A Problem Squared - 039 = Many Ways to Replace Lights and Trebuchets Shooting Space Flights (live at Bluedot Festival)

Episode Date: August 1, 2022

In this very special episode, live from Blue Dot Festival...   * How many astronauts does it take to change a light bulb?   * What is the most environmentally friendly way to launch an object into space?   * And APS are live for the first time at Blue Dot Festival!    A huge thank you all the contributors that helped make this episode happen;   To Professor Steven Lockley from Harvard. You can find more about his contributions to sleep in space here: https://www.sciencedirect.com/science/article/abs/pii/S0094576512001336   If you want to find out about Circadian Rhythms on Earth, have a listen to Episode 026: ‘Sliding on Snow and Skipping on Sleep’.   To Trent Burton from Cosmic Shambles who helped us get in touch with Tim Peak. You can listen to their incredible selection of podcasts here: https://cosmicshambles.com/podcasts/   And of course, to Sarah Bennetto for booking us! You can find her on Twitter here, she's very funny:  https://twitter.com/sarahbennetto?s=20&t=mf8AoKcmvUXVbHw2YQAoQA   As always, if you've got a problem or a solution, hit us up on aproblemsquared.com.   And if you want want even more from A Problem Squared (and who doesn't) find us on Twitter and Instagram.  

This is this is now the show. So, this early, that excited is bordering on patronizing, but thank you. Humans of Blue Dot. I'm here to introduce, you may know her from ITV's Makeaway Takeaway. If you're a child, if you're an adult, you may know her from her stand-up on all of Jonathan Ross's programs. And if you're an old person, you will know her from the 23 bus to Camden. Please put your hands together for Becca. Thank you. And next to me is my co-host. If you are an older person,

you might know him from Radio 4 or his number one bestseller book, Humble Pie. If you're around mid-age, you might know him from his very successful YouTube channels, Stand Up Maths and Numberphile. That's very fair.

And if you're a young person, this is Matt Parker. I'm not on TikTok. I like the way the audience scaled their enthusiasm like that was a survey. Yeah, yeah, yeah. I appreciate that precision in applauding. We are going to get on very well here. And we are the aristocrats. That's not...

We were right. That didn't work. Oh, no, no, no. You were right. And I heard the comedians backstage laughing. OK, yeah, that's... My work here is done. This is the show, A Problem Squared. So it's a podcast where listeners send us their problems and we solve them.

We try to solve them. Mainly solve them. We give it a go. On this episode... I'll be finding out how many astronauts does it take to screw in a light bulb. I will be looking at the most environmentally friendly way to launch something into space. And if we have time, there will be some any other business. Okay, so we get sent in problems from people all around the world. And this is Damien used the problem posing page on problemsquared.com to say greetings

from Germany. Everyone is making the joke about how many so andand-so do you need to change a light bulb, but no one is asking it for real. That German story is really checking out, isn't it? But I wonder what it is. Are there places where you can't change a light bulb as one person because of its location or because of the shape of the bulb? What about spacecrafts like the ISS?

Does a single person change the shape of the bulb? What about spacecrafts like the ISS? Does a single person change the light bulb on it? I am really tuned for what you may find out. There you are, from Damien, who is really tuned. Is that what the kids say these days? It should be. Yeah. I love it. So, Beck, Damien's really tuned.

How many astronauts does it take to change a light bulb? It should be. Yeah. I love it. So, Beck, Damien's really tuned. Uh-huh. How many astronauts does it take to change a light bulb? Okay, so first I was thinking about it. It's a good question, because you'd think maybe, like, is it two, where one astronaut holds it and the other astronaut spins the other one around? And then I was like, oh, maybe it's not in space. Maybe it's when they're on ground, in which case it's one astronaut, but they need one small step later. These are my people. You were here all along. Who would have thought

a nerd festival where people like puns? And so I looked it up, I looked into it, and I thought, right, there's got to be something somewhere. And I found out that in 2016, they started changing all the fluorescent lights on the International Space Station for LED panels. So I contacted the principal investigator of the experiment they are currently carrying out. It's to find out the effects of lighting on astronauts. And I contacted Professor Stephen Lockley from Harvard. Oh, wow.

I mean, if you're not familiar with our podcast, this is the standard level of research we do. That kind of straight to Harvard, get the expert, and they give you the answer? No. Oh. No, no they give you the answer? No. Oh. No, no. Also on brand for the podcast. Very on brand. Yeah. So Professor Lockley confirmed that the lights have been and are currently still being changed over from fluorescent to LEDs.

Wait, from tubes to panels? Yes. Neither of those are bulbs? Wait, from tubes to panels? Yes. Neither of those are bulbs? Yeah. There aren't really any light bulbs on the ISS.

So I think we're going to have to take liberties to answer this question. Okay, light. And just accept that most light bulbs these days aren't light bulbs. Yeah. So they came back. They didn't have the answer. And I realized I'm going to have to look in further. We need someone on the ground. Not on the ground.

We need an astronaut who is on the ISS to do this. And so obviously we each know a lot of astronauts. Oh, so many. My contacts. Nothing but astronauts. Phone up your favorite astronaut, should we phone up my favourite astronaut? But then we realised we really need someone who was there for the handover. The problem is when you try and text them, the reception is awful.

It's terrible. You know, you have to be on a special authorised list to be able to email the ISS. Is that so? Yeah. Not a joke. Just a fact I thought of right then. So, anyway, did you approach an astronaut? Yes, I did.

I reached out to Tim Peake. Tim Peake was on the ISS in 2016 when they were being changed over. I'm very proud of myself, yeah. And when I say that I reached out to Tim Peake, I mean that I reached out to Trent, who is the producer of another podcast called Cosmic Shambles with Robin Ince. That's right, I used another podcast

to help me answer our podcast problem. But he's got Tim's phone number. He does have Tim's phone number. So I reached out to him, sent him the questions, and while I waited for the answer, I thought I'd look into the rest of the problem. That's a good point, actually, because Damien did say other places

where light bulbs are difficult to get to, like lighthouses and that kind of thing. Yes, yeah. And lighthouses, you would think, might be quite tricky. They're not. In Florida, there is a lighthouse that has an automated system that changes its light bulb

itself. So the answer to that one is zero people. It takes zero people to change a lighthouse light. It's good to establish a lower bound. But then I was like, well, different lighthouses, different systems. So I contacted

the Splitpoint Lighthouse. Yeah, one I'm very interested in. It's a very specific lighthouse. It's very special and dear to my heart. It's near and dear to you. I think quite a few people here will be familiar with it. What I'm going to do is I'm going to sing something and if you recognize it I want you to sing the response. Okay, ready? Have you ever, ever felt like this? Have strange things happened and you go in that way?

Yes, correct! I got in contact with the lighthouse from Round the Twist and said, how many people does it take to change your light bulb? And it turns out that in 2015, they went from 1,000-watt light bulbs to... Guess what they changed them to? LEDs. LEDs, correct! They went to LEDs, and it took two people. Two people to change the fitting. So there you LEDs and it took two people. Oh.

Two people to change the fitting. So there you go. I was quite proud of that. That's so good. It's such a comprehensive... But what about like a modern version of... You know, like those aerial towers with the lights? Oh, that stop aircraft flying into...

Yeah, yeah, yeah. There's like a modern lighthouse. Like a lighthouse stops ships from going into land. Yeah. But the lights on top of aerial towers, they just stop aircraft from flying into themselves. They really kind of create and solve their own problem there. Yeah. We should not have them.

Just get rid of them. Yeah. Don't need them. Yeah, those things are like 2,000 feet in the sky. Right. I looked into that as well. So I did find out how many people it takes to change that. Can we do

it properly oh yeah okay we'll do it properly yeah hey Bec yes how many people does it take to change the light bulb at the top of an aerial tower two oh one to climb to the top of the tower and the other to stay on the ground and turn off the electricity briefly now what it lacks in humor it makes up for in accuracy you gotta go there yeah i don't who how do you choose do they take turns yeah they like flip a coin off you go no obviously the person who climbs the tower that is something that they particularly want to do and in fact i found there was someone in the states he gets paid twenty thousand dollars each time he changes a light bulb.

Which means he only does it twice a year. I've watched the videos. You can find them. You can find videos of people changing light bulbs on top of these towers. After watching the video, I agree. They should be getting paid that much. That is the correct amount.

Absolutely terrifying. Then obviously other towers have lights as well. The Eiffel Tower has 20,000 tiny light bulbs. Now, they don't worry too much about those ones. Oh. But who's going to notice? Yeah. There's tourists there going, wait a minute.

One, two, three. Hang on. Zero. Zero. But there are 425 large Golden Globe spotlights on there that have to be cleaned and changed every year. And that takes 43 technicians. Wow.

Yeah. And they're like on staff. They're what? They're like, that's their job. They're employed all year round. Yeah. Oh, wow. Yeah, that's them.

I thought he had a punchline, but no. You're very excited by that. That was me. I just wish they could fire one, and then you'd have 42, and it would feel correct. Oh, I wanted to know what the largest light bulb would be. Oh. Like, how many people would it take to change the world's largest light bulb?

So I looked it up, and it turns out it's very hard to find out what the world's largest light bulb is, because Guinness World Records are yet to recognize it as a category i know now google will have keeping it in the dark they are keeping it in i see what you did there or did i see it i don't know the lights were off i love playing the game of what did they plan and what did they not plan. A lot of it not planned. Google, how do you think that the largest light bulb in the world

is at the top of the Thomas A. Edison Memorial Tower in Menlo Park, New Jersey? It's not. So Edison is taking the claim for someone else's achievement. Very classic. Classic. And a light bulb. Bit on the nose there, Edison.

Someone booed, and I love that. Someone is just like, I'm sick of this cancel culture. What Swan invented was not technically a light bulb. Yeah, well, the one on top of the tower is 14 feet high, which is pretty big, and that is, like all the other light bulbs we've talked about, not technically a light bulb. It is a large replica bulb with some headlights in it,

allegedly, from what I found. replica bulb with some headlights in it, allegedly, from what I found. Last year, there was a 17-foot tall light bulb created as part of an art installation in Tulsa, Oklahoma. I don't want to be the mask guy, but that is bigger. It is bigger. So I contacted the artist, because that's how far I go into these things, Andrew Romero Tirado, and said, right, what did it take to change it? Now, first of all, it took Andrew and someone called Niels Davis, took them two years to create the light bulb. And then to install it, it took about 50 people. Wait, there's only one, though?

Only one light bulb? If you install it, that's fine, but you need a second one to change it. It's a good point. Am I wrong? You're not just going to pop down to Sainsbury's and pick up a spare one, are you? No, no, no. Your trolley would be huge! And can you use the same 50 people?

The world's largest trolley! Sorry, I got excited. Maybe the same 50 people, or is it got excited. Maybe the same 50 people or is it a distinct skill set to remove it compared to installing the new one? Oh yeah, so it's at least 50 people that you need to change it. Now again, like many of the other light bulbs, this one, what is used to illuminate it from the inside is, can you guess? LEDs. LEDs, yes, that's right, it's LEDs. And I said, well, what would happen if you need to change that at any point?

And they thought about that. Niels and Andrew had thought about that. They had created a hatch in the light bulb skin so you can climb in with a little platform and change the LEDs. So it turns out it takes one person to change the world's largest light bulb. That's because it's a walk-in bulb. You'd want a second person making sure no one walks by and goes, what is that open clink?

Oh, yeah. Because then it just becomes like a mime installation. That's a whole new art installation, isn't it? Man, get stuck in light bulb. Oh, it'd be like if you had an idea so big it took over you. How do I get out of this thought process? I forgot where we were.

No, yeah. Oh, the original problem. Our original problem. Oh yes, ISS. Because Damien did specifically request the ISS. Yes. So, I did eventually hear back from Tim Peake. You got the answer? I have the email here.

I wanted to read it out. Oh, my goodness. I'm very excited. Yeah, yeah, yeah. Yeah, so the first thing Tim Peake said in answer to the question was, not a light bulb. Thank you. Yeah, so I not a light bulb. Thank you. Yeah, so I think we have to agree with that.

Tim Peake said, but I had to change an entire light strip. We call them GLA, that's General Luminaire Assemblies. Such an astronaut. Nah, it's a GLA. And if it gets too hot, we call it a flaming glah. I will not rescind that. I'm going to play in

the groin from your previous pun over that one. Yeah. I like general luminaire assemblies. That's good. Their new stuff is not as good as their old stuff. They're on tomorrow night? They're on tomorrow night? They're on tomorrow night. So it took about half an hour using an Allen key, which NASA

call a hex key or a hex head, which is amazing. I don't know, I didn't ask why. It's the people in geometry. You're either a hex head. Yeah, I'm such a hex head. Oh, yeah. I love geometry.

Oh, you're really into witchcraft. These guys are leaving because they're penta-faces. Oh, hexes. Too many hex heads. So to remove, sorry, they use an Allen key or a hex head to remove the unit, disconnect the old, and reconnect the new electrical connectors, then reinstall the new unit. So about half an hour, nice and easy. And then Tim signed it off with a little smiley face. And then I realized that I had forgotten to ask the original

question, which was how many of you did it take? And so I texted Trent, and I said, oh, my goodness, I didn't actually send you the original question. We've been waiting all this time. I finally got an answer. What an idiot. And then within minutes, he replied and said, I've just texted Tim, and he said, one. So... Matt?

To answer the question, it takes one astronaut to change a light bulb, in quotation marks, as long as they've got half an hour and a hex head. So if we solve a problem, sometimes we go back to the problemer, problemee, to see if we solved their problem. Sometimes we just declare it done. So I suspect

with that maybe declare it done. And we give it a ding. We give it a ding. So I'm going to count down from three on the implied zero. If you think that was solved, give us a ding. Three, two, one. Ding!

We did it! And that is my problem. That is the one that I have solved. Thank you. This next problem is from Andre. Andre says, How big should my trebuchet be? That is a great start. We answer a lot of practical problems like this.

It suggests that right now it's not big enough. Not big enough. Never is. I feel like this is a private email. How big should my trebuchet be if I wanted to use it to throw projectiles faster than the speed of sound? Forget about the material problems here. Assume that the machine itself would be able to cope. That's very handy. It's very handy.

How far would it shoot? Assume ideal situation with no drag. Oh, that's a shame. RuPaul will be sad. Could we shoot into space? Would this trebuchet be the first environmentally friendly space source? Force, I'm going to say that again. Space source is what I have on my space burgers. Would this trebuchet be the first environmentally friendly space force?

I looked into it. Good. Otherwise, we would just end here. Otherwise, the whole premise of the show unravels. Yeah. Okay, so we traditionally launch things into space using a propulsion method. So you launch a rocket, you put all the energy on the rocket, and then you burn it as it goes up. The other option is like a ballistic launch. Like when you play golf. Yeah. When one plays golf. And you hit the ball, that's a ballistic launch.

Because all the energy, you whack it with all the energy, and then there's no further acceleration. You ballistic it off. Oh, so it's not named after the fact that it's a ball. Ballistic. Ballistic, yeah. Yes. Oh, look at it.

It's so spherical. It's almost ballistic. That. Oh, look at it. It's so spherical. It's almost ballistic. That's where the word came from. So parents, explain that to your children afterwards. Whereas if you get a balloon and let go and it farts around the room, that's balloonistic. Yeah, there you go. No, that's propulsion, right?

Because it's constantly... Got it. So the question here is can we put things in space, environmentally friendly, by just giving a big whack? And when we do that, you want to get a lot of energy concentrated and release it all at once. So like a rifle,

that's like a chemical potential energy. Or like giving a child loads of sweets. Yep. Or you can do like... Oh, not a catapult. Loads of sugar. Boom. Yep. Or you can do like a... Oh, not a catapult. Make that very clear. Because a catapult would be like elastic potential energy

when you pull it back. And you go... Right? Because you're bending it. Like a bow and arrow. You're storing energy in some material by distorting it. And then betwang. Oh, okay.

All right. So like if I was flicking a pea with a spoon. Yeah. Cool. Oh, okay. All right, so like if I was flicking a pea with a spoon. Yeah. Cool. It's ballistic, but a trebuchet, you store the energy using gravitational potential energy, and then you release that to launch something. So if you hold a heavy thing up,

you're storing energy by nature of if you stop holding it, if you let go, it'll accelerate down until it hits something. Right. And if it can bounce, so the potential energy, you let go, it accelerates down, bounces, and ignoring losses, comes back up to roughly the same height. Okay. If you drop onto a seesaw, and instead of it coming back up, it goes and stops, and it launches something with half the mass that would go twice as high.

Oh. You're thinking, ah, onto a winner here. So big thing. Yeah. Or heavy thing. Yeah. Means. Small thing.

Further small thing. Got it. Three times the mass. The small thing is like a third. Boom. Three times as high. Love it. Yeah.

So you keep getting bigger and bigger thing. Uh-huh. And then you transfer its potential energy into a smaller thing. Off it goes. And then you transfer its potential energy into a smaller thing. Off it goes. Now, eventually, if you go high enough, there's less gravity due to the Earth because you're further away from it. Oh, yeah.

So what you've got to do is launch something fast enough that it gets out of the gravitational field before the field can slow it down. Got it. And to do that, you've just got to launch it at roughly 11,000 meters a second. Oh, easy. 11 meters a second. Oh, easy. 11 kilometers a second. Sure. Now, at this point, we accidentally scoop up the rest of the problem because they said, can you launch something at the speed of sound? And that is faster than the speed of sound.

Oh, what's the speed of sound? Speed of sound. So we call the speed of sound Mach 1. If you go twice the speed of sound. Not Mark 0, Matt? Mark 2. What? Not Mark 0?

We're both going Mark 0 right now. Oh, that's true. That is true. There we go. Mark 1. There's a big boom. The Mark Warburg. Escape velocity for the Earth, ignoring the atmosphere, as I do.

Mark 32. Wow. So you're going 32 times the speed of sound in air, but there's no air, because we got rid of that for convenience sake. Boom. And then you get something into space. So all you've got to do is get a trebuchet

and can launch something at mark 32. Job's done. You're in business. Right. Easy. And actually, I think the reason they asked this was there's this whole kind of in business. Yeah. Great. Easy. And actually, I think the reason they asked this was there's this whole kind of meme thing about trebuchets.

I don't know, young people find it hilarious that a trebuchet can launch something 90 kilos, 300 meters. I don't know why. It's a young person thing. It is quite funny. There's memes like, me when I weigh 90 kilos and need to go 300 meters in a picture of a trebuchet. It's memes like me when I weigh 90 kilos and need to go 300 metres in a picture of a trebuchet. It's very funny.

When you say kids, who are you talking about? Kids from roughly 12 years ago. So that's why we tweeted, because we thought it would be kind of cool to show you a trebuchet to explain how it works. Yeah, if anyone follows us on Twitter. But the thing is, we tweeted from our own accounts, not from the Problem Squared account. Oh, yeah. Which meant that separately, we tweeted from our own accounts, not from the Problem Squared account. Oh, yeah.

Which meant that separately, we both started tweeting about, does anyone have a trebuchet? Quick. And they're like, you guys had a falling out? Yeah. Which is just a trend. Yeah. We tried to get the hashtag going. It wasn't working.

So, yeah. So, we tweeted, does anyone have a trebuchet? A lot of people are like, oh, I've got one, but it weighs 90 kilos and it's 300 meters away. Very funny. Have you got a second one? Second only to people saying that's a bit of a long shot. Which I laughed like that the first time I read it. After about the 70th time.

We were good. We were good. Yeah, yeah. So we haven't got one. This is before we asked health and safety at Blue Dot if we could bring a trebuchet.

So according to our risk assessment, there will be no trebuchets involved. Yep. According to the risk assessment, definitely no trebuchets. Because a trebuchet are coming on search. It's basically

because you could just use like a seesaw, but it's not a very efficient way to get all the potential energy out of the falling thing into the smaller thing. So a trebuchet is just a very complicated mechanism to make sure you capture as much energy from the big falling thing and transfer it into the small thing. So I actually brought a prop, not a trebuchet. Not a trebuchet. On our risk assessment, it is a kinetic energy demonstration device.

So, okay, so over here, oh, here it is. Now, for the people in the live audience who are watching this, I have just walked back onto the stage holding a perfectly normal broom with a few minor additions. Number one, I have attached two five kilogram weights to the bottom of the broom and that's this is the heavy end of the seesaw. So if we were to balance this on, I don't know, the other broom that's been badly gaffer taped and cable tied to it, as outlined in our risk assessment. And this could be like our fulcrum, like this is where we balance the seesaw, right? And so this is the very basic principle of a trebuchet.

And so actually, oh, look at that. Also, part of this is to, Matt just wants to show you that he can hold two five kilo weights with one arm. People down the front could tell I was struggling. So, okay, so this is... Don't look so nervous! We haven't loaded it... yet.

So this is the basic principle, right? You put a light thing here, you put a heavy thing there, and now when the heavy thing goes down in the gravitational field, patwang, light thing gets launched. And we're like, well, what is the traditional thing to launch into an audience? T-shirts. So, Beck, we organized... Because we didn't have a Problem Squared merch.

So we organized some merch. Yes, we organized some merch, which then did not get delivered in time. Sorry. I guarantee it'll arrive tomorrow. So I've made some merch. So we've got some T-shirts here. We've got a blue dot T-shirt.

That was a blue dot T-shirt. Was a blue dot. Now it's a problem squared T-shirt. As you can see, I've written in Sharpie, a problem squared. And then we've both signed it. And then just to make sure see I've written in sharpie a problem squared and then we've both signed it and just to make sure I have written on the back name another podcast which launches its merch by a trebuchet I'll wait but I have written wait W E I G H T so we've got two blue Dot t-shirts and then one of your Numberphile t-shirts.

We need to face that to become a problem squared merch. We did actually set up a T-Mill website and everything and order them. And that was originally a mock-up temp product. Not with a Blue Dot on it. No, no, no. I'll wait one. But the moment someone orders it, it'll be a real product. Only you have the power to make its dreams come true. Okay, I've now attached a sling to the back of the thing.

So again, this is another way to try and maximize the amount of energy we're gonna get from it. So what you actually do is you load, or you pre... Oh, look at that. That's for maximum impact. That's not maximum impact. That's not in the risk assessment. Okay. But what is in the risk assessment is me verbally warning you, we're going to launch this at you.

If it comes towards you, please catch it. Or if the person behind you is not paying attention, duck. Be very funny. Okay. So, to answer the question, as you can see, there's a lot of variables here and the whole thing is a super super messy Complicated system and we'll tweet there's a nice link to a simulator online where you can change all the variables and see what happens I just worked it out for an idealized Trebuchet then you're getting all the energies from the master dropping and you drop the you drop the mass one metre, and you want to launch this 150-gram T-shirt into space.

You need a mere 940 tonnes of counterweight, a metre off the ground. And you're going to carry that with one arm, Matt? That I might use two and roll my sleeves up. You drop that a meter, this will then, okay, it'll blow everyone's eardrums out as it passes. Oh, there's no air, we're safe. Risk assessment. This will then be launched at 11,000 meters per second into space. I don't know if this is the kind of spacecraft people had in mind when they posed the problem.

We might be able to get Space Force into space, but once they're up there, we can clothe them. Yeah, that's right. There's a lot of astronauts floating around without shirts. Oh, my gosh. I would Google that. Okay. Are we going to do it? Are we going to do it? Oh my gosh, I would Google that. Okay

We're gonna do it? We're gonna do it? Yeah, you're gonna do a t-shirt minus countdown? Thank you, thank you. Excellent, excellent work, okay. Okay, can everyone over here get ready? Okay. Yeah, if anyone's wondering I have put the neon tape around these so you can see them before they hit you right in the face. I like the fact people literally outside the tent are getting ready to catch it. That is very, very optimistic. And if we all play along, people listening afterwards will never know how far this way –

I'm going to say that the people in the first couple of rows are looking far too relaxed. Do you? T-shirt minus five, four, three, two, one. Yeah! CHEERING AND APPLAUSE And for people listening along, that went further than I could have possibly just thrown it. Oh, yeah.

That landed in the next tent. I think we'll be charged for the hole that left at the back of the tent. Yeah. Groove Armada caught it. Shall we? Shall we, uh... This is literally my T-shirt. Yeah.

I brought to wear, so... I haven't worn it yet, it's clean. OK, here we go. Five. Yep. Four. Three. Two. One. Okay, here we go. Five, four, three, two, one. Oh! Can I just say that you caught that in the coolest way possible.

It skipped like a rock going across a pond with everyone tussling over it and then the person over there just went... LAUGHTER Like someone at a wedding who's already married catching the bouquet. I've already got one of these, thank you. I've already got one of Matt's T-shirts. They get trebuchet text.

I just want to address one thing that was in the original set-up for this problem. Is this an environmentally way to launch things into space? Oh, yeah. And the problem is, how do you get the mass lifted up? Because as all these things, the question is, where does the energy come from to then do... Oh, right.

..the carbon-neutral bit? Because you're having to hold up the weight. So if we had to lift up 940 tons. With one arm. With one arm. Like if you do that with a diesel engine, you're right back where you started. Yeah. So, I mean, I guess it could be used to launch things that don't mind being accelerated to 11,000 meters per second at short notice.

But you need to be somehow be able to power it in an environmentally friendly fashion. And then we've solved it. Yeah, that's what we need. Or just, you know, a really high ledge. We'll go to the Grand Canyon. Oh, just fine rocks that are already elevated. Find rocks that are already there. That are just hanging there, like the van in Italian Job.

Just ready to go. And then we're done. Oh, your rocket's powered. Found energy. Yeah. It's free-range energy. It roams wild. I've answered it.

Done. All right. Now, if this works, I believe a ding is in order, if I may be so bold. Okay. I feel like I'm just going to... You know what? Does anyone desperately want this T-shirt? Put your hand... There's a density of you over there. Does anyone desperately want this t-shirt?

There's a density of you over there. The people at the back, though. How much do you really want it that you're still there? I feel like I deeply want to change a variable. Well, I mean, there are heavier weights backstage. There are heavier weights backstage. No, no, no. I mean, we do have time. What?

We have time. Are you telling me... Now... This is just between us... and several hundred of you. I just want to say that this is 12.5 kilos, one arm. Oh my. Just rest it on there.

I think we need another strap. Take it off. Okay, so what we'll do, we'll feed that through there. Yes, you're right, this is podcast world. While you attach that, I'll read them the rest of Tim Peake's email. Oh, yeah, yeah. He says, dear Beck, big fan. Love all your stuff. It's been a real pleasure to help answer this question. And I hope you and whoever the other guy is have a great time at Blue Dot.

No, actually, he did share this story, which was the worst night's sleep that he had on the ISS, because obviously these LED lights, they're doing these experiments to see whether they do actually help with sleep. They can change the mood of the LED lighting. They can get rid of the blue light if they're trying to get ready to go to sleep. They can make them brighter

if it's meant to be during the day. But he said the worst night's sleep that he had on the ISS was when he was photographing the Bahamas at 10 p.m. space station time, but it was a sunny afternoon, Bahamas time, and he had a full five minutes of bright sunshine with lots of UV light hitting his retina as he was taking the photos. He said, I then went to my crew quarter, I couldn't

sleep all night. Top tip for space flight, don't look at the sun when it's close to bedtime Wow hashtag off-world problems mediums I don't know what I don't know what the weakest point is now other than me. I think the brooms will take it. Okay, do you want to get ready for the countdown? I'm gonna put it on here. We're gonna twang it and then you all yell ding and applaud. Okay here we go. Oh my goodness. Okay, here we go. Oh my goodness. It's got to say 22 and a half. It's just settling in.

Lift with your knees. It's just gently unscrewing the head of the broom. Oh my goodness. Okay. Can you hold this for one second, Bec? That sounds like a trick. Can you just be a counter-mass for one moment? Got it? Wait. Yep.

Wait. Let's put these on. Safety first, eh? All right. Okay. It's in the risk assessment. Okay. All right. Oh, really? Oh, that's good.

That's okay. Okay. Okay, I got it. I got it. You got it? Oh, my God. I'm going to go back on these fancy... These are the ones recording the actual podcast, so they're going to miss all the good stuff.

All right. You ready, Matt? Five, four, three, two, one. Liftoff! Did you sprint over there? Did you blackmail... You're like, now, listen, Legal Guardian, I learned a lot of new words tonight. And I can keep that between you and me

if I get to run over there and spoil this through. No noticeable difference. Do you know what? At first I was like, I didn't go that much further, but actually you are on a diagonal now. Yeah, yeah. So sorry people about there. We went all hypotenuse.

Yeah. But I do want to say, you've been here since we were sound checking earlier, so I like that. You've waited it out. Literally. That is the pun that keeps on giving. Oh, my goodness. He's off to kill some vampires or something.

Looking very Van Helsing over there. And that's how you launch a T-shirt into space. And so I think we can all give that a very big... Ding! Nice one, that. Good work, good work. All right. Well. We got any other business?

Any other business? Then we do any other business and notes and amendments at the end of the episode. I think that's a bit... So where's the book? Did we just establish where the book outlet is? Yes, Blackwell's Bookshop in Starfields tomorrow midday. So if you go there, I will be signing copies of Beck's books,

Horror Heights. Yep, which are horror books for anyone. I mean anyone, really. I was aged eight up, but, you know, I'm not going to do it younger than that. I'm not going to stop you from spending money on my things. And I will be signing copies of Matt's book, Humble Pie, which is very good.

I read that book and then I went, do you know what, I will do a podcast with you. Oh, that's true. That is literally the order it happened in. You've been bugging me for years. Yeah, there you go. So we'll be there at 12 o'clock tomorrow. We can do a t-shirt trade if you want to come along.

Oh, we will be selling the t-shirts as well. We do have a shop. Oh yeah. tmail.com forward slash a dash problem dash squared because I set it up while on the train. Dot email dot com. But there are official Problem Squared T-shirts on there.

So to finish it all up, we just want to say massive thanks to, obviously, our producer, Lauren Armstrong Carter, who's somewhere off to the side of the stage. And to everyone at Blue Dot, I'm thanking Sarah Bonetto, who booked us, and to Tim Peake. Oh, yeah.

Thank you very much for having us. Bye! This is our first time at Blue Dot as well. Yeah. I quite enjoyed the real reality arcade. They've got a bunch of arcade machines. My favourite is the whack-a-mole game where you get your children to pop their heads up and the parents get to whack them.

I think that's great. But they got Pac-Man, they got Donkey Kong. I can't believe they paid for all those different trademarks. Just incredible.