Will solar sails take us to the stars?

It's nice and quiet. Yeah. You know, these companies like that are trying to get people to come back in not telework. Oh really? Is that a new movement, the non teleworking movement? All I didn't make mouch sense. I'm going backwards back in time. Yeah, you know, I might as well make them drive to work in a horse drawn carriage and wear a suit and tie on for days. Uh. Good to see you, my friend. Thanks, good to see you too. Man. Are we gonna sail through the galaxy together? Yeah?

I've got one intro. So about four years ago, okay, there was an astronomer named johann Kepler. I heard of him, Johannes Kepler, take your pick is the s silent? Who knows? I think Johannes he founded the Kepler effect. Yeah. So he also had this idea that, um, there was a what's called the solar wind, that there was a wind that blew through space, and it was evidenced by the curvature of comets tales. You could see them just kind of bending a little bit, and that was because they

were being blown by the wind. So Kepler, as was pretty much the thinking at the time, during the age of exploration when he lived, UM, he said, maybe we should construct some sales, some mighty sails that can survive in outer space and just sail around the galaxy. That's pretty forward thinking. It is forward thinking. And Kepler was

wrong about the solar wind. There isn't a wind in space, although there is solar wind now, but it's just some ion, positively charged ions that hit the magnetosphere of the Earth and um create the northern and Southern lights. It's not like a warm wind literally blowing through space exactly. Um. But Kepler's suggestion led to just this huge, incredible irony wherein we have figured out now how to sail through space not using wind but using sunlight. And it's been done. Yeah,

it's been It's been proven now several times. Think in two thousand ten Japan did it and uh in two thousand fifteen. A pretty major one is gonna set. Yeah, the biggest one, for sure, it's gonna literally set sail. I think it's square feet. That one is huge. Yeah, it's a I think ten city blocks. No, that was a different one. I'm sorry. Square feet though, was definitely the largest one that will have been put in space.

There was one that was ten square called the Nano sale that was that worked just fine, that NASA launched, was up in orbit for a year and then came back down and they were able to do all sorts of cool stuff with it. And even before then, apparently the the idea of sailing through space, this analogy between space and the oceans, um is not lost on anybody who's into this whole idea and um, even before this, the current incarnation, there were uses of solar sales, like

in the seventies. I think Voyager two UM, which is one of those deep space probes, was having trouble with its attitude it was having attitude problem and it needed an adjustment. So the the controllers down on the ground turned its solar arrays and used UM them like a solar sale to correct its attitude. Worked. UM, and then it worked enough that in the seventies, remember Haley's comment, Okay, well that was six that it came through, and we're going to be the last generation to be able to

see it twice. Probably when's it coming back? I think it was sixty years or sixty years, so let's see. That would be two thousand fifty four. We'll make it.

We'll see. Um. The the there was a whole NASA program that lasted about a year to rendezvous with a solar sale, using a solar sale to rendezvous with Haley's comment, I don't know what they were gonna do when they came upon it, but um, the idea of a solar sale and the fact that a solar sale will work has been proven and known since at least the nineteen seventies, but only recently have we been launching these things and getting them to do what we want, which is travel

through space without the use of rocket fuel. Yeah, because that's a huge thing, man, Rockets use a lot of fuel, and it's a constraint. It is, in fact, the weight of the Space Shuttle, the dearly departed Space Shuttle was fuel. And the way rockets work in general is they expend there, they shoot their payload to get them going, and then

they cruise basically. But that's a lot of payload and a lot of fuel, and but they they're not just constantly like have their foot on the accelerator, you know, because they can't tote around all that fuel. No. Well, even if they did just sit there and have the gas pedal to the metal all the way, eventually they're going to run out of fuel too. So it's a double constraint. You have a finite amount of fuel and

you can't accelerate constantly. Um. Plus there's also a third one too that the solar sale pretty much has over a rocket um it can return to Earth, which is called de orbiting UM. So let's talk about this, like, what do you need to have a solar sale? Like? It's a pretty basic simple it really is, but it's pretty much the future of space travel. We've talked about antimatter spacecraft before, Yeah, that might have been where we mentioned this. Actually definitely touched on this once to put

these two together. If the solar sale is definitely the winner, Um, anti matter spacecraft requires us to be able to produce something that doesn't exist yet, which is in I can't remember, an anti proton maybe yeah, I can't remember. Um, this is like, we've got everything we need right now to do this, so let's do it. What we need continuous force from the sunlight. You need a large mirror that's really thin. We'll get into that, and you need something

to launch it. You can't launch these things from the ground. Um, they do great once you get them up there, but you're still gonna have to launch it into space. Yeah. Even still, it's such a minor constraint. It's it's ridiculous. A scoff at its inclusion. And the reason this works is because light, uh, it releases electromagnetic radiation in the form of protons. And these protons even though they don't

have mass. Photons, what say protons? These photons, even though they're on a mass, they have momentum, and that is that momentum when it hits a solar sale is just like a little wind blowing a sale. It transfers its energy and it's just it's almost the same thing as a wind blowing a sale. Yeah, when you put a bunch of them together, it is very much like that. Especially if you think of wind as little discrete packets of wind, this is little discrete packets of light and

also chuck. When a photon hits a reflective surface, a highly reflective surface, it transfers its momentum twice. The first time when it hits it pushes it along, and then when it pushes off to bounce off to reflect so it transfers momentum twice. So photons hitting a reflective surface in outer space, the vacuum of space where there's no resistance, that's something that you know you can kind of get behind. Yeah,

it's significant. And if you look at an individual photon or even um sunlight as a whole, it doesn't have a lot of it doesn't exert a lot of force. It's something like nine Newton's per square mile. Yeah, like that's the reason they can't take off from the ground. Um. Nine Newton's is what you get from the Sun to the Earth, right, and in an astronomical unit, right nine three million miles, you're gonna get about nine Newton's of force.

That's how much Yeah, by the time they reach this this area, that's how much force there, Which is the reason why you can't take off from the Earth with a solar sale because you need about one point six seven million newtons of force for a liftoff of like a rocket, and they're they're way behind as far as lifting off from the ground, right, and once it's out of space to a rocket is clearly superior for quick acceleration because it can produce like two point one million

newtons of thrust and again sunlight produces nine two point one million compared to nine. But the big advantages again, your solar sale doesn't use any kind of fuel once it's unfurled and deployed, and it can accelerate constantly. And this is the big advantage that it has over rockets. Yeah, well, that flashy rocket might blast off and shoot its payload and go zooming through space. The little solar sale is just kind of going about its way, getting little faster,

getting little faster. And eventually that rocket, though, is gonna go through all its fuel and the little solar sale is going to catch up to it because it constantly has its foot on the gas. As a matter of fact,

there's a really good UM analogy in here. I guess it's not even an analogy, it's some sort of statement maybe that if we launched the Solar Sale right now, it would take about eight years for it to catch up the Voyager one, which is the most distant rocket based or fuel based UM spacecraft in the in the universe. Now we've launched, it's towards the edge of the Solar System right now. Which, by the way, did you know that all of the images you've seen of the swirling

Milky Way galaxy overhead are fake? I didn't know that. We don't have any way to produce that photograph. We've reached the edge of our solar system. We have no way of looking above the entire galaxy. So all of this is what we surmise this. Yeah, but it's never presented that way. You think like, well, it's the that's our photos of the Milky Way. I never thought like, right, that's impossible, Like we're not even sure how many arms

the thing has. Wow. I just think it's a little arrogant too two produce pictures like that and not say this is an artist rendering. This is an artist rendering it probably says that at some point, right, I never noticed that. It's like those fake newspaper articles where you get to the end of it, this is this is an advertisement, right yeah? Um, alright, So we were talking about the it would take eight years to reach the voyager. Yeah, and that's like one of the big which has been

sailing for twenty years. Yeah, and that's one of the b and that that maybe the biggest advantage of a solar sale is deep space exploration because the problem with anything else is gonna eventually gonna run out of fuel. And that's what this one. I think it is set to go deeper into space than anything ever. Yeah, if it makes it, and probably pretty quickly. So like the whole advantage of um of this is that when the solar sales starts to pick up, let's talk about how

fast it moves? Real quick you want to does it? Hall? But and not at first? So it picks up one millimeter per second of movement every second once it starts, So it's moving a millimeter a second at first. That is not fast at all. Um. By comparison, a a rocket moves about fifty six a second something like that. That's right. So it begins very slowly, right, but then it starts to accelerate. There's constant acceleration, and by the end of a day, it'll have reached three kilometers per hour. See,

and it will have already traveled for miles. By the end of twelve days, it will have accelerated to thirty seven hundred kilometers per hour. That's fast. And eventually, chuck um, it's going to start traveling about up to two hundred thousand miles an hour. That's three d thousand kilometers per hour. That's basically you would make it from New York to Los Angeles on the ground in less than a minute.

That's pretty quick. It is quick. But get this. They figured out that if you use ground based light propulsion, which would use a lot of energy um to direct the lasers at this thing, you could get it up to something like eighteen thousand miles per second eight thousand, six hundred miles per second, which is a tenth of the speed of light. And once we do that, we could make it to a nearby star in about twenty years.

That's pretty good. We could make it to outer planets within a couple of weeks, so The potential for this thing is enormous because it's proven it uses no fuel at least if you're using the sun, and it's the technology that could get us into interstellar travel. That's pretty awesome. So what's it made of? Well, the sale itself is key because it's got to be super lightweight and super thin.

You can't just fly a big mirror up there. Um. What NASA is working with today is something called CP one and it is one d times thinner than a sheet of stationary um. But that is crazy. I know. They worked with Milar for a little while, aluminum reinforced miler, which if you've ever seen Milar balloons, like, that's super thin. It's like a foil um and it's a one fourth the thickness of a one ply plastic bag. And that was the Cosmos one that used the Milar sale. But

basically all these sales are are reflective. It's got to be reflective because the photon has to bounce off of it, and it's got to be super lightweight and super thin. And like any sale, the larger the better. Yeah, you know, the more photons you can catch, the more speeds are gonna get. I guess eventually he said, the one that's going up two thousand fifteen is called the solar Sale Demonstrator. It's dubbed the sun Jammer, which is after an Arthur C.

Clark story. Um, and then apparently is where solar sailing was term was coined. Yeah. I love that guy. Yeah, but that's the one that's going up in two thousand fifteen. He was two thousand and one of space outsy right. Um, and it apparently collapses down to something the size of a dishwasher and weighs a hundred and ten pounds. You and I could lift that together, Um, and I could lift that by myself. They Wow. They pack the thing

into a rocket, shoot it up into space. Once it's in space and orbit, it gets kind of shot out a little bit, and then it, I guess inflates. I believe the booms that hold the sales in place are inflatable, which makes them even more lightweight. Yeah. It's almost like a kite. Um. If you imagine in the supports of a kite, we're all just inflatable, and you would just blow it up. Those would those forms would take shape as buttresses, and then the sale would unfurrel and then

then your sun Jamin. Yeah, land Ho Um, you talked about lasers. That is one of the um I guess co fuels, even though it's not a fuel that these things might use. If there aren't enough photons, maybe they can use lasers to continue to power these um but not for launch though, right, or could they use them for launch? I I it looks like they did launch it, son somehow, I think you could. I think it'd just

be slow. Um, But I think that the probably the most immediately usable method would be to launch it into space and then hit it with the laser once it's in space. Right. I also saw microwave beams have been used too. Yeah, there's a whole other kind kind of competing microwave sale. But the problem is they have to be a lot bigger because of the larger wavelength of a microwave. Seems like using all these things in conjunction together it is probably a good way to go. You know, well,

microwave juice, LI laser juice. Why not use whatever you can? But the yeah, the difference between just using sunlight. One of the problems with sunlight is you have to be going away from the sun because that's the way the direction the photons are gonna gonna so yeah, I think about that, and um, they've pointed out where you can go towards the sun, but you have to basically go out and then come back around and use the photons

to slow you down. Um it just seems kind of Yeah, I wonder if any of these are ever gonna be manned them. They could be if we can figure out how to not crush people in eighteen thousand, six hundred miles per second speed. Yeah, I guess that's true, because can you slow these things down? I don't know. That's

a good question. Yeah, I don't know. The other question I had about this that I couldn't find anything on is if these things are a hundreds the thickness of a sheet of stationary and I've seen gravity, so there's a lot of debris space. How are what's keeping the space debris from just punching holes right in it and just tearing it to shreds. Well, I think it's probably stronger than you would think considering how thin it is,

because it's reinforced. But yeah, you're right, Well, there there's a gravity man, and like solid things were just blown to bits. That guy's face did you like that movie? Yeah? I did. Yeah, I didn't. Um. I didn't go into it expecting the best movie ever, like a lot of people did, and like you know, a lot of hype Crank Neil deGrasse Tyson. We should call it angular momentum, not gravity. It's like, this is a blockbuster Hollywood movie. You know, it doesn't have to be absolutely perfect. I

thought it was. I thought it was great. Yeah. And if you're learning your science from Sandra Bullock, yeah you're in trouble. Yeah. Yeah, you should learn it from other people like yellow graphs, dice um. The other thing that I saw that solar sales can be easily used for is de orbiting that space debris. Apparently you can send some stuff up there, have it go into US uh an orbit, capture a bunch of the space debris. I guess,

just basically wrap itself around it and then bring it down. Uh. I think the way that you bring it down cleaning up space is pretty much it's a big deal. Yeah. Uh. And I think the way that you bring solar sales down so easily is because when you don't need fuel to bring them down, um, and you can just angle them in certain way, so that the sunlight pushes them down towards Earth and they burn up. Oh yeah, that's

pretty nifty. It is. So we may be using them just around Earth first, but these are the things that could very easily lead to inner sellar travel within our lifetime. That's pretty cool. We're talking twenty years right now. You take a lot longer than that without this. Yeah, I'm definitely we should follow up in on the Is that the sun Jammer? Yeah? Which is next year now? Because this is our our New Year's Eve episode, isn't it. Yeah?

I think so. Actually nice. So we're already or we're about to be, depending on when you're listening to this or when it comes out, So in just a year or more, the sun Jammer will be doing this thing. Yeah, we should do a follow up on it. My money is on this one. Maglev trains. Yeah, uh, people going without refrigerators, that's the future. Wiping your butt with cloth? All right, you got anything else? I got nothing else? I'd like this one. I think the solar sale Is

is literally the thing of the future. Yeah, I like it too. Man Um. You want to wish everybody a happy New Year. Happy New Year, Everyone be new year. And I'd also like to say a very happy birthday to my sweet wife. That's right, I always forget it's uh what what's the date birthday? Uh? Well, happy birthday, Umi, and happy New Year's everyone, and be safe and uh we sail into the future. If you want to know more about solar sailing, you can type that word in

the search part how stuff works dot com. And since I said search bar, it's time for a message break. Uh now, Chuck, it's time for listener mail. What am I gonna call this? I'm gonna call this from Roanoke, Virginia just because it's easy death metal for moan Oak. Hey, guys, I was listening to the episode Why Does Music Provoke Emotion? Love that episode, by the way, because music has been such an integral part of my life and everything I do.

And it also reminded me of an experience I had recently. Metal music has always been my favorite genre. I know this email? Uh did you read it? I guess id is really connect with it. Anyway, I recently decided to try out the black metal subgenre. I guess he'd previously was into light metal, right, um, so I purchased Dark Thrones Transylvanian hunger, put it in my car CD player and started driving with the music. When the music started,

I got the strangest feeling. It reminded me of Christmas. Well, this seems like the last reaction when we get from such a type of music. I think I figured it out. The music itself makes me think of icy, snowy winters, which I of course associate with the joy of snow

around Christmas as a child. Between this and the relaxing tremorow guitars that were carrying the music, the cool breeze that I felt through the car windows, and the pale moonlight, the whole experience made me feel a happiness that resembled the kind of usually get around Christmas time. I just found it really fascinating. Is something that I found so relaxing, would probably make most listeners want to scream and if

ash and not unlike the vocalist of most of these bands. Uh, It's so true that music can yield a different reaction from everyone or anyway, I just thought you might find it interesting and thanks for the great show that is from Patrick Hagar Hagar in Roanoke, Virginia. I think you see Hagar well I wanted, but it's h a G and not a R. You should change his name to Hagar with a couple of them wounts. Yeah, it's like then you're listening to Transylvanian Nightmare. What was it called? Yeah,

I think that was right, Transylvanian hungar Uh which Manhattan transfer? No, No, that's the opposite of death metal. Um. If you want to let us know about some strange reaction you had, it's something we've discussed right aside from drowsiness, right because we've put a lot of people to sleep. Yeah. I heard Jesse Thorn talking about the other day about what a backhanded compliment that is or how it always makes

them feel bad. It doesn't bother me, no, And it was on Judge John Hodgman, and Hodgeman was like, no, man, people are saying there in a very intimate moment, you were relaxing them into sleep, and that's a compliment. So that's that's how I just to take it. Hodgements guys such a great perspective on things. Jesse, Come on, buddy, lighten up. Uh. Yeah, if you want to tell Jesse to lighten up, or if you want to tell us about some weird reaction you've had, We want to hear

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