WEBVTT - When will the Earth become uninhabitable? 0:00:03.000 --> 0:00:05.880 Welcome to Stuff to Blow Your Mind from how Stuff 0:00:05.880 --> 0:00:14.120 Works dot Com. Hey you, wasn't it stuff to blow 0:00:14.120 --> 0:00:16.080 your mind? My name is Robert Lamb and I am 0:00:16.160 --> 0:00:19.840 Christian Sega. You know, I think we live all of 0:00:19.840 --> 0:00:23.440 our lives and the knowledge and or in the denial 0:00:23.680 --> 0:00:26.720 of imperments. We know that we're not going to live forever. 0:00:27.040 --> 0:00:29.319 That people we love, the people we hate, most of 0:00:29.320 --> 0:00:32.839 the things we hold dear will simply fade away. And 0:00:32.840 --> 0:00:35.920 at the same time we can be so very resistant 0:00:35.920 --> 0:00:38.199 to change and the idea of change, we wind up 0:00:38.200 --> 0:00:41.280 taking certain things for granted, even the very planet that 0:00:41.320 --> 0:00:44.960 we live on. To invoke the Goldilocks principle, our planet 0:00:45.000 --> 0:00:47.800 is just right for life. We've got the right ingredients, 0:00:47.840 --> 0:00:50.320 the right crusts, the right temperature, the right moon, the 0:00:50.440 --> 0:00:54.600 right star, the right core, the just the right celestial neighbors. 0:00:55.000 --> 0:00:57.880 We've largely lucked out when it comes to near Earth 0:00:57.920 --> 0:01:02.320 objects in five major distinction events. Later here we are 0:01:02.360 --> 0:01:05.959 thriving within and in some cases beyond the portion of 0:01:05.959 --> 0:01:09.399 the Earth's atmosphere and climate that we evolve to thrive in. 0:01:10.240 --> 0:01:12.559 But when will it all end? When will this place 0:01:12.680 --> 0:01:16.280 become uninhabitable to us? Some of the threats are so 0:01:16.400 --> 0:01:19.840 distant that they're almost impossible to really weigh. Will we 0:01:19.880 --> 0:01:23.680 even be us when our species encounters them? Others, however, 0:01:23.920 --> 0:01:27.319 are far more pressing. Yeah, So I'm going to try 0:01:27.319 --> 0:01:29.360 to give you all an example. I'm gonna take this 0:01:29.440 --> 0:01:33.480 from the personal to the macro. Okay, yesterday I had 0:01:33.520 --> 0:01:36.960 to go to a retirement planner. I didn't have to. 0:01:37.120 --> 0:01:40.080 I chose to um a human or a website. It 0:01:40.160 --> 0:01:42.080 was a huge I did the website first, and then 0:01:42.120 --> 0:01:43.479 they said, you might want to talk to a human 0:01:43.480 --> 0:01:45.039 about this, and so I went, I had a meeting. 0:01:45.120 --> 0:01:47.840 I sat down, we like looked at forms and stuff 0:01:47.880 --> 0:01:50.440 like that. But you know, it's not I'm forty. It's 0:01:50.480 --> 0:01:52.440 not the kind of thing that I've really spent a 0:01:52.480 --> 0:01:54.480 lot of time thinking about other than just having jobs 0:01:54.520 --> 0:01:58.240 that have, for one case, building up right. Uh, And 0:01:59.760 --> 0:02:02.680 I just just really, you know, haven't thought in a 0:02:02.760 --> 0:02:06.480 future oriented way like that before. And then immediately after that, 0:02:06.520 --> 0:02:10.200 I came home and I started to research for this episode, 0:02:10.560 --> 0:02:15.079 which is essentially about planning for global annihilation, right for 0:02:15.080 --> 0:02:19.240 for getting ready for the world, for Earth specifically to 0:02:19.400 --> 0:02:22.920 be uninhabitable for us as human beings. Well and hopefully. 0:02:23.000 --> 0:02:26.760 I mean the optimistic spin on that is preventing these 0:02:26.840 --> 0:02:30.160 the events and preventing the kind of cascading effects that 0:02:30.240 --> 0:02:33.280 could leave the earth uninhabitable. Yeah, but as we get 0:02:33.360 --> 0:02:36.080 as we will get into some of them are inevitable 0:02:36.080 --> 0:02:38.520 and there's literally nothing we can do about them. But 0:02:38.600 --> 0:02:40.919 those are luckily billions of years away. Yeah, some of 0:02:40.960 --> 0:02:43.359 these things are just so far off it's pointless to 0:02:43.400 --> 0:02:47.040 worry about them. But some of them are worth worrying about, 0:02:47.040 --> 0:02:48.760 and we're going to spend some time with those as well. 0:02:48.880 --> 0:02:51.639 You know what's kind of interesting is in your intro 0:02:51.800 --> 0:02:55.560 that you presented just now, you touched on the very 0:02:55.600 --> 0:02:58.400 first topic that you and I ever worked on together, 0:02:58.560 --> 0:03:01.440 which is the Goldilocks prince bole. Do you remember I 0:03:01.480 --> 0:03:04.520 wrote a script for a brain Stuff episode like four 0:03:04.600 --> 0:03:07.560 years ago that you performed, and it was you and 0:03:07.639 --> 0:03:11.000 Kristen con and it was about the gold lux principle. 0:03:11.760 --> 0:03:15.440 And then uh, then the stuff about mass extinction. My 0:03:15.520 --> 0:03:18.280 first official episode as a co host of Stuff to 0:03:18.280 --> 0:03:20.919 Blow Your Mind was about mass extinction. So this this 0:03:21.000 --> 0:03:24.080 is interesting. Yeah, that that one was interesting because I 0:03:24.120 --> 0:03:27.079 remember that the topic was great. Uh and yet even 0:03:27.080 --> 0:03:29.720 though you know, I had plenty of interactions with with 0:03:29.800 --> 0:03:31.760 Congre previously. That was when I got to realize, oh, 0:03:31.800 --> 0:03:34.519 we have no on air chemistry to get at all. Well, 0:03:34.560 --> 0:03:36.560 that was actually that That was sort of like along 0:03:36.560 --> 0:03:37.960 the lines of what we were trying to do was 0:03:38.000 --> 0:03:40.880 we were trying to test out all the various people 0:03:41.280 --> 0:03:44.000 who did on screen stuff to see who did have 0:03:44.120 --> 0:03:47.160 chemistry yea yeah. And while we were filming that, I 0:03:47.160 --> 0:03:49.800 was like, I can I can tell we don't really 0:03:49.840 --> 0:03:51.400 have we don't have a lot of it. I don't know. 0:03:51.480 --> 0:03:53.640 People can go watch it and judge for themselves. It's 0:03:53.640 --> 0:03:56.720 out there and the content is still good. It is yeah. 0:03:57.120 --> 0:04:00.200 Uh so let's yeah, and this episode we're going to 0:04:00.280 --> 0:04:06.600 discuss some long term concerns, some short term concerns regarding 0:04:06.640 --> 0:04:09.800 the habitability of the planet Earth, as well as some 0:04:09.840 --> 0:04:13.960 sort of random concerns thrown in there. Uh. I guess 0:04:13.960 --> 0:04:15.760 you can sort of think about it in terms of 0:04:16.440 --> 0:04:19.120 a really complex board game, right where you have you 0:04:19.200 --> 0:04:24.200 have sort of the early game uh opponents or early 0:04:24.360 --> 0:04:26.479 game threats you have to deal with. You have the 0:04:26.560 --> 0:04:30.400 in game stuff, you know, the real doom counter type scenarios, 0:04:30.560 --> 0:04:32.800 and then you just have random events that may pop 0:04:32.920 --> 0:04:35.280 up and just in the game. Yeah, you're using a 0:04:35.279 --> 0:04:38.760 lot of Arkham asylum phraseology here. I like it. I 0:04:38.800 --> 0:04:41.599 like it. Uh yeah. And and also, to be clear, 0:04:41.800 --> 0:04:44.920 the reason why I was really interested in covering this, uh, 0:04:45.040 --> 0:04:47.760 even though we somehow ended up pairing this together with 0:04:47.839 --> 0:04:50.760 zoophilia on the same day as topics that we're going 0:04:50.800 --> 0:04:53.200 to discuss, it's actually because I'm working on this sci 0:04:53.240 --> 0:04:56.080 fi horror story and I want it to be about 0:04:56.800 --> 0:05:01.040 trans humans returning to an uninhabitab Earth. As I started 0:05:01.040 --> 0:05:04.680 thinking to myself, like when will Earth be uninhabitable and 0:05:04.720 --> 0:05:07.000 what will it look like? Yeah? Yeah, I mean this 0:05:07.080 --> 0:05:11.000 is a This is a common trope in in science fiction, 0:05:11.080 --> 0:05:14.599 the idea of of the world becoming poisoned of humans 0:05:14.600 --> 0:05:17.160 of course moving beyond the Earth and then coming back 0:05:17.200 --> 0:05:21.400 to it. Yeah, and in some cases the Earth is gone. Um, 0:05:21.640 --> 0:05:24.320 if I remember correctly, in the in the Dune books, 0:05:25.040 --> 0:05:28.200 it's reference that the original terror, the original Earth no 0:05:28.279 --> 0:05:31.360 longer exists. Is that right? I didn't even know that 0:05:31.440 --> 0:05:36.400 they acknowledged any connection to actual like humanity. Okay, yeah, well, 0:05:36.440 --> 0:05:40.560 the like the Tradees are supposed to be um descendants 0:05:40.600 --> 0:05:44.920 of the Greeks, is that right, But but I believe 0:05:44.920 --> 0:05:48.600 it's it's what God Emperor of Dune. In one of 0:05:48.000 --> 0:05:52.679 the many lectures that the title character gives, he refers 0:05:52.720 --> 0:05:55.120 to the original Earth and how it no longer exists. 0:05:55.880 --> 0:05:57.479 It may be a reference elsewhere in the in the 0:05:57.520 --> 0:06:00.560 saga as well. But yeah, this episode is kind of like, 0:06:00.600 --> 0:06:03.560 how do we to what extent can is that unavoidable? 0:06:04.560 --> 0:06:07.840 The eventuality of Earth being gone or Earth being just 0:06:08.120 --> 0:06:11.120 there but but nothing that we could live upon, And 0:06:11.240 --> 0:06:14.560 what can we do about especially some of these random 0:06:14.600 --> 0:06:18.680 and short term threats to the habitability of Earth. Now 0:06:18.800 --> 0:06:22.039 one of the long term effects this is not something 0:06:22.040 --> 0:06:25.680 we need to worry about tomorrow or technically in the 0:06:25.720 --> 0:06:29.400 next hundred years, but it is going to be a concern. 0:06:29.440 --> 0:06:31.840 It's probably one of the first things most people think of, right, 0:06:32.200 --> 0:06:35.440 is the death of the Sun. That's right, like the 0:06:35.480 --> 0:06:38.480 Sun just eventually turning into a red giant and swallowing 0:06:38.520 --> 0:06:41.719 the planet Earth. Yeah. Again, I would say, don't don't 0:06:41.839 --> 0:06:44.800 lose any sleep over this, but it does exists as 0:06:44.960 --> 0:06:49.920 the like the late game game ending Doom counter situation totally, 0:06:50.000 --> 0:06:52.480 this is the point at which the game has to end, 0:06:53.400 --> 0:06:55.880 or may have to end. Well, we'll get into some 0:06:55.960 --> 0:07:00.200 of that presently. So I like to think of the 0:07:00.240 --> 0:07:02.960 Sun is kind of a dot com erab business. It's 0:07:03.080 --> 0:07:06.320 running on a huge influx of funding, but destined to 0:07:06.360 --> 0:07:09.920 eventually burn out. Eventually the money is gonna gonna go away, 0:07:09.920 --> 0:07:13.240 Eventually the energy is going to go away. So our 0:07:13.280 --> 0:07:15.960 son has been going strong though as a business, as 0:07:16.000 --> 0:07:18.560 a star, as the center of our solar system for 0:07:18.720 --> 0:07:22.400 four point five billion years, and by most estimates it 0:07:22.440 --> 0:07:25.400 has it has another five billion years left in the tank. 0:07:25.520 --> 0:07:29.280 So it's got a lot of pivoting left to do. Yeah. Well, no, 0:07:29.440 --> 0:07:32.680 well the pivots are key, because the pivots are or 0:07:32.760 --> 0:07:35.360 what what we're gonna have to worry about. So when 0:07:35.400 --> 0:07:38.160 the core runs out of hydrogen fuel, it's going to 0:07:38.240 --> 0:07:41.520 contract under the weight of gravity. Uh So again, think 0:07:41.520 --> 0:07:44.080 of like a bloated business that's suddenly the money is 0:07:44.120 --> 0:07:48.080 not there to support it and it has to downsize. Um, 0:07:48.120 --> 0:07:50.720 this is where the metaphor kind of becomes more difficult 0:07:50.760 --> 0:07:53.800 to engage here, because, uh, some hydrogen infusion is still 0:07:53.800 --> 0:07:56.000 gonna occur in the upper layers at this point, and 0:07:56.120 --> 0:07:59.800 is the depleted core contracts, it heats up and this 0:08:00.000 --> 0:08:02.080 it's up the upper layers of the Sun, causing them 0:08:02.080 --> 0:08:05.280 to expand. As the outer layers expand, the radius of 0:08:05.320 --> 0:08:10.120 the Sun will increase and it will become a red giant. Now, 0:08:10.120 --> 0:08:12.720 the radius of the red giant Sun would be a 0:08:12.760 --> 0:08:15.560 hundred times what it is now, lying just beyond the 0:08:15.600 --> 0:08:19.280 Earth's orbit. Some scientists have estimated that this would vaporize 0:08:19.280 --> 0:08:21.080 our planet, but there's also a good chance that it 0:08:21.120 --> 0:08:24.760 would push Earth in its moon outward after consuming mercury 0:08:24.760 --> 0:08:29.400 and venus. Now, obviously there's there's again nothing to lose 0:08:29.440 --> 0:08:32.520 sleep over here. Um, you know, five billion years, that's 0:08:32.559 --> 0:08:35.080 longer than the Earth has existed, and the span of 0:08:35.080 --> 0:08:38.000 the human species is virtually nothing in that well of time. 0:08:38.520 --> 0:08:40.640 And of course there's a lot that can and will 0:08:40.720 --> 0:08:44.160 happen before the Sun turns into a red giant. Long 0:08:44.200 --> 0:08:46.800 before this happens, say in a mirror one point two 0:08:46.840 --> 0:08:49.440 billion years, the Earth will grow hot enough to boil 0:08:49.480 --> 0:08:52.200 the way our oceans. And then, after all this takes 0:08:52.200 --> 0:08:54.880 place after the red giant phase, in nine point five 0:08:54.920 --> 0:08:57.800 billion years, the Sun will collapse into a white dwarf 0:08:58.200 --> 0:09:02.080 and the remaining dead world will continue to orbit around it. Eventually, 0:09:02.080 --> 0:09:04.720 the white dwarf will go dark, and there'll be this 0:09:04.760 --> 0:09:08.840 inevitable collision between it and another black dwarf, and this 0:09:08.920 --> 0:09:11.640 will blast apart the remnants of our solar system. This 0:09:11.720 --> 0:09:15.440 according to an excellent article in Forbes, of all places, 0:09:15.840 --> 0:09:19.320 even Ethan seagulls how our solar system will end in 0:09:19.400 --> 0:09:22.800 the far future. I actually read the same piece, and Uh, 0:09:22.920 --> 0:09:26.640 Siegell says, when our son was newborn, this is this 0:09:26.679 --> 0:09:29.800 is good to get some perspective on it. It only 0:09:29.840 --> 0:09:34.000 had of the power that it has right now. But 0:09:34.080 --> 0:09:38.040 the properties of planet Earth, the flora, the fauna, the ocean, 0:09:38.120 --> 0:09:40.720 the atmosphere, all of that stuff has allowed us to 0:09:40.840 --> 0:09:44.920 adapt right Also, the astrophysicist Robert Smith, not to be 0:09:44.960 --> 0:09:49.120 confused with the frontman of cure Uh, says even just 0:09:49.280 --> 0:09:53.280 the aging of the Sun will accelerate global warming to 0:09:53.400 --> 0:09:56.920 a point where Earth's water just simply evaporates, as you 0:09:56.960 --> 0:09:59.360 mentioned earlier, so there's not a whole lot we can 0:09:59.440 --> 0:10:02.679 do about that. The atmosphere will be laden with water 0:10:02.760 --> 0:10:05.040 vapor at that point, Uh, And it's going to turn 0:10:05.040 --> 0:10:07.760 out like the water vapor will act like a greenhouse gas, 0:10:07.800 --> 0:10:09.640 which we're obviously going to come back to later. In 0:10:09.640 --> 0:10:12.880 this episode, the oceans will boil dry. But all right, 0:10:12.960 --> 0:10:16.240 let's think really cosmic here for a second. Okay, let's 0:10:16.280 --> 0:10:20.640 like zoom out. Let's pretend like we're Galactus from from 0:10:20.679 --> 0:10:23.840 Fantastic four Comics or something here. Okay, what if we 0:10:23.880 --> 0:10:30.560 could harness comets and asteroids so they gravitationally slingshot past Earth, 0:10:31.040 --> 0:10:34.600 but move us into a wider orbit away from the Sun. 0:10:35.080 --> 0:10:37.960 That might be possible in the future. Um, and I 0:10:38.000 --> 0:10:40.720 believe on the Kardaship scale, that's like one of the 0:10:40.800 --> 0:10:43.400 sort of ladder parts of the scale. Rights, if you 0:10:43.440 --> 0:10:47.640 can harbor harness cosmic entities, well, I mean, first of all, 0:10:47.800 --> 0:10:49.920 if you can harness all the power of the planet, 0:10:49.920 --> 0:10:51.320 and then if you can harness all the power of 0:10:51.320 --> 0:10:54.360 the Solar System. So yeah, just at that level, he 0:10:54.440 --> 0:10:57.679 would consivably have the ability to to move the planet 0:10:57.760 --> 0:11:00.480 around to find a new orbit for it in some 0:11:00.559 --> 0:11:03.520 of the the more extreme cases. You know, I've seen 0:11:03.520 --> 0:11:05.240 it argue that, you know, you could take the planet 0:11:05.240 --> 0:11:08.000 and move it beyond the Solar System. Certainly, when you 0:11:08.000 --> 0:11:11.720 get into those upper levels of K three and K four, Uh, 0:11:11.920 --> 0:11:16.559 you're talking about godlike power, where on one level it 0:11:17.120 --> 0:11:19.000 becomes easy to say, well, of course we could do 0:11:19.040 --> 0:11:20.720 this because of the amount of power that we would have. 0:11:21.000 --> 0:11:23.080 And then on the other you have you have to say, 0:11:23.120 --> 0:11:25.360 what would we be if we had that much power, 0:11:25.360 --> 0:11:28.600 if we had the power to harness uh all the 0:11:28.600 --> 0:11:31.560 power of a solar system or or or you know, 0:11:31.640 --> 0:11:35.280 scales beyond that, then what would what would our values be? 0:11:35.440 --> 0:11:38.160 What would we need? Would we care about moving the Earth? 0:11:38.520 --> 0:11:40.240 We'd just be like, well, let it burn. We've got 0:11:40.280 --> 0:11:43.960 these crazy spaceships now. Well, another theoretical way to move 0:11:44.000 --> 0:11:48.120 the Earth is to build a planetary sunshade. That would 0:11:48.160 --> 0:11:49.840 have a similar effect, and it would move it out 0:11:49.880 --> 0:11:52.640 into a further orbit. But hey, guess what, even if 0:11:52.679 --> 0:11:55.640 we can do that, the red giant phase of the 0:11:55.679 --> 0:11:58.360 sun is it's gonna get earth like. Even if we 0:11:58.400 --> 0:12:01.600 can move it far enough out that we can somehow 0:12:02.320 --> 0:12:06.199 use it to mitigate climate change, for instance, it's it's 0:12:06.200 --> 0:12:08.000 not gonna matter that red giant is eventually going to 0:12:08.040 --> 0:12:11.200 swallow us. Well, I'm not not by all. It depends 0:12:11.200 --> 0:12:14.000 on how far out I guess you move it. Yeah, 0:12:14.040 --> 0:12:18.760 but even if we escape, what's the world look like afterward? 0:12:18.920 --> 0:12:23.640 As we're slouching towards extinction. Okay, so astrobiologist Jack O'Malley 0:12:23.760 --> 0:12:27.480 James of Cornell University actually sketched out a sequence of 0:12:27.520 --> 0:12:30.199 extinctions over the course of four billion years. So here 0:12:30.240 --> 0:12:33.920 we go, all right, at five hundred million years from now, 0:12:33.960 --> 0:12:36.319 from right now, that's when the sun is going to 0:12:36.400 --> 0:12:39.400 start getting hotter and c O two will be sucked 0:12:39.400 --> 0:12:42.080 out of the Earth's atmosphere. That's gonna make all of 0:12:42.080 --> 0:12:46.240 the plants die off because they can't photosynthesize. Following that, 0:12:46.440 --> 0:12:49.360 large vertebrates will go, then the small ones because there's 0:12:49.360 --> 0:12:52.280 no plants for them to eat. Then the only remaining 0:12:52.360 --> 0:12:57.400 animals will be marine invertebrates along with microbes. Maybe some 0:12:57.480 --> 0:13:00.000 insects that can eat dead plants will still be around, 0:13:00.160 --> 0:13:03.959 but mostly the only creature, uh, the only creatures that 0:13:04.000 --> 0:13:05.599 don't need to eat plants are gonna be able to 0:13:05.679 --> 0:13:10.760 survive this. The last non microscopic remaining animals will probably 0:13:10.800 --> 0:13:14.400 be those tube worms around the deep sea hydrothermal vents. 0:13:15.240 --> 0:13:18.320 Then at one billion years out from now, that's when 0:13:18.320 --> 0:13:22.600 the oceans start to boil. Uh. And then if that 0:13:22.679 --> 0:13:25.760 doesn't kill the microbes, the actual boiling of the oceans, 0:13:26.080 --> 0:13:29.040 the CEO two levels eventually will fall so low that 0:13:29.160 --> 0:13:34.160 even microbial photosynthesis will end. Okay, then at seven point 0:13:34.280 --> 0:13:36.880 five billion years out, that's when we're talking about the 0:13:36.880 --> 0:13:41.600 Red Giant engulfing Earth and the Moon. But what if 0:13:42.120 --> 0:13:47.319 Jupiter's moon tighten suddenly became warm enough for life to evolve. 0:13:47.520 --> 0:13:50.679 So maybe that's the next place where there's going to 0:13:50.720 --> 0:13:53.280 be a habitable society. Well, it comes back around to 0:13:53.360 --> 0:13:58.440 the the frequent argument you see from from various astrophysicists 0:13:58.440 --> 0:14:01.439 and futurists, and that's just the the long long term 0:14:01.480 --> 0:14:06.080 survival of the human race depends on us UH expanding 0:14:06.160 --> 0:14:12.240 beyond Earth absolutely. Now, some additional concerns for the future 0:14:12.720 --> 0:14:16.680 in any case of the far future. One is magnetosphere loss. 0:14:16.800 --> 0:14:20.560 So Earth's magnetosphere is essentially a magnetic bubble that protects 0:14:20.600 --> 0:14:24.880 the Earth from charge particles and plasma Earth's solid intercore 0:14:25.080 --> 0:14:29.480 and liquid outer core. This generates the field. Okay, it 0:14:29.600 --> 0:14:33.720 generates the magnetosphere, and according to the dynamo theory, differences 0:14:33.720 --> 0:14:36.920 in temperature and composition in the two core regions drive 0:14:37.200 --> 0:14:42.320 this powerful dynamo UH, emitting Earth's protective electromagnetic field. Now, 0:14:42.360 --> 0:14:45.360 some scientists theorized in about two to three billion years, 0:14:45.800 --> 0:14:49.960 the dynamo MD half, leading to the decay of the magnetosphere. 0:14:50.240 --> 0:14:54.000 And remember again how essential this field is. It's absence 0:14:54.280 --> 0:14:57.840 on planets such as Mars make colonization a challenge. Like 0:14:57.880 --> 0:15:01.320 it's hard to imagine life being being able to to 0:15:01.480 --> 0:15:05.760 really take a firm um hold of a planet that 0:15:05.800 --> 0:15:09.680 does not have a magnetosphere in place to shield life. Yeah, 0:15:09.800 --> 0:15:12.920 protects us from so many of the hazards of space. 0:15:13.080 --> 0:15:16.640 It's one of the key aspects of the Goldilocks principle, 0:15:16.760 --> 0:15:19.200 you know, one of the things that makes this planet 0:15:19.280 --> 0:15:22.080 just right. And it's uh, it can be kind of 0:15:22.080 --> 0:15:24.680 frightening or sobering to think about the fact that this 0:15:24.760 --> 0:15:27.720 is not something that will last forever. But what about 0:15:27.720 --> 0:15:29.760 the Moon. I've seen a lot of people talk about 0:15:29.800 --> 0:15:31.520 the moon is being like, well, if we could go 0:15:31.600 --> 0:15:34.320 anywhere if climate change gets too bad, let's just go 0:15:34.360 --> 0:15:37.680 to the Moon. Well, um, yeah, that well, the Moon 0:15:37.920 --> 0:15:41.600 is probably not a great option for for living on either. Uh. 0:15:41.760 --> 0:15:45.520 But but it does play into another long term concern, 0:15:45.600 --> 0:15:48.200 and that has to do with the perturbation effects. So 0:15:48.760 --> 0:15:53.680 our large moon ensures climate stability by minimizing changes in 0:15:53.760 --> 0:15:57.000 planetary tilt. If our planet didn't have a tilt, it 0:15:57.040 --> 0:16:00.040 wouldn't have seasons. Likewise, a severe tilt would result in 0:16:00.120 --> 0:16:04.040 extreme seasons. As we've discussed on the show before, the 0:16:04.080 --> 0:16:08.320 Moon is drifting away from Earth. Eventually, given you know, 0:16:09.040 --> 0:16:12.280 enough time, it will be just far enough away to 0:16:12.360 --> 0:16:15.720 make a total solar eclipse impossible. Yeah, I've actually got 0:16:15.760 --> 0:16:18.400 some stats on that the Moon is moving away from 0:16:18.520 --> 0:16:23.720 us at three point seven eight centimeters a year. Between 0:16:24.040 --> 0:16:26.720 one point five and four point five billion years from 0:16:26.720 --> 0:16:29.840 now is when it's going to stop stabilizing our tilt. Yeah. 0:16:29.840 --> 0:16:31.760 The so the Moon pulls on the Earth, and the 0:16:31.800 --> 0:16:34.720 Earth orbits the Sun, resulting in a torque that causes 0:16:34.720 --> 0:16:37.440 the Moon to move a little bit farther away from 0:16:37.440 --> 0:16:40.880 the Earth and slow the planet's rotation. Rotation slows by 0:16:40.880 --> 0:16:43.720 one point four milliseconds per century. But in fifty billion 0:16:43.800 --> 0:16:47.200 years time, the Moon will orbit in forties, you know, 0:16:47.640 --> 0:16:50.080 at a rate of forty seven days as opposed to 0:16:50.200 --> 0:16:52.640 the twenty seven point three days we know today, and 0:16:52.680 --> 0:16:55.560 the twenty four hour Earth day will be forty seven 0:16:55.640 --> 0:16:58.240 days long, and the Moon and Earth will then become 0:16:58.280 --> 0:17:01.440 tidally locked as well. Luckily, we've already established that well 0:17:01.480 --> 0:17:04.359 before that fifty billion year mark, the Sun is gonna 0:17:04.400 --> 0:17:07.160 eat both of them, so it doesn't really matter. Yeah, 0:17:07.200 --> 0:17:10.480 and so the idea here is that, uh, once the 0:17:10.520 --> 0:17:14.560 stabilizing of the Earth's tilt stops, the poles are gonna 0:17:14.640 --> 0:17:17.520 tip to a point where like the North and South 0:17:17.560 --> 0:17:19.840 poles are going to be where the equator would have been. 0:17:19.880 --> 0:17:23.320 And this is going to cause obviously extraordinary climactic effects. 0:17:24.040 --> 0:17:25.879 But it goes back to what we were talking about earlier. 0:17:25.880 --> 0:17:28.959 I mean, we have just the right moon for life 0:17:29.000 --> 0:17:31.600 to be able to thrive here on Earth. So how 0:17:31.640 --> 0:17:36.840 does this explain Transformers five? Then? Because in that movie, 0:17:37.000 --> 0:17:40.240 the planet Cybertron just parks itself right next to Earth 0:17:40.440 --> 0:17:44.160 and I think destroys the Moon. So I mean, clearly 0:17:44.280 --> 0:17:46.480 they thought through the science on them. I assume they 0:17:46.480 --> 0:17:54.280 brought um just being silly here. Obviously those don't make 0:17:54.320 --> 0:17:57.760 a like a sense. But when this whole thing happens 0:17:57.760 --> 0:18:00.199 with the tilt, some regions of the planet and it 0:18:00.320 --> 0:18:02.480 will still be protected by the Sun, So it would 0:18:02.520 --> 0:18:05.000 be possible to still live on the planet after this 0:18:05.119 --> 0:18:09.080 perturbation effect. So h What would be bad though, is 0:18:09.119 --> 0:18:12.920 that some parts would dip to below a hundred degrees 0:18:12.960 --> 0:18:15.320 celsius for part of the year. The only thing that 0:18:15.359 --> 0:18:17.920 would be able to survive would be microbes inside these 0:18:17.920 --> 0:18:20.919 cold trap caves. And then even two point two billion 0:18:21.000 --> 0:18:24.840 years after that, those caves then will suddenly become too hot. 0:18:25.680 --> 0:18:28.520 So yeah, it's no win scenario. You have to This 0:18:28.640 --> 0:18:31.960 is when humans have to start living in the big pyramids. 0:18:32.000 --> 0:18:35.760 The last re doubt of William Hope Hodgens The Night Lands. 0:18:35.800 --> 0:18:38.520 Maybe that's what that hidden vault inside the pyramid was 0:18:38.560 --> 0:18:41.560 that they just found recently. It's it's specifically designed for 0:18:41.640 --> 0:18:44.800 when the moon's moon stops affecting her tilt. I do 0:18:44.880 --> 0:18:47.840 recommend any anyone who is interested in sort of uninhabitable 0:18:47.840 --> 0:18:50.320 earth sci fi. William Hope Hodgins The Night Lands is 0:18:51.000 --> 0:18:55.320 fabulous of kind of challenging to read because it depicts 0:18:55.640 --> 0:18:58.080 uh an age in which humans will have to live 0:18:58.080 --> 0:19:01.040 in these artificial structures UH on a dark earth like 0:19:01.080 --> 0:19:04.359 everything else is just cold and dark, but they're I 0:19:04.400 --> 0:19:08.840 believe they're using thermo thermal energy to to maintain themselves. 0:19:08.880 --> 0:19:11.679 In the book, Hodge and stuff is just fascinating, especially 0:19:11.720 --> 0:19:14.280 when you consider the era that he lived and how 0:19:14.359 --> 0:19:16.960 far ahead. He was thinking, why don't we take a 0:19:16.960 --> 0:19:19.520 break and then we come back. We can talk about 0:19:19.520 --> 0:19:22.800 some just random concerns, things that we can't particularly track 0:19:22.960 --> 0:19:27.359 for how they might end life on Earth. Thank, alright, 0:19:27.359 --> 0:19:29.760 we're back. So this first one is is a major threat. 0:19:29.960 --> 0:19:32.760 Uh and it is a proven major threat to life 0:19:32.760 --> 0:19:37.080 on Earth. We're talking about near Earth objects or ane os, 0:19:37.720 --> 0:19:41.280 So impact events are possible factors in three out of 0:19:41.400 --> 0:19:45.240 five major extinction events here on Earth. Space collisions occur 0:19:45.320 --> 0:19:47.840 all the time, and most of them don't make too 0:19:47.880 --> 0:19:50.160 much noise, or at least those that have occurred during 0:19:50.200 --> 0:19:52.560 human history haven't. That's because in space no one can 0:19:52.600 --> 0:19:55.560 hear you scream. Well, of course, the thing is Earth 0:19:55.640 --> 0:19:57.640 is in space too, so we're counting the Earth colliding 0:19:57.680 --> 0:20:01.200 with things, we're accounting the moon called lighting with things, etcetera. 0:20:01.440 --> 0:20:04.439 But even when they do make noise, we've been very lucky. 0:20:04.520 --> 0:20:09.240 For instance, consider Night to Munguska event, which hit a 0:20:09.280 --> 0:20:13.720 sparsely populated corner of Siberia rather than a major population center, 0:20:14.160 --> 0:20:16.720 and it's it's been pointed out that a mere four 0:20:16.840 --> 0:20:20.400 hours of planetary rotation would have placed the bull's eye 0:20:20.520 --> 0:20:24.280 on densely populated St. Petersburg instead, So instead of having 0:20:24.320 --> 0:20:28.359 this just this devastating crater in this blast you know, 0:20:28.600 --> 0:20:31.520 heard over vast distances, instead of it occurring in the 0:20:31.600 --> 0:20:34.920 middle of nowhere, what if it had occurred in in St. Petersburg? 0:20:34.960 --> 0:20:37.320 What have it occurred in a major center of human population. 0:20:37.400 --> 0:20:40.400 And you like to think, like in these big budget 0:20:40.440 --> 0:20:43.280 blockbuster disaster movies that like we'll be able to chart 0:20:43.320 --> 0:20:46.240 the course of these things, will know that when they're coming, 0:20:46.280 --> 0:20:49.959 and we'll evacuate cities. Right, But well, I mean this 0:20:50.000 --> 0:20:51.439 is this is this is where he gets into something 0:20:51.480 --> 0:20:54.959 I've talked about before, Like this is one of those 0:20:55.080 --> 0:20:59.440 one of the few areas where where you can conceivably 0:20:59.520 --> 0:21:03.080 save the world. Um, because the odds are that a 0:21:03.160 --> 0:21:05.960 large INEO will come into play in the future and 0:21:06.080 --> 0:21:09.400 humans will hopefully be in the technological and cultural position 0:21:09.560 --> 0:21:12.720 to identify it, to track it and mitigate the situation. 0:21:12.760 --> 0:21:15.480 There are a number of different um methods that have 0:21:15.560 --> 0:21:19.879 been proposed for deflecting an incoming INEO, and they range 0:21:19.920 --> 0:21:21.480 from you know, blowing it up to just sort of 0:21:21.560 --> 0:21:24.520 nudging it out of the way, to you know, harvesting it, 0:21:24.840 --> 0:21:29.320 et cetera. You send Bruce Willis and Steve BUSHEMI up there, Uh, Peter, 0:21:29.359 --> 0:21:32.560 storm are and problem solved. Well, hopefully, I think we're 0:21:32.560 --> 0:21:35.040 getting to the stage we realize we only need to 0:21:35.040 --> 0:21:39.320 send UM. But yeah, this is one of those few 0:21:39.359 --> 0:21:42.840 areas where the work of NASA and other space agencies 0:21:42.880 --> 0:21:47.280 their work to track ineos and and and eventually mitigate them. 0:21:47.320 --> 0:21:50.200 This is one of the few areas where concentrated human 0:21:50.200 --> 0:21:54.280 efforts can actually save the world. And of particular interest 0:21:54.320 --> 0:21:56.960 here are asteroids that are six point two miles or 0:21:56.960 --> 0:22:01.120 ten kilometers in diameter or larger. The These are extinction 0:22:01.240 --> 0:22:04.240 class ineos. So here's some stats that I found on this. 0:22:04.440 --> 0:22:09.760 A third of those thousand mile wide asteroids that are 0:22:09.840 --> 0:22:16.440 hurtling across Earth's orbital path will eventually strike us. But luckily, 0:22:16.520 --> 0:22:18.600