ASM129 Are We Going to Mars?

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the multi-planetary species are we going to mars that's what this special episode of ask science mike is all [Music] not understand about talk anyway we got problems he won't stop there but he'll talk and talk and talk until he flew in the face science faith okay so we're going to do just like a special episode asks science mike because i got a lot of email and tweets always the tweets about uh this elon musk spacex announcement regarding um going to mars and what that would take and and how spacex has updated its plans to do so uh so first let's talk about a couple of things one tuesday october 3rd that's tomorrow and probably when most people hear this episode is when the paperback copy of ask science mike is available in retail stores everywhere and online the retail price on the paperback is only 14 bucks and i've seen it online for as little as 10 dollars i know a lot of the listeners of this program are price sensitive and so the 24 dollar hard back book was just out of reach well guess what 14 bucks is a whole lot cheaper than 24. it also includes an all-new discussion guide for group use so if you want to read ask science mike with a group of friends or people at your church or whatever there's a discussion guide built into the book and it was written by an actual professional not me so that you can learn more by going to findinggodinthewaves.com and also i've got a lot of events coming up we are just about sold out uh for the liturgist gathering in boston which is friday october 6th and saturday october 7th so if you've been thinking about it grab your ticket or you won't get to grab a ticket we just added a little more capacity in the liturgist gathering for seattle october 27th and 28th but that one looks like it's going to sell out too so don't wait around grab a ticket of course i'd love to see you october the 11th for an ass science mic live in london october 13th for ask science mike live in birmingham england and uh or october 17th for ask science mike live in edinboro scotland of course i'll be at the rubicon conference october 21st all those are available at asksciencemike.com just click on the events tab okay so that's our announcements now let's talk about this space thing i want you to imagine for just a moment that we built an elevator like you have an office building only this elevator went up all the way out of earth's atmosphere and in fact more than just going out of our atmosphere went went all the way up to where the space station orbits the earth that high and uh you know if you've ever seen footage of someone on the international space station they are weightless when they're on the iss so what do you think would happen if you stepped on this elevator let's call it a space elevator and you hit the top floor marked with an s for space and you rode the elevator all the way up and you're wearing a pressurized suit so it's not going to be a big deal when there's no oxygen at the top of this elevator and you get to the top the doors open up and you step out what do you think would happen i mean you're all the way up as high as the international space station so would you uh would you enjoy the weightlessness of space free from earth's gravity is that what would happen um or would you begin to drop toward the earth like someone who stepped off a diving board would so what's the difference what makes what makes people on the international space station weightless versus feeling the effects of gravity well you'd be surprised to know if you haven't heard this before that gravity is almost as strong up by the international space station as it is on the surface of the earth so if you built an elevator that went all the way to space and stepped off uh once the doors open you'd fall right back down to the surface of our planet so how in the world do satellites and the international space station and the hubble space telescope and all these objects we've put in space stay in orbit well space is not just a matter of going up from the earth's surface it's also a matter of gaining orbital velocity so you've got to be going a bit faster than 17 000 miles per hour to maintain a low earth orbit think about that that's crazy you need more than 24 000 miles per hour to escape the to escape the earth's gravity well and go to the moon or head to mars or head somewhere else in the solar system it's all about orbital velocity now that's kind of counter-intuitive to us living on the earth surface but to do orbital mechanics to orbit something to travel between celestial bodies it's a matter of velocity gravity is still there in low earth orbit basically you have to fall sideways you've got to go fast enough so that your momentum carries you around the earth uh gravity well as opposed to into the earth's gravity well or the center of that gravity well and that's really critical when we think about going to mars because we've got to escape the earth's gravity well go faster than 24 really faster than 25 000 miles per hour to leave the earth orbit to get out of earth's gravity well to have an escape velocity from the earth's gravity well but once we get toward mars we've got to slow down enough to get caught in its orbit and slow down even more if we want to land on mars surface and then once you're there well you've got to figure out how to come back if you're human it's not a big deal when we send robots to mars it's a one-way ticket but people don't want to be stranded on a planet with no liquid water and no no atmosphere to breathe and no no plants to eat no animals to be around right uh humans want to come back which means we need enough fuel this is a big deal with rockets and this is all what this announcement from spacex is about how can we get people to mars and this event on september 29th is elon musk's vision for humanity becoming a multi-planetary species for for our species to live on more than one planet which he sees and many people see myself included as an essential development for humanity and ensuring the survival of our species a second planet makes a wonderful backup for earth you know what if earth got hit by a sufficiently large asteroid to wipe out human life it'd be nice to have some people on mars for example now if you don't know elon musk he founded paypal and later tesla and also a company called spacex which is a private company that builds rockets that go to space which is really cool now there's been companies before that are private that build rockets but they usually do that under direct government supervision but what elon musk does is he builds rockets that have a a different contractual structure and he has private clients and government clients to deliver payloads to orbit he was the first private company or spacex was the first private company to be certified to deliver uh goods and payloads to the international space station and this is a huge deal and so the the the reason elon musk created spacex was specifically to get to mars not just to do resupply missions for the international space station not to go to the moon but to go all the way to mars and at a conference last year elon musk first introduced something called the interplanetary transport system which was a working name its code name was the bfr for the big effing rocket you can imagine what the f stands for but when he built or when he unveiled his design people had a lot of questions first of all it was a massive rocket with 42 engines and a lot of people wondered if that was within our technological engineering capacity to build people wondered what kind of habitat this mars colony would use so he he showed a rocket ship to get to mars but he didn't show what kind of structures and what technology humans would use on mars when they were there [Music] the bfr had a refueling stations launched into orbit which makes a lot of sense if you can get your rocket into orbit and then fill it with fuel you build a gas station in space so that lets you have a lower launch payload this is a big deal currently when we do space travel we have to carry all the fuel with us to go wherever we're going and get back so that's crazy just imagine driving from new york to los angeles in a car but having to take all your gas with you you'd have to pull a big trailer full of gas which would weigh a lot and you have to carry more gas to cover how much the trailer full of gas burns right it's extra weight so we have to do that with rockets and one thing that the its does is let you re fuel an orbit um and lower the overall mass you have to get off the surface of the planet at one time but a lot of people wonder how feasible that is and of course the question is who pays for this who pays for the rocket and once the rocket gets to mars can we really refuel a rocket on mars that's part of elon musk's plan is to use ice and on on the martian surface to create rocket fuel locally which saves a lot of mass you don't have to take your your fuel both ways um but that's not really helpful if we can't actually make rocket fuel there it's a big gamble to get there uh imagine getting to mars with this this fuel refinery and finding out it doesn't work on mars for one reason or another that would be a real bummer for those colonists or those explorers so there's a lot of questions there and so this september 29th event was about adding more specificity um digging deeper into the idea of how space x could get humanity toward mars now all of this comes at a critical time for human space travel this bfr is meant to solve really significant problems with modern space travel pretty much all the current rocket designs the united states and other countries use are designed either to get a significant of mass to low earth orbit or smaller payloads into deep space we don't have a rocket today the united states or any other country that could take humans and the things humans need all the way to mars the biggest rocket ever made the largest rocket ever made was the saturn v that was part of the apollo program that took us to the moon and we haven't built anything nearly that large with nearly that much rocket thrust since the saturn v now there's a project called the space launch system which is a rocket that uses the engines from the space shuttle but that's going to be really expensive it's been delayed a lot it's looking like it could cost billions of dollars per launch and a lot of people in the space exploration and scientific communities are very skeptical about the space launch system and so spacex has come in and they want to build a rocket even bigger than the saturn v and to their credit it is a really innovative design uh spacex wants to consolidate all their existing rockets one's called the falcon another is called the falcon heavy they have a capsule called dragon and they want to roll in all their future development into the bfr platform this big effing rocket with this spaceship that can seat like a hundred people attached to it and spacex reasoning is the bfr would be a hundred percent reusable and reusing rockets lowers the cost imagine how much an airplane ticket would cost if you had to throw out the airplane after every flight very few people would buy airplane tickets right the cost of airplanes are amortized over the life cycle of the airplane which means tickets can be more affordable the same way if you reuse rockets going to space costs less the fuel for a rocket is not the major cost for getting into space the rocket itself is the major cost so the bfr would be reusable and it would have a really powerful lift capacity it could take 150 tons into low worth orbit and potentially could take 100 people to mars so this is this is much much much greater carrying capacity than anything else on the drawing board uh in the world today this the space launch system is not going to get anywhere near 100 people at a time into deep space it's more like four to six right so this is a big jump but spacex thinks by building the bfr they could take a lot of satellites into orbit at the same time they could uh take significant mass to the moon at one time to help establish a base there and lower the overall cost they're still using the in-orbit fueling to do that but now they've reduced the diameter of the bfr and the current plans to a size that would work in their existing facilities and factories where they build rockets and they've cut the engines from 42 to 31 so it's a smaller rocket but still the biggest rocket humanity has ever built if it gets made now how big is that well right now it looks like the bfr with its corresponding i don't even want to call it a capsule it's it's much bigger than a capsule with its corresponding spaceship um would have almost the internal volume of the international space station which is nearly the size of a football field now that's deceptive that includes all the solar panels so it's the size of a series of tubes laid out on a football field but still at significant capacity and and really really profound uh the idea i mean it as somebody who's followed space travel their whole life it's difficult for me to envision a spacecraft that could carry 100 people or 30 people in a lot of provisions [Music] but the the idea is if you build this rocket it's really usable you start taking a lot more payloads into space you lower the cost of space travel that way you bring the moon within to reach because you can get so much mass there at one time that it would be attractive to private companies and to governments to buy space on spacex rockets because they'd be the only game in town with this kind of lift capacity and theoretically with that low a cost because of the lift capacity and the reusability and out of that there comes some pretty wild ideas a moon base is one um they also mentioned the idea of 30 minute flights anywhere in the world so basically launching people into an orbit uh but not an orbit that circles the earth a ballistic trajectory out of the atmosphere back down so you could go from los angeles to beijing in 30 minutes you could go from you know new york to tokyo in 30 minutes that's wild um and and they said they thought they might be they'll sell tickets that were comparable to economy tickets today i'm really skeptical of that i don't think you're going to be able to reuse the rocket platform nearly as often as you can reuse airplanes i just don't think that's possible so i don't think you'll get the cost that low plus i'm not sure a lot of people would actually take a 30 minute space flight to another point on the earth's surface the acceleration is going to be brutal uh astronauts train and train and train for this and i just don't know that normal people have the fitness level and people will then be weightless for a few moments which means they get really sick during that time i mean i would definitely do it but i think a lot of people would be cautious to take a 30 minute flight across the planet that involves a short trip into space um and and elon musk thinks that this approach could have uh the bfr taking cargo to mars in 2022 and humans on the martian surface by 2024 i think this is incredibly optimistic i mean i think it's i think it's great i'd love to see it happen but i think the timetable's pretty unrealistic i also think i've heard somewhere before this idea of very high capacity spacecraft uh justifying its cost with a very fast launch tempo and that was the space shuttle i mean the space shuttle was incredible but it was so expensive to operate because it was designed for an unrealistic frequency of usage and i worry that what spacex is doing now is repeating that kind of a historic mistake that the space shuttle program made only on a larger scale i'd love to be wrong about that don't get me wrong i'm a huge fan of spacex i love what they're doing for space travel uh i am deeply concerned about the space launch system um but i worry there there's some pretty pretty rose-colored glasses viewing this whole plan right now and i i know there's smart people at spacex doing greater feasibility testing um but i would hate for an all-in on the bfr and taking the focus away from the very successful falcon platform and the potentially successful falcon heavy platform um to end up being spacex spacex's undoing this this is a big bet this is like an all-in bet on a a wild idea a hundred people at a time headed towards the martian surface on the b f r [Music] okay thank you andrew golucky for pre-production greg nordine for production and sound design my patrons for supporting the program and picking the questions and jeb botiford for the amazing ask science mic theme song i'd love to see on the road the next couple of weeks because i will be out a lot and if not i'll just talk to you here in podcast land one week from today see you later