaker 1: enter at that point pointed straight up into the atmosphere, 430 00:27:04,840 --> 00:27:07,679 Speaker 1: and it's going to be aimed directly at that satellite. 431 00:27:08,000 --> 00:27:10,800 Speaker 1: And as long as nothing changes in that satellite's orbit. 432 00:27:11,280 --> 00:27:13,200 Speaker 1: Things do change over time, so you have to correct 433 00:27:13,280 --> 00:27:16,359 Speaker 1: it occasionally, but as long as nothing changes, uh, the 434 00:27:16,400 --> 00:27:21,040 Speaker 1: antenna and satellite will always be in alignment. That's a 435 00:27:21,080 --> 00:27:25,320 Speaker 1: geostationary satellite. Uh. It doesn't matter if it's day or night. 436 00:27:25,760 --> 00:27:28,560 Speaker 1: You're always going to have a direct line of sight 437 00:27:28,680 --> 00:27:31,119 Speaker 1: between the antenna and the satellite, and the satellite is 438 00:27:31,119 --> 00:27:32,399 Speaker 1: gonna be too far away from you to see it, 439 00:27:32,480 --> 00:27:34,439 Speaker 1: but there's a direct line of site as far as 440 00:27:34,440 --> 00:27:38,800 Speaker 1: the antenna is concerned. All geostationary satellites are geosynchronous. Like 441 00:27:38,800 --> 00:27:42,199 Speaker 1: I said, But if the opposite isn't true, what's going on? 442 00:27:42,359 --> 00:27:45,479 Speaker 1: How are geo secret as satellites that aren't geostationary. How 443 00:27:45,480 --> 00:27:49,320 Speaker 1: does that work? Well, the geosynchronous satellite does make one 444 00:27:49,440 --> 00:27:51,160 Speaker 1: orbit around the Earth in the same amount of time 445 00:27:51,160 --> 00:27:54,879 Speaker 1: it takes Earth to make one rotation in inertial or 446 00:27:54,920 --> 00:27:59,120 Speaker 1: fixed space, which is also called a sidereal day. It's 447 00:27:59,119 --> 00:28:03,480 Speaker 1: actually not twenty four hours. Specifically, it is twenty three hours, 448 00:28:03,480 --> 00:28:07,080 Speaker 1: fifty six minutes and four seconds of mean solar time. 449 00:28:08,240 --> 00:28:10,680 Speaker 1: You've got a bit more to say about how satellites work, 450 00:28:10,760 --> 00:28:12,359 Speaker 1: but before we get to that, we need to take 451 00:28:12,440 --> 00:28:26,000 Speaker 1: another quick break. If the satellite has any inclination or 452 00:28:26,040 --> 00:28:30,159 Speaker 1: a non circular orbital path, it will not be geo stationary. 453 00:28:30,800 --> 00:28:34,000 Speaker 1: The satellite will appear to roam over the Earth's surface, 454 00:28:34,040 --> 00:28:37,600 Speaker 1: so in elliptical orbits, those egg shaped orbits, the satellite 455 00:28:37,600 --> 00:28:40,840 Speaker 1: would be moving at different speeds along its journey. Remember 456 00:28:40,920 --> 00:28:43,320 Speaker 1: the paragean apogee, It's going to be moving it at 457 00:28:43,360 --> 00:28:48,400 Speaker 1: different velocities as it goes around the Earth. Inclination, by 458 00:28:48,400 --> 00:28:51,360 Speaker 1: the way, is the angle between a reference plane and 459 00:28:51,440 --> 00:28:55,680 Speaker 1: the orbital plane. The reference plane in this case, Uh, 460 00:28:55,600 --> 00:28:59,680 Speaker 1: we're talking specifically about the equator. So imagine you've got 461 00:28:59,680 --> 00:29:02,520 Speaker 1: the Earth globe, you've got it tilted at a slight 462 00:29:02,560 --> 00:29:04,920 Speaker 1: angle because the axis is on an angle, and you've 463 00:29:04,920 --> 00:29:09,480 Speaker 1: got the equator. If you have a geosynchronous satellite directly 464 00:29:09,520 --> 00:29:13,560 Speaker 1: above the equator, it's going to be geo stationary. It's 465 00:29:13,560 --> 00:29:16,320 Speaker 1: going to stay around that fixed point. But if you 466 00:29:16,360 --> 00:29:20,520 Speaker 1: go north or south of the equator and you place 467 00:29:20,680 --> 00:29:24,240 Speaker 1: a satellite there, it will it will not stay above 468 00:29:24,280 --> 00:29:28,000 Speaker 1: a fixed point. Its orbit is going to be slightly angled. 469 00:29:28,320 --> 00:29:32,480 Speaker 1: That's the inclination we would talk about. UH, So as 470 00:29:32,480 --> 00:29:36,680 Speaker 1: it would go around the pathway, uh, it would actually 471 00:29:36,960 --> 00:29:40,120 Speaker 1: roam over the surface of the Earth. So a satellite 472 00:29:40,120 --> 00:29:42,440 Speaker 1: that has degrees of inclination and its orbit with respect 473 00:29:42,480 --> 00:29:45,160 Speaker 1: to the equator will move north and south of the 474 00:29:45,160 --> 00:29:49,080 Speaker 1: equator as it completes an orbit. So this satellite is 475 00:29:49,120 --> 00:29:51,720 Speaker 1: going to stay more or less in the same east 476 00:29:51,800 --> 00:29:54,880 Speaker 1: west area, but it's going to go north south as 477 00:29:54,960 --> 00:29:58,400 Speaker 1: it goes throughout its orbit. Satellites with an elliptical path 478 00:29:58,400 --> 00:30:01,200 Speaker 1: will drift east and west for any fixed point on 479 00:30:01,240 --> 00:30:04,360 Speaker 1: the Earth. As a satellite moves faster or slower through 480 00:30:04,360 --> 00:30:07,440 Speaker 1: its Earth orbit. We have seen There are several satellites 481 00:30:07,440 --> 00:30:11,480 Speaker 1: that use this where they are both a inclination and 482 00:30:11,520 --> 00:30:14,480 Speaker 1: an elliptical path, so they make this almost like a 483 00:30:14,520 --> 00:30:18,640 Speaker 1: figure eight kind of pattern over a general region of 484 00:30:19,160 --> 00:30:22,400 Speaker 1: the Earth's surface, which could be really useful for things 485 00:30:22,400 --> 00:30:26,760 Speaker 1: like communication satellites or or even GPS in that In 486 00:30:26,800 --> 00:30:29,200 Speaker 1: that sense, there are some GPS satellites that work under 487 00:30:29,240 --> 00:30:34,600 Speaker 1: this principle. Geo stationary satellites have a view of about 488 00:30:35,400 --> 00:30:39,720 Speaker 1: of the Earth's surface. Just a single geo stationary satellite 489 00:30:39,760 --> 00:30:43,080 Speaker 1: can see about fort of the Earth's surface from where 490 00:30:43,080 --> 00:30:46,520 Speaker 1: it is. So if you just create a network of 491 00:30:46,560 --> 00:30:49,360 Speaker 1: a few geostationary satellites, you can get a view of 492 00:30:50,080 --> 00:30:54,240 Speaker 1: practically the entire Earth, really everything between eighty one degree 493 00:30:54,280 --> 00:30:57,640 Speaker 1: south and eighty one degrees north. Beyond those those uh 494 00:30:57,920 --> 00:31:00,239 Speaker 1: those degrees, you wouldn't be able to see it from 495 00:31:00,280 --> 00:31:02,720 Speaker 1: the way the Earth is curved, but you'd get to 496 00:31:02,760 --> 00:31:07,240 Speaker 1: see everything between the two. Geo stationary satellites tend to 497 00:31:07,240 --> 00:31:10,000 Speaker 1: be used for communications. That's great solution for us on 498 00:31:10,040 --> 00:31:12,640 Speaker 1: the ground because you don't need to move the antenna 499 00:31:12,720 --> 00:31:15,400 Speaker 1: on the surface to stay in contact with the satellite. 500 00:31:16,080 --> 00:31:19,120 Speaker 1: If the satellite we're drifting if it if it orbited 501 00:31:19,160 --> 00:31:23,080 Speaker 1: the Earth multiple times during a rotation, you would constantly 502 00:31:23,120 --> 00:31:26,160 Speaker 1: have to adjust your antenna to remain in contact with 503 00:31:26,200 --> 00:31:28,680 Speaker 1: the satellite, and there will be times where you would 504 00:31:28,680 --> 00:31:30,760 Speaker 1: be out of contact with the satellite. It would have 505 00:31:30,800 --> 00:31:35,080 Speaker 1: the Earth between you and the antenna. So geo stationary 506 00:31:35,160 --> 00:31:37,800 Speaker 1: makes this easy because it's always going to be directly 507 00:31:37,840 --> 00:31:41,960 Speaker 1: above the antenna. So it makes an ideal communication satellite 508 00:31:41,960 --> 00:31:45,800 Speaker 1: in that respect. But there are a limited number of 509 00:31:45,880 --> 00:31:49,480 Speaker 1: slots for geostationary satellites. You know, you could go to 510 00:31:49,560 --> 00:31:51,760 Speaker 1: different altitudes, but you're going to be You're going to 511 00:31:51,840 --> 00:31:55,760 Speaker 1: be stuck at that equator plane. So you don't want 512 00:31:55,880 --> 00:31:59,440 Speaker 1: satellites to collide with one another. Obviously, that would destroy 513 00:31:59,680 --> 00:32:04,200 Speaker 1: or an least damage one or both satellites, and you 514 00:32:04,280 --> 00:32:08,320 Speaker 1: don't want the actual data communication to interfere with each other, 515 00:32:08,440 --> 00:32:11,160 Speaker 1: so you have to separate them out by space. You 516 00:32:11,200 --> 00:32:14,680 Speaker 1: can't have them to pack pecked in too closely together, 517 00:32:15,920 --> 00:32:19,280 Speaker 1: and a satellite geo stationary orbit will not stay there forever. 518 00:32:19,360 --> 00:32:22,480 Speaker 1: Other gravitational forces from the Sun and the Moon, plus 519 00:32:22,480 --> 00:32:25,600 Speaker 1: the fact that the Earth is not perfectly round, will 520 00:32:25,680 --> 00:32:30,320 Speaker 1: cause the satellites to increase in inclination over time, so 521 00:32:30,360 --> 00:32:33,280 Speaker 1: they'll they'll start to drift a little bit and then 522 00:32:33,320 --> 00:32:37,120 Speaker 1: they will no longer be geo stationary UH satellites. They'll 523 00:32:37,160 --> 00:32:40,440 Speaker 1: have thrusters on them and fuel inside them in order 524 00:32:40,440 --> 00:32:44,520 Speaker 1: to make small corrections, which is called station keeping, and 525 00:32:44,560 --> 00:32:47,560 Speaker 1: that's so that they can stay in the right relative location. 526 00:32:48,800 --> 00:32:50,800 Speaker 1: But once the satellite is used up all its fuel, 527 00:32:51,000 --> 00:32:54,200 Speaker 1: it will experience an increase in inclination. It's unavoidable. You 528 00:32:54,280 --> 00:32:58,120 Speaker 1: can't fix it at that point, and it's possible, depending 529 00:32:58,200 --> 00:33:01,440 Speaker 1: upon how the satellite is located, that it could become 530 00:33:01,480 --> 00:33:05,600 Speaker 1: a hazard to other geo stationary or geosynchronous satellites. So 531 00:33:05,680 --> 00:33:09,200 Speaker 1: normally at the end of a geo stationary satellites useful 532 00:33:09,240 --> 00:33:13,200 Speaker 1: LIFESPAN will send a command to the satellite to say, 533 00:33:13,360 --> 00:33:15,520 Speaker 1: get the heck out of the neighborhood. Boost it at 534 00:33:15,560 --> 00:33:18,720 Speaker 1: a higher altitude, a higher orbit, which moves out of 535 00:33:18,760 --> 00:33:21,160 Speaker 1: the way of other satellites, because it's not gonna be 536 00:33:21,240 --> 00:33:23,720 Speaker 1: useful anyway, so you might as well boost it further 537 00:33:23,800 --> 00:33:27,040 Speaker 1: out and not have it become space junk closer into 538 00:33:27,080 --> 00:33:29,280 Speaker 1: the Earth. There's already a lot of space junk that's 539 00:33:29,280 --> 00:33:33,040 Speaker 1: out there. Fortunately, space is really big. So while there's 540 00:33:33,080 --> 00:33:36,280 Speaker 1: always a threat of space junk being a problem with satellites, 541 00:33:37,320 --> 00:33:41,280 Speaker 1: it's such a huge space that the odds on any 542 00:33:41,480 --> 00:33:45,040 Speaker 1: given day are fairly low of an incident. But the 543 00:33:45,080 --> 00:33:48,000 Speaker 1: more stuff we send up there, the better the odds 544 00:33:48,040 --> 00:33:51,719 Speaker 1: are that something bad will happen. Now, not all orbits 545 00:33:51,720 --> 00:33:55,360 Speaker 1: are in an east west orientation. You're probably imagining that 546 00:33:55,400 --> 00:33:58,920 Speaker 1: these satellites are orbiting the Earth more or less in 547 00:33:58,960 --> 00:34:02,080 Speaker 1: the same direct shouldn't that the Earth rotates, that they 548 00:34:02,120 --> 00:34:06,520 Speaker 1: are going around and around, uh, the same axis of rotation. 549 00:34:07,280 --> 00:34:09,719 Speaker 1: Not all of them do. Some of them are rotating 550 00:34:09,800 --> 00:34:14,120 Speaker 1: north south, they're going around the poles. You have polar orbits, 551 00:34:14,960 --> 00:34:18,560 Speaker 1: which are really good for photography and mapping because as 552 00:34:18,640 --> 00:34:21,920 Speaker 1: these satellites move north to south or south and north, 553 00:34:22,160 --> 00:34:25,320 Speaker 1: depending upon which way you're going, um, the Earth is 554 00:34:25,480 --> 00:34:29,320 Speaker 1: rotating under the satellites, so they get a really good 555 00:34:29,400 --> 00:34:32,800 Speaker 1: view of the Earth. They're great if you want to 556 00:34:32,920 --> 00:34:36,719 Speaker 1: have a satellite map of a region. They're also not 557 00:34:36,800 --> 00:34:40,319 Speaker 1: bad if you're hoping for satellite to pass over a 558 00:34:40,320 --> 00:34:42,360 Speaker 1: certain region on the Earth so you can get a 559 00:34:42,360 --> 00:34:45,160 Speaker 1: better look. In other words, these are used for spying, 560 00:34:46,480 --> 00:34:50,560 Speaker 1: and one particular type of orbit, very specific type of 561 00:34:50,640 --> 00:34:55,479 Speaker 1: orbit is the mulnia or lightning orbit, and the orbit 562 00:34:55,520 --> 00:34:59,120 Speaker 1: takes its name from Soviet satellites that use this particular 563 00:34:59,120 --> 00:35:03,160 Speaker 1: style of orbit or communications networks. It's an elliptical shape, 564 00:35:03,600 --> 00:35:06,040 Speaker 1: which means the satellite spends a lot of its time 565 00:35:06,120 --> 00:35:10,399 Speaker 1: near the apoge poet point the of the orbit, because 566 00:35:10,400 --> 00:35:14,680 Speaker 1: that's where it moves the slowest. So if you plan 567 00:35:14,800 --> 00:35:17,160 Speaker 1: out the telemetry of your satellite in such a way 568 00:35:17,200 --> 00:35:20,080 Speaker 1: so that the apoge is over a specific region, you 569 00:35:20,120 --> 00:35:23,520 Speaker 1: know that when the satellite orbits the Earth, it's gonna 570 00:35:23,520 --> 00:35:27,560 Speaker 1: be spending the majority of its orbit over where the 571 00:35:27,600 --> 00:35:31,120 Speaker 1: apogee is. So if you locate it in a place 572 00:35:31,160 --> 00:35:34,319 Speaker 1: that you're interested in, you're gonna get more coverage of 573 00:35:34,360 --> 00:35:38,520 Speaker 1: that region throughout the duration of the orbit of the satellite. 574 00:35:39,200 --> 00:35:41,239 Speaker 1: So the Soviets planned the apoge to be over the 575 00:35:41,280 --> 00:35:44,080 Speaker 1: northern hemisphere so that they could serve as a communications 576 00:35:44,080 --> 00:35:46,960 Speaker 1: network and maybe also you know, spy on Europe a 577 00:35:47,000 --> 00:35:50,640 Speaker 1: little bit. Perhaps one thing we use satellites for is 578 00:35:50,680 --> 00:35:54,479 Speaker 1: to spread a signal from one location to another, and 579 00:35:54,640 --> 00:35:57,480 Speaker 1: this is a pretty simple idea. Actually, it's just bouncing 580 00:35:57,640 --> 00:36:00,400 Speaker 1: a signal off of a satellite. It's amost like the 581 00:36:00,400 --> 00:36:03,480 Speaker 1: satellite acts as a mirror, although it's also an amplifier. 582 00:36:03,560 --> 00:36:06,560 Speaker 1: So we use an antenna on the Earth pointed up 583 00:36:06,600 --> 00:36:09,759 Speaker 1: towards the satellite we're interested in, and we beam a 584 00:36:09,840 --> 00:36:13,000 Speaker 1: signal into space. It might be audio, it might be video, 585 00:36:13,040 --> 00:36:15,600 Speaker 1: it could be anything really, and that antenna is the 586 00:36:15,719 --> 00:36:19,200 Speaker 1: up link. Now the satellite receives this. They have it 587 00:36:19,239 --> 00:36:22,359 Speaker 1: has its own antenna and receives the signal and then 588 00:36:22,560 --> 00:36:25,920 Speaker 1: runs it through an amplifier and the beams the amplified 589 00:36:25,920 --> 00:36:30,160 Speaker 1: signal back down to the Earth. And on Earth we 590 00:36:30,200 --> 00:36:34,200 Speaker 1: have other antenna known as the down links, that receive 591 00:36:34,400 --> 00:36:37,479 Speaker 1: the incoming signal from the satellite. And using this model, 592 00:36:37,520 --> 00:36:40,640 Speaker 1: we can beam all sorts of useful stuff like communication signals. 593 00:36:41,120 --> 00:36:44,719 Speaker 1: Television studios would send feeds up to satellites, which then 594 00:36:44,760 --> 00:36:47,480 Speaker 1: act as a distribution system. So you would have a 595 00:36:47,480 --> 00:36:51,200 Speaker 1: centralized location where you would have the the video feed, 596 00:36:51,320 --> 00:36:54,279 Speaker 1: video and audio feed. You would send that through an 597 00:36:54,320 --> 00:36:56,880 Speaker 1: up link to a satellite. It would receive it and 598 00:36:56,920 --> 00:37:00,440 Speaker 1: beam it back down to receiving stations. And that was 599 00:37:00,480 --> 00:37:05,040 Speaker 1: how you know, that's how we get television broadcast beyond 600 00:37:05,160 --> 00:37:08,239 Speaker 1: just over the air broadcast. In fact, if you have 601 00:37:08,520 --> 00:37:14,239 Speaker 1: a cable company, you could receive these signals yourself using satellites. Right, 602 00:37:14,320 --> 00:37:16,719 Speaker 1: you could have part of the satellite TV system and 603 00:37:16,760 --> 00:37:19,520 Speaker 1: you have your own little satellite that's pointed up and 604 00:37:19,560 --> 00:37:23,400 Speaker 1: you receive your television signals that way. Or you could 605 00:37:23,480 --> 00:37:27,480 Speaker 1: end up having cable but cable companies also use this method. 606 00:37:27,560 --> 00:37:30,319 Speaker 1: You would have a centralized location that beams a signal up, 607 00:37:30,640 --> 00:37:34,560 Speaker 1: it comes down so that various cable distribution networks received 608 00:37:34,640 --> 00:37:37,400 Speaker 1: the signal and then they send that through the actual 609 00:37:37,480 --> 00:37:42,480 Speaker 1: cables that eventually terminate at your television. So this is 610 00:37:42,520 --> 00:37:46,759 Speaker 1: a very important way of using satellites. Now, I want 611 00:37:46,760 --> 00:37:50,279 Speaker 1: to conclude this episode with a quick discussion about how 612 00:37:50,360 --> 00:37:56,839 Speaker 1: relativity affects satellites, both special and general relativity. Now, these, 613 00:37:56,880 --> 00:38:00,400 Speaker 1: of course are the the theories proposed by Einstein that 614 00:38:00,640 --> 00:38:05,320 Speaker 1: ultimately proved true at least in the case of time dilation, 615 00:38:05,800 --> 00:38:09,719 Speaker 1: because we see it in practice with satellites. One of 616 00:38:09,760 --> 00:38:13,040 Speaker 1: the things we use satellites for is GPS, the Global 617 00:38:13,080 --> 00:38:18,560 Speaker 1: Position System. So GPS positioning system, I should say, and 618 00:38:18,560 --> 00:38:22,000 Speaker 1: GPS is incredibly useful. That's what lets us use real 619 00:38:22,080 --> 00:38:26,080 Speaker 1: time maps on our phones and GPS devices to go 620 00:38:26,280 --> 00:38:29,319 Speaker 1: from point A to point B. But in order for 621 00:38:29,360 --> 00:38:33,080 Speaker 1: GPS to work, it needs to be able to measure 622 00:38:33,160 --> 00:38:37,320 Speaker 1: time very accurately, both for the person who's on Earth 623 00:38:37,440 --> 00:38:40,960 Speaker 1: and the satellite that is providing the very satellites I 624 00:38:40,960 --> 00:38:43,880 Speaker 1: should say that are providing the information that allows us 625 00:38:43,920 --> 00:38:47,280 Speaker 1: to UH to triangulate where we are on the service 626 00:38:47,280 --> 00:38:52,440 Speaker 1: of Earth. So here's the problem. Time dilation. Einstein's theory 627 00:38:53,480 --> 00:38:57,320 Speaker 1: gives us some uh some issues with time. Special relativity 628 00:38:57,360 --> 00:39:02,560 Speaker 1: tells us that the faster we move relative to an 629 00:39:02,640 --> 00:39:07,960 Speaker 1: independent observer, the slower time seems to pass for ourselves. 630 00:39:08,560 --> 00:39:12,759 Speaker 1: Um again, based upon the relative observer to us, time 631 00:39:12,760 --> 00:39:15,239 Speaker 1: will pass exactly the same way. No matter how fast 632 00:39:15,280 --> 00:39:17,879 Speaker 1: we're going we will it will feel the same. So 633 00:39:18,040 --> 00:39:21,160 Speaker 1: if you get on a spaceship that's going near the 634 00:39:21,200 --> 00:39:23,359 Speaker 1: speed of light and you look at your watch, the 635 00:39:23,400 --> 00:39:26,319 Speaker 1: second hand is going to take away as if you 636 00:39:26,360 --> 00:39:30,960 Speaker 1: were on Earth. But to an independent observer, it would 637 00:39:31,000 --> 00:39:35,879 Speaker 1: look like that second hand is going super slow, and 638 00:39:36,000 --> 00:39:38,080 Speaker 1: it would mean that when you finished your journey and 639 00:39:38,160 --> 00:39:41,200 Speaker 1: came back to Earth, more time would appear to have 640 00:39:41,239 --> 00:39:44,560 Speaker 1: passed on Earth than it did for you, even though 641 00:39:44,920 --> 00:39:48,440 Speaker 1: for people on Earth, time was passing normally. For you 642 00:39:48,520 --> 00:39:51,279 Speaker 1: on the spaceship, time was passing normally. It's really only 643 00:39:51,320 --> 00:39:53,839 Speaker 1: when you have this point of reference that you realize 644 00:39:54,080 --> 00:39:59,000 Speaker 1: that you've experienced different amounts of time. Uh, it's kind 645 00:39:59,000 --> 00:40:03,520 Speaker 1: of a mind bender. Well, special relativity tells us that 646 00:40:04,000 --> 00:40:06,840 Speaker 1: these clocks on board the satellites will take a little 647 00:40:06,840 --> 00:40:10,760 Speaker 1: more slowly because they're moving so fast out in space. 648 00:40:11,719 --> 00:40:15,520 Speaker 1: They should actually fall behind the clocks here on Earth 649 00:40:15,680 --> 00:40:19,520 Speaker 1: by about seven micro seconds per day, which doesn't sound 650 00:40:19,560 --> 00:40:22,440 Speaker 1: like a lot, but if you're talking about very precise 651 00:40:22,480 --> 00:40:24,799 Speaker 1: measurements to give you an idea of where you are 652 00:40:26,120 --> 00:40:31,000 Speaker 1: before long, that becomes an insurmountable problem. So seven micro 653 00:40:31,080 --> 00:40:35,920 Speaker 1: seconds per day slower on the satellites compared to the 654 00:40:35,960 --> 00:40:38,600 Speaker 1: clocks on Earth. If that were all there were to it, 655 00:40:39,080 --> 00:40:40,959 Speaker 1: then we would just say, well, we have to find 656 00:40:41,000 --> 00:40:43,279 Speaker 1: a way, like a program that will build in this 657 00:40:43,480 --> 00:40:46,000 Speaker 1: error so that we know ahead of time how to 658 00:40:46,440 --> 00:40:49,319 Speaker 1: adjust for it. But it gets more complicated than that. 659 00:40:50,200 --> 00:40:55,239 Speaker 1: So that's special relativity. But general relativity also plays a part. 660 00:40:55,840 --> 00:40:59,759 Speaker 1: So one of the predictions made by general relativity is 661 00:40:59,800 --> 00:41:03,480 Speaker 1: that clocks closer to a massive object will seem to 662 00:41:03,520 --> 00:41:07,680 Speaker 1: take more slowly than those that are further away from 663 00:41:07,680 --> 00:41:12,120 Speaker 1: a massive object. So if we look at it that way, 664 00:41:12,160 --> 00:41:14,520 Speaker 1: these satellites are very far away from the surface of 665 00:41:14,520 --> 00:41:16,680 Speaker 1: the Earth, so the clocks on the surface of the 666 00:41:16,680 --> 00:41:19,480 Speaker 1: Earth are much closer to a massive object. The clocks 667 00:41:19,480 --> 00:41:22,560 Speaker 1: on the satellites are much further away from a massive object, 668 00:41:23,080 --> 00:41:25,759 Speaker 1: and it's enough to make a big difference. It also 669 00:41:25,800 --> 00:41:27,880 Speaker 1: means that the clocks on the satellites appear to be 670 00:41:27,960 --> 00:41:32,799 Speaker 1: taking faster than the clocks on the ground. So if 671 00:41:32,840 --> 00:41:37,760 Speaker 1: you calculate a prediction using general relativity as your basis 672 00:41:38,320 --> 00:41:41,080 Speaker 1: for how fast those clocks will be ticking on the satellites, 673 00:41:41,520 --> 00:41:43,960 Speaker 1: you would see that they be ahead of our ground 674 00:41:44,040 --> 00:41:47,759 Speaker 1: clocks by about forty five micro seconds per day. Now, 675 00:41:47,800 --> 00:41:49,760 Speaker 1: this actually means that you have to take the difference 676 00:41:49,840 --> 00:41:53,640 Speaker 1: between the forty five seconds in advance and the our 677 00:41:53,800 --> 00:41:57,000 Speaker 1: forty five micro seconds I'm sorry, forty five micro seconds 678 00:41:57,040 --> 00:42:00,239 Speaker 1: in advance from general relativity, and you have to act 679 00:42:00,239 --> 00:42:04,480 Speaker 1: the seven micro seconds behind from special relativity. And it 680 00:42:04,520 --> 00:42:08,160 Speaker 1: tells you that the clocks on board the satellites should 681 00:42:08,200 --> 00:42:11,160 Speaker 1: take a little bit faster than the clocks here on 682 00:42:11,200 --> 00:42:14,440 Speaker 1: the ground. By the tune of thirty eight microseconds per day. 683 00:42:14,680 --> 00:42:18,759 Speaker 1: You take those forty microseconds ahead general relativity, subtract the 684 00:42:18,800 --> 00:42:22,040 Speaker 1: seven microseconds from behind from special relativity, and you get 685 00:42:22,040 --> 00:42:28,640 Speaker 1: thirty eight microseconds ahead uh net. So it again is 686 00:42:28,800 --> 00:42:32,799 Speaker 1: enough for it to cause a high precision system like 687 00:42:32,880 --> 00:42:37,960 Speaker 1: GPS two have errors after just a few days, so 688 00:42:38,760 --> 00:42:41,759 Speaker 1: you have to correct for that. You actually have to 689 00:42:41,960 --> 00:42:49,600 Speaker 1: create a navigational fix so that the system is accurate. Uh. 690 00:42:49,680 --> 00:42:53,359 Speaker 1: Otherwise you would get errors in where the map would 691 00:42:53,360 --> 00:42:54,799 Speaker 1: say you were. You would look at the map and 692 00:42:54,920 --> 00:42:57,200 Speaker 1: as time would go by, these errors would get worse 693 00:42:57,200 --> 00:43:00,279 Speaker 1: and worse, to the point where it would show you 694 00:43:00,520 --> 00:43:04,759 Speaker 1: locations that are just ridiculous, you blocks away from where 695 00:43:04,760 --> 00:43:08,759 Speaker 1: you actually were, and uh and more if time went 696 00:43:08,800 --> 00:43:13,080 Speaker 1: on long enough. In the GPS satellite system was limited, 697 00:43:13,560 --> 00:43:17,960 Speaker 1: so you're talking about you know, errors of around ten 698 00:43:18,080 --> 00:43:22,040 Speaker 1: kilometers every day. That's that's a big deal. You know, 699 00:43:22,160 --> 00:43:23,640 Speaker 1: you're trying to get from point A to point B 700 00:43:23,719 --> 00:43:26,000 Speaker 1: and you're getting errors that are ten kilometers off. That 701 00:43:26,040 --> 00:43:30,800 Speaker 1: could be disastrous. So it would actually be useless after 702 00:43:31,040 --> 00:43:34,880 Speaker 1: a very few days. That's why you have to have 703 00:43:35,280 --> 00:43:40,880 Speaker 1: algorithms built in that take these relativistic effects into account 704 00:43:41,680 --> 00:43:44,880 Speaker 1: so that the results you get on your GPS device 705 00:43:45,120 --> 00:43:48,520 Speaker 1: remain accurate. So I think that's pretty cool that you know, 706 00:43:48,600 --> 00:43:52,560 Speaker 1: satellites are a practical way for us to see how 707 00:43:52,600 --> 00:43:57,080 Speaker 1: relativity can affect us, and that relativity is in fact real. 708 00:43:57,320 --> 00:44:01,080 Speaker 1: It's it's it's not it's not quote unquote just a theory. 709 00:44:01,920 --> 00:44:04,920 Speaker 1: It's something that we can observe directly and though and 710 00:44:05,000 --> 00:44:08,600 Speaker 1: know that this is at play. So I wanted to 711 00:44:08,600 --> 00:44:12,840 Speaker 1: mention that because you know, it's it's pretty cool stuff. 712 00:44:12,880 --> 00:44:15,919 Speaker 1: And honestly, when I was first looking into it years ago, 713 00:44:16,320 --> 00:44:20,319 Speaker 1: when I was looking at how GPS works, I had 714 00:44:20,360 --> 00:44:24,480 Speaker 1: a handle on special relativity. I understood that the speed 715 00:44:24,760 --> 00:44:29,360 Speaker 1: of the movement of the satellites would affect how time 716 00:44:29,400 --> 00:44:33,200 Speaker 1: passes compared to what we see here on Earth on 717 00:44:33,239 --> 00:44:37,680 Speaker 1: the surface, but I was not aware of the effects 718 00:44:37,680 --> 00:44:40,200 Speaker 1: of general relativity. That was something I had to learn 719 00:44:40,280 --> 00:44:43,839 Speaker 1: when I looked up GPS back in the day, which 720 00:44:43,840 --> 00:44:47,560 Speaker 1: I think was a Tuesday, if I'm not mistaken, so 721 00:44:48,800 --> 00:44:52,719 Speaker 1: relatively obviously a very fascinating subject. I would love to 722 00:44:52,760 --> 00:44:54,880 Speaker 1: go into further detail, but I think that's more of 723 00:44:54,880 --> 00:44:57,560 Speaker 1: a stuff to blow your mind than a tech stuff topic. 724 00:44:58,360 --> 00:45:00,680 Speaker 1: We have, of course touched upon RelA ativity a few 725 00:45:00,719 --> 00:45:04,759 Speaker 1: times in our conversations about various types of technology. But 726 00:45:05,200 --> 00:45:08,040 Speaker 1: maybe one day I'll get some stuff to blow your 727 00:45:08,040 --> 00:45:10,080 Speaker 1: mind folks in here, and then we'll have a big 728 00:45:10,120 --> 00:45:14,160 Speaker 1: discussion about relativity, not just what it is, but how 729 00:45:14,280 --> 00:45:18,520 Speaker 1: it directly affects some of the things we do. All right, 730 00:45:18,520 --> 00:45:23,319 Speaker 1: So that wraps up this discussion about satellites, and I 731 00:45:23,440 --> 00:45:25,719 Speaker 1: may do a future episode where I go into board 732 00:45:25,760 --> 00:45:28,880 Speaker 1: detail about the different types of satellites, the instrumentation that 733 00:45:29,120 --> 00:45:33,520 Speaker 1: is aboard these satellites, how they work, who owns them, 734 00:45:33,840 --> 00:45:39,880 Speaker 1: maybe some interesting stories about notable discoveries that satellites have 735 00:45:40,000 --> 00:45:45,200 Speaker 1: made and notable incidents that have happened because of satellites. 736 00:45:45,920 --> 00:45:48,640 Speaker 1: I hope you enjoyed that classic episode of tech stuff 737 00:45:48,719 --> 00:45:52,120 Speaker 1: on how satellites work. I know I've talked about satellites 738 00:45:52,160 --> 00:45:54,840 Speaker 1: and how they work several times since then. I often 739 00:45:55,280 --> 00:45:58,840 Speaker 1: do kind of a truncated abbreviated version, if you will. 740 00:45:59,320 --> 00:46:02,080 Speaker 1: When I have to talk about stuff like Starlink, for example, 741 00:46:02,080 --> 00:46:06,080 Speaker 1: which is space x is uh satellite based internet service 742 00:46:06,120 --> 00:46:09,640 Speaker 1: provider and similar things, you know, I have to talk 743 00:46:09,640 --> 00:46:13,800 Speaker 1: about how the satellites get into orbit, how they maintain orbit, 744 00:46:14,160 --> 00:46:18,359 Speaker 1: what the different orbits mean, how satellites are able to 745 00:46:18,440 --> 00:46:21,759 Speaker 1: keep track of things like making sure that you know 746 00:46:21,800 --> 00:46:26,440 Speaker 1: when you're using a GPS device that you're getting accurate 747 00:46:26,480 --> 00:46:29,000 Speaker 1: information instead of something that's telling you you're in a 748 00:46:29,080 --> 00:46:32,839 Speaker 1: totally different time zone. All this is incredible technology. It's 749 00:46:32,880 --> 00:46:37,479 Speaker 1: really amazing stuff, and it's based off amazing ingenuity, and 750 00:46:37,840 --> 00:46:40,799 Speaker 1: I'll constantly be going back and talking about it. But 751 00:46:40,840 --> 00:46:44,799 Speaker 1: this is sort of the basic information about how satellites work. 752 00:46:45,080 --> 00:46:47,759 Speaker 1: So I hope you enjoyed that. If you have suggestions 753 00:46:47,760 --> 00:46:50,280 Speaker 1: for topics I should cover in future episodes of tech Stuff, 754 00:46:50,280 --> 00:46:52,080 Speaker 1: please reach out to me. One way to do that 755 00:46:52,160 --> 00:46:54,839 Speaker 1: is to download the I Heart radio app. It's free 756 00:46:54,880 --> 00:46:56,960 Speaker 1: to download. It's free to use. You can navigate over 757 00:46:57,000 --> 00:46:58,960 Speaker 1: to the tech Stuff page for using the search bar. 758 00:46:59,520 --> 00:47:01,960 Speaker 1: You can leave us a voicemail by clicking on the 759 00:47:02,000 --> 00:47:05,120 Speaker 1: little microphone icon. Leave a message up to thirty seconds 760 00:47:05,120 --> 00:47:07,960 Speaker 1: in length. If you would prefer, you can send me 761 00:47:08,040 --> 00:47:10,920 Speaker 1: your message via Twitter. The handle for the show is 762 00:47:10,960 --> 00:47:14,600 Speaker 1: text Stuff hs W and uh yeah. Just leave me 763 00:47:14,840 --> 00:47:18,040 Speaker 1: your suggestions. Maybe it's a suggestion for a topic or 764 00:47:18,040 --> 00:47:21,319 Speaker 1: a guest. I'm always eager to see what you have 765 00:47:21,440 --> 00:47:25,279 Speaker 1: to say, and I'll talk to you again really soon. 766 00:47:27,160 --> 00:47:34,200 Speaker 1: Y Text Stuff is an I Heart Radio production. For 767 00:47:34,280 --> 00:47:37,239 Speaker 1: more podcasts from my Heart Radio, visit the i heart 768 00:47:37,320 --> 00:47:40,520 Speaker 1: Radio app, Apple Podcasts, or wherever you listen to your 769 00:47:40,560 --> 00:47:41,240 Speaker 1: favorite shows.